1/8 Porsche 956

Hello again!

It's not really a surprise, but this new project of mine will be a 1/8 scale scratch-built Porsche 956. This was Porsche's first design for the new-for-1982 Group C sportscar rules and it would enjoy a lengthy (and successful) career as both a factory racer, and a customer car.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956016_zpshhisl3ld.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956016_zpshhisl3ld.jpg.html)

This is the Minichamps 1/18 version of the 1982 Le Mans-spec car...and for comparison with the Moby Dick:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956017_zpswsot8tu0.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956017_zpswsot8tu0.jpg.html)

What am I letting myself in for?!

So, why a 956 and not the later 962? The main reason is that from various books I have several useful chassis and layout drawings, all of them 956-spec. I know that one of the main factors in the 935 'Moby Dick' taking so long was the lack of proper reference drawings – and it's not an experience I want to repeat! A second factor is that the earlier 956 is very closely related, engine-wise, to the 935-78. It has water-cooled heads, but still the traditional air-cooling for the cylinders and block. I'll be able to use most of my photos and references from the 935 to make the new engine for the 956.


A big challenge will be the creation of the aluminium tub chassis – not the usual 908 or 917-style tube-frame. Fortunately I have plenty of photos for this, both from books and from online searches, and the drawings. Of course, there will be plenty of other problems along the way – headlight covers and door hinges, for example – but I'll deal with those as they happen!


What's interesting (to me, anyway) with the 956 is that it was clearly a fresh start for the Porsche racing department, and you can see that in the design of many of the components. Throughout the 70's there was an obvious connection with all of the racing prototypes, from the 908 to 917, to the original 936, then the various updates running through to the last 936 in 1981. The frames are similar, the brakes and uprights are similar, the gearboxes are similar, etc. Although the 956 borrowed the 917's windscreen (sort of), everything else is fresh, and seems more 'refined' than the 70's cars. I suspect this will cause me a lot of headaches as I try to balance strength and durability of the parts, with the more detailed nature of the design.


Unlike my other projects, I am starting this one without a specific chassis identity in mind. The 956 was available with both 'long tail' bodywork for Le Mans, and 'short tail' bodywork for normal circuits – I prefer the look of the 'short tail' despite my love of Le Mans! Maybe I make both types of bodywork? I could go for a factory livery, or one of the privateer teams...lots of choices. At this early stage it's not too important – I won't have to commit to these details for a long time yet.


I started the build at the very end of 2018, during the Christmas holidays. After completing the 935 in mid-November I was ready to move onto something new! My first job was to create a scale drawing of the chassis tub, and to use that to make a cardboard mock-up. I wanted to get a feel for the size and shape of the tub, and how it differed to the tube-frames I was familiar with. Later, I could use the dummy tub to work out how I could mount the engine and gearbox – what's possible in real-life doesn't always translate to model-form, even at 1:8 scale.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956001_zpsqkrjlbmh.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956001_zpsqkrjlbmh.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956002_zpsmuaj1wuq.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956002_zpsmuaj1wuq.jpg.html)

The tub as you see it here only took a few days to put together. It's mainly thin cereal-packet cardboard, with some styrene box-section added in places for strength and alignment. The curved floor section in the footwell adds a bit of complication, but the overall shape is relatively simple. At this stage I haven't added all the little brackets and suspension pick-ups – these are all details that I will work out on the proper tub.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956003_zpsrqij2spu.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956003_zpsrqij2spu.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956005_zpsbvyaeqdo.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956005_zpsbvyaeqdo.jpg.html)

Having made the mock-up, the next question was: how to make the actual tub? It's supposed to be made from folded aluminium, so a smooth finish is necessary – I'll have to spray it eventually. Styrene sheet on its own will probably not be strong enough, and could lead to problems with distortion or glue-related pitting over time. I could make a tube frame and add outer panels, but would it be strong enough? My current thinking is that I should make foam cores for the main side-boxes, then add fibreglass, then a thin styrene skin. Hmm...how about a thin aluminium skin?


Either way, the weather for the first two or three months of the year would not allow me to spend much time working with fibreglass, or making a mess with foam out in the workshop. Until things warmed up a bit and the evenings start to get lighter, I would do something else to advance the project.


To work out how to mount the engine and gearbox properly, I would need an engine (or at least the block), so that's what I've been doing since early January. Construction is basically the same as for the 935, so I won't go into lots of detail at this stage – there'll be lots of things later which are specific to the 956. I've tweaked one or two little things here and there – partly to find improvements over the 935, and also to keep things interesting!

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956006_zpsbt69tp6s.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956006_zpsbt69tp6s.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956009_zpslvrd42yd.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956009_zpslvrd42yd.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956008_zps6zeforip.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956008_zps6zeforip.jpg.html)

So if I'm building one engine, I might as well build a second at the same time, right? Might come in useful sometime in the future, and it hasn't really taken much longer – I've been leap-frogging between them: while the glue's drying on one, I'm working on the other. I've concentrated on getting the two blocks detailed before moving on to the heads, cylinders, etc.


On the 956 there's a large fabricated mounting which bolts to the front of the engine and tilts the entire powertrain upwards by a few degrees. The first step with this was to connect four 1/8” tubes with lengths of box-section to make a simple U-shaped spacer – this would be the core of the front mounting:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956012_zpsjtkzriku.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956012_zpsjtkzriku.jpg.html)


The rear of the engine is supported by two large A-frames which bolt to the back of the main chassis tub at the bottom, and to the roll-hoop structure on top. Between the engine and main gearbox is a spacer module which includes two large arms – these arms spigot onto the A-frames and tie the structure together. The next step was to make a dummy spacer module from box-section and 0.75mm plate, and use this to set the engine at the correct angle:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956010_zpsfbddpb3a.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956010_zpsfbddpb3a.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956011_zpssl4frald.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956011_zpssl4frald.jpg.html)

At the top I've used two short pieces of 4mm tube to represent the base of the roll-hoop structure. For now the lower ends simply rest inside the brackets, but on the proper tub I have various options for running the tubes into sockets hidden inside – this should allow some adjustment, but also create a stronger connection than simply pinning them through. Being able to assemble and dis-assemble the drivetrain is an absolute requirement, but it helps if everything goes back into the correct position each time!


So, at this point I now have 75% of the drivetrain dummied-up on the back of the tub; even like this the engine is quite stable. The A-frame construction will be modified for more strength – possibly by running aluminium or brass tube inside, as on the 935 – I'll pin the ends together, and can work out the final fixes onto the back of the tub. The two lower brackets, for example, will effectively be purely decorative as the structural connection will be inside the tub.


For the last week or two I've been working on the proper front mounting. I re-made the U-section around longer lengths of 1/8” tube – my plan here is to run these into sockets inside the tub for an even stronger mounting. The engine's fan drive-pulley will fit inside the arms of the U. An angled 0.75mm plate across the front creates the basic shape of the mounting where it will attach to the back of the tub. Smaller lengths of tube at each corner can be used to pin the mounting in place (although this might not be necessary with the longer 1/8” tubes available), and these are reinforced with pieces of thick strip styrene:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956013_zpsonsqnra1.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956013_zpsonsqnra1.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956014_zpsapss58bx.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956014_zpsapss58bx.jpg.html)


Two 0.75mm plates close-off the back of the mounting, and I've added two sections of 11mm tube to create the swaged holes present on the original 956 part. The front plate has no holes (for strength, and they're not going to be seen). At some point I'll add some weld detailing around all the edges with Greenstuff and then it's ready for paint:


What's next? However I make the proper tub I'll have to mould the floor in fibreglass, so I guess I need to start thinking about shaping some foam to make the pattern. Assuming the weather doesn't revert to winter-conditions in the next couple of weeks I could think about laying-up some fibreglass soon. I'll need to make some more flat-sheet for use on the project too, but that's easy enough. I'm still undecided about the tub construction...If I can convince myself that an internal tube-frame will be strong enough, that could be the answer, but the shaped floor will certainly add to the challenge! Hmm...needs more thought.

Sorry if this first post has been a bit wordy - I knew it was going to have to be a long one, so actually started writing it a couple of weeks ago, and only copied-and-pasted it together with the photos today! Normal service will be resumed soon once I get the proper tub underway. I wanted to satisfy myself that the basic layout was sound before committing to a new thread...and here it is.

If I can get this one built in less time than the 935, I'll be very happy...!

SB

This is going to be fun, can't wait to follow this build!

Following!

another awesome build!

Oh yeah, can't wait to watch this one unfold! This is going to be epic! Second engine? Why not for the Dauer 962.

Mike

great project!So do you choose for the very first version of the 956?
in the engine compartment it had some differences compared to the following versions ('83, '84 ...), but I imagine you already know …

Great start!:thumbsup::thumbsup::thumbsup:

Buckle up, AF.

Another master class is about to start, and boy are we in for a treat.
Considering you just "happen" to build two engines at the same time, can I hazard a guess and ask if, per chance, we are going to see different versions? Or is it a preparation for the model after this one? :P

Great start. I love how you go about the process of reverse-engineering a real car and then recreate it in almost household materials. I've been stumped 2 times already with the projects I've seen here come alive (908, 935) and now I'm in for number 3 (I was too late for the 917).
As for the chassis. I would think about thin sheets of aluminium. But that is just my personal preference, because I like to have things made from their original material instead of painting something so it looks like what it really isn't. Plus I suck at painting. And at these size metallizer paints (or whatever you call them) like the xtreme metal paints from AK or Alclad etc. are going to be a pricey proposition. That aside, the metal would be a good for structural integrity and stability - but of course with the downside of adding quite a bit of weight that the suspension needs to be able to carry.

Hm food for thought, but hey, I'm glad you have to do the thinking and I can just sit back and enjoy the ride :D.

Did I say brilliant work so far? Consider it said :P

Hello folks,

The tub is certainly giving me some mental exercise as I try to decide on a plan! The cardboard mock-up is surprisingly sturdy, despite being put together relatively quickly, and as I don't have to worry about fitting a fuel tank into the rear bulkhead section I've got a relatively free hand in how I construct this area. The various holes and openings in the tub are going to be the things causing problems - I'll need to run pipes and cables into some of them, for example, so if I go down the foam-core route I'll have to start putting holes in it anyway. A concealed tube structure is appealing, but most of the tub is quite thin in cross-section (and will be even thinner once I allow for whatever outer skin is used).

I'll have to so some digging around in the scrap aluminium bin at work and see what I can salvage! Most of what we use is going to be fairly thick compared to a 1/8 model (eg 16swg) but there might be some thinner 18swg or 20swg offcuts I can experiment with. Although using proper ali has the obvious advantages in terms of colour and texture, I can see problems with detailing it (gluing, discolouration, scratches), and if it's thin enough to use on the model it might not be as rigid as I would like.

Yes, the engine installation does change over the years, so the current plan is 1982-spec with the Kugelfischer mechanical injection. I believe that this arrangement continued in use with some of the privateer cars during '83-'85, so I'm not just limited to using an original 1982 livery. Either way, I can make a final decision about this further down the line. It might just come down to what decal sets I can find to supersize...but I suspect the 956 is well-served in this respect. I have a few 1/24 956 and 962 kits in my stash already, so that's a start...

The second block just seemed like a good idea - even if it doesn't end up going into a car, I could finish it up as a display piece. It does mean that I don't have to keep removing and re-fitting the primary engine every time I want to check something, so I'm sure it will be of use as I make progress. Having all the photos on file from the 935 build certainly made life easier, and there wasn't that feeling of 'will it or won't it work?' from the first time. Of course, I will still have to build a new gearbox and the adaptor section, so I still have fresh challenges there!

SB

A good choice of an interesting car which will present some new challenges for your fabrication skills. I'm surprised that a box section of thickish styrene wouldn't be strong enough for the tub? I guess I don't really have an idea what one of these monsters weighs.

Looking forward to your (always entertaining) build reports. Hope you stick with the Rothman's livery!

ianc

awesome start, looking forward to this journey.


Paul

Hello again,

Right - change of plans! Before throwing myself into tackling the tub I felt it was necessary to spend a bit more time working on my 1/8 scale layout drawing, to get a better feel for the size of this thing. I've decided to put the tub on hold for a little while: I need to make the outer tub sections (sidepods) quite structural to support the weight of the main bodywork, and as these will be permanently fixed in place, I might as well incorporate them somehow into the main core monocoque.

The other issue is that the rear undertail and venturi tunnel bodywork section continues underneath the sidepods - it doesn't stop at the front edge of the engine bay. There's no point in making the tub and sidepods before I have the drivetrain in place to determine the shape of the undertail. It will all make sense in time!

So, new plan: make the adaptor casting which supports the engine and gearbox. I managed to find some more good photos of this online to add to what I already had - but struggling for a good clear view of the underside. I spent several nights drawing the basic shapes to scale and working out a plan, before starting to cut plastic. First stage was to make a series of plates and rings to create the front section around the engine's flywheel:

https://oi604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956018_zpszzwsvdbp.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956018_zpszzwsvdbp.jpg.html)

https://oi604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956019_zpswveh3tdx.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956019_zpswveh3tdx.jpg.html)

https://oi604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956020_zpstp5zt6ti.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956020_zpstp5zt6ti.jpg.html)

The rings were made by wrapping and gluing several layers of 0.75mm strip around a 'D' battery. The main body is 3/8" box section, with the ability to run a pin through from front to back, as shown. The notch at the back is where I will fit the crossbeam which will connect the two A-frames on the back of the tub.

Next stage was to start creating the rear end - a single plate to define the connection to the gearbox, then two more rings:

https://oi604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956021_zpssfnnbmfm.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956021_zpssfnnbmfm.jpg.html)

Finally for tonight, I've made a start on the underside. The four tubes on top will be the anchor points for the forward mounting for the lower wishbones, and these will be firmly supported by plates and pins. The plate on the bottom creates the split-line - the upper section of the adaptor has a removable cover which allows access to the clutch and release mechanism with the drivetrain still assembled. I can't fix this plate permanently until I've done more work on the crossbeam, but once it's in place I'll be able to start adding more detail to the sides.

https://oi604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956022_zps3oypuaqm.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956022_zps3oypuaqm.jpg.html)

So, work will continue - hopefully the next time you see it it will be looking more like the real thing. Once the adaptor is under control I can make a start on the actual gearbox, and then I can start thinking about the undertail…

Have a good week,

SB

Holy cow. Do you ever take a break? Haha

Excited for another great experience!

Wow.

gosh! this is amazing!!!!

Hello. Beautiful and thoughtful work. (My models would also look better if I spent so much time preparing.) I have one suggestion. Try to make the chassis from styrene coated with thin aluminum. I tried alu from a party tray. It's thin enough. The bonding of the parts is also solved because styrene is well bonded.
I will follow this project closely. It's great and informative.
"Tyrrell"
this is a translator, sorry for imperfection

I'm here again for learning!!

Thanks for everyone's comments and 'positive vibes'. You'll have to forgive my slow updates so far - it's one of those times where the progress seems to take a while to happen, despite lots of hours spent making large pieces of styrene into small pieces! As you'll see here, things are certainly moving along.

Having got the main body of the engine / gearbox adaptor under control, the next job was to tackle the beam (or 'ox-bow') which would connect the two A-frames. The core structure was put together from 1/4" x 1/8" box-section:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956023_zpsit0b8xh7.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956023_zpsit0b8xh7.jpg.html)

This would be combined with the top plate and more plates on the front to create a solid support for the back end of the car:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956024_zpspraze5ht.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956024_zpspraze5ht.jpg.html)

Of course, there were lots of other pieces required to make it all work - here's a selection before I started gluing it all together:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956026_zpsfsshdyb2.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956026_zpsfsshdyb2.jpg.html)

You can see that I filled in the ox-bow with various pieces of box-section for reinforcement. The two aluminium tubes are the main connections to the A-frames - these are slotted for the pieces of styrene strip to fit inside, which will plug into each end of the main cross-bar.

To increase the structural strength, I wanted to pin through into the sides of the module (rather than just relying on glued joints). You can see one of these pins below:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956027_zpskcv8h22y.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956027_zpskcv8h22y.jpg.html)

The circular boss is one of the two mounts for the top rocker of the suspension. There's more to add to this, but I wanted to create a solid socket to pin into later on. I used sections of angle to build up the shape of the rear part of the ox-bow, with the plan being to either fill in the gaps with greenstuff or styrene, before adding more plate-work to finish off.

As you can see here, I used more styrene to shape the back, and more on top:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956028_zpshahzvcd3.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956028_zpshahzvcd3.jpg.html)

There's a 0.5mm gap between the rear of the ox-bow and the plate which defines the back face of the adaptor. This will allow me to slot in a piece of 0.5mm styrene sheet each side.

Jumping forwards a bit, here's the adaptor in it's latest state:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956029_zpsycu15cao.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956029_zpsycu15cao.jpg.html)

I addition to the two 0.5mm plates on the back, I've wrapped two more pieces of styrene over the top and undersides of the ox-bow. The ali tubes have been fitted in place, and the styrene wrapped around them. This arrangement is a little different to the real car, but I've done it this way for extra strength - it might be modified later on.

At this stage, it's not really necessary to continue adding more detail to this piece. For what I need to do this summer, I just need to connect together the basics of the engine, gearbox and adaptor in a solid and repeatable way.

So, time to start on the gearbox itself. First job was to make a scale drawing based on measurements taken from the various official drawings, combined with info from the many photos. As with the 935, I'll make it in three sections - diff housing, gear cluster, and the end-cover - rather than trying to do it all together.

The starting point for the diff housing was the front plate where it connects to the back of the adaptor section. This includes six thick bosses where the bolts go through, so these were made from 4mm x 2mm strip, rounded at the ends. A 1mm disc was cut and inserted between the strip sections, with a further 0.25mm plate on the back to tie it all together:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956030_zpsuvmyss0t.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956030_zpsuvmyss0t.jpg.html)

The square plate will form the backbone of the diff housing, made from more 1mm styrene. The two sides of the housing are quite different, so I can build them up separately. One of the hardest pieces will be the cover plate on the RH side:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956031_zps7dqgkkwm.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956031_zps7dqgkkwm.jpg.html)

Lots of detail, lots of fins, webs, and all sorts of stuff that will take time to sort out! It doesn't help that I don't have a proper square-on view of this side of the gearbox, but I'll work with what I've got. The 935 was similar, so it's not my first attempt at this sort of part! I started with the disc of 0.5mm styrene in the photo above, then added two rings of 0.75mm to give it some depth:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956032_zpsphf02gox.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956032_zpsphf02gox.jpg.html)

The notches around the edge will need some work, and there will also be small bulges on the inside and strips running to the centre. It's a long way from being finished, but once I have the two side-plates they will play a big part in defining the overall shape of the diff housing.

Let's see what happens!

SB

Love it!

So cool!

Your scratch building capabilities are just unreal.



I can't wait to see your progress on this one.

Time for another update!

As it turned out, the cover plate for the RH side of the diff housing wasn't too bad. Having marked it all out and added the edges (as seen in the last post), everything else was basically just filling in the gaps. A short length of 11mm tube was glued in the centre, and then it was the time-consuming job of cutting and shaping the 24 fins. After that, very short pieces of strip were added between the fins to create the middle ring:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956033_zpsniyvphxf.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956033_zpsniyvphxf.jpg.html)

Next, I could start building the diff case itself. Four strips of 0.4mm styrene were layered together around a useful offcut of nylon rod to create the central 'drum' section. Assorted discs of styrene were cut and used to locate the drum onto the backing plate, and the cover plate:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956034_zps3p5havkm.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956034_zps3p5havkm.jpg.html)

In this photo you can also see the early stages of the bellhousing section which will attach the gearbox to the back of the spacer / ox-bow. The main positions of the mounting bolts have been fixed by the three sections of strip with the rounded ends, but there will be more work later to make the transition to the diff-housing.

Here's a shot of the main components at an early stage before I started gluing things together:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956035_zpsn4wdgets.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956035_zpsn4wdgets.jpg.html)

From the left we have the LH side of the diff-housing. The detailing for this is quite different to the other side, as you'll soon see. Next we have two small panels, made from various pieces of strip, which are the starting point for the flange between the diff-housing and the gear-cluster section. Then it's the RH side of the diff-housing, and the front plate.

Fast-forward a bit and you can see how things have developed:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956039_zpsgou4tnls.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956039_zpsgou4tnls.jpg.html)

This side of the front plate has had more sections of strip added which will define the positions of assorted 0.75mm webs - these will run across the side of the diff housing and meet-up with more from the top, bottom and rear. The centre piece has been bulked-up with lengths of 0.5mm strip to create an internal chamfer; my original plan was to then fill this with greenstuff and smooth it out, but when I started cutting the slots for the webs the greenstuff didn't key properly and pulled out! For now it's had some work with emery cloth, and will be fettled more before it's complete.

These shots give you an idea of how the webs will slot into place:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956036_zpsrwns0lwo.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956036_zpsrwns0lwo.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956037_zpselcbebrw.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956037_zpselcbebrw.jpg.html)

By the time of the second photo I've started adding more strips to control the webs across the top of the gearbox too. The curved section in the middle of the photo was built up from five layers of 1mm sheet, then lots of sanding to add the chamfer. Once the basic web positions were fixed, I could cut this piece into sections to fit in between.

The two sides of the diff housing have been glued together, and the front plate has been added too. Here you can see how the central spine now has extra strip on both sides for the webs:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956038_zpswnjvshje.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956038_zpswnjvshje.jpg.html)

So, still a lot to do. It feels like it's been slow progress, but there's a lot of effort in these parts, and a lot of trimming, fettling, positioning, thinking and finally gluing! Now that this core section is glued it should help as I'm not having to hold it all together whilst I work out what to do next - things stay in place. I've rough-cut a lot of the webs already, so when I'm ready it will start looking quite different quite quickly. The underside needs more work where the wishbones will attach, the rear needs work where it meets the gear-cluster...and the top needs work too.

Getting there, though!

Have a good week.

SB

Simon, your scratchbulding skills are out of this world, but to me, its your vision on how to approach certain things that makes your model building so unique and SO good.
Terrific update once again my friend, and please keep on building!
Patiently awaiting next installment!

Hello again,

Sorry it's been a while since the last update - the back end of the gearbox has taken me longer than I planned to get to this stage, so I've been waiting until I had something useful to show before posting.

Adding the web-plates to the diff-housing was certainly much easier having first put the pieces of thin strip in place to locate them:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956040_zpsbry1vqdl.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956040_zpsbry1vqdl.jpg.html)

At the front I added shaped pieces of styrene to create the curved transition between the back of the adaptor and the gearbox. Again, much easier to do with the webs firmly held in place...but still removable if necessary:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956041_zps7mipq2zi.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956041_zps7mipq2zi.jpg.html)

The transition piece on the other side was smaller, due to the size of the diff cover plate. This started life as several pieces of rough-cut styrene glued together, and then filed and fettled to shape:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956042_zpsd4sydyy0.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956042_zpsd4sydyy0.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956043_zpskhchusoh.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956043_zpskhchusoh.jpg.html)

At this point I realise that I haven't taken any photos of the diff-housing in it's 'finished-so-far' state. No problem - there'll be a few of these next time as I have to return to it to continue the mounting flange onto the gear-case.

The gear-case itself is what's been occupying most of my time since returning from Le Mans. I knew it would be constructed in a similar way to the 935 - split into sections either side of a centre-plate, with the webs added in between - but I wasn't totally sure of the shape. The two halves are not symmetrical - the selector mechanism is on the left-hand side - so I had to make eight different sections, each comprising a top half and a tapering lower half.

Having drawn-up the basic layout, I started putting the sections together from various sizes of box and strip, with an outer skin of 0.4mm strip added at the end:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956044_zpsy0icbhaf.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956044_zpsy0icbhaf.jpg.html)

The web-plates have been rough-cut from 0.75mm sheet and their shape will be refined as the gearbox is assembled. The upper and lower pieces all sandwich a further piece of 0.75mm strip, creating another web down the length of the case:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956045_zpsglkentka.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956045_zpsglkentka.jpg.html)

As with the diff-housing, I made the centre plate from two 0.5mm plates, allowing me to glue the two sets of sections separately. The web-plates are not glued at this stage, but are in place to make sure everything is correctly positioned during the gluing process:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956046_zpsokmnjdfd.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956046_zpsokmnjdfd.jpg.html)

After this I could start trimming the backing plates to shape, and eventually glue the two halves together. I cut a small slot inside each of the plates to create a 1mm hole on the centre-line, allowing me to pin the gearbox together. It still needs more work, but it's looking better:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956047_zpsds7zglgm.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956047_zpsds7zglgm.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956048_zpsqsu3m8pt.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956048_zpsqsu3m8pt.jpg.html)

It's only when all four sections are fitted together that you appreciate the size of the 956 powertrain - and I still have to add the gearbox end cover:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956049_zpswpku9pku.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956049_zpswpku9pku.jpg.html)

So, what's the plan from here? First, I need to spend some more time working on the mounting flange detailing between the two sections of the gearbox. There's still plenty more other detail to add, but that can happen later - I can do a lot of this during the winter months.

I really want to spend some time shaping the underwing and floor in fibreglass before the end of the summer, so I can make use of the better conditions. To do this I need the basics of the powertrain in place, together with the cardboard chassis tub, etc. My original plan was to have these basics in place by Le Mans, but that deadline has now slipped slightly!

I reckon another week or so should put me where I want to be, then it'll be time for more drawing, blue foam, cardboard and hot-wire cutting. I'm still undecided on the chassis construction, but I'm hoping that having the floor available (even if I have to mould a Mk2 version later) will help to make the decision. If I can get some good progress with the fibreglass before the end of September, that should be enough to keep me busy into 2020!

All the best,

SB

Excellent update once again!

Hello again,

Time for another update - to be honest, I hadn't realised that it had been so long since the last one. Quite a lot to report, though, as I've been busy - although not necessarily with the jobs I thought I would be doing!

So, early last month I was considering making some moulds for the undertray / floor panel. I spent a couple of afternoons playing around with some cardboard to make some mock-ups for the ground-effect tunnels, but I just wasn't happy that it was the right time to continue with this work. I still wanted to get some fibreglass parts underway, so I made some simple foam and cardboard moulds for the main tub floor and the inner and outer tub skins:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956050_zpsttvl9zuj.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956050_zpsttvl9zuj.jpg.html)

This is the floor and outer tub skin. The pencil lines are marked onto the moulds, not the panel - although when the panels were removed I was pleasantly surprised to see that the indentation has transferred to the fibreglass. It'll make things a bit easier when I start trimming. Here's the two side panels:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956051_zpssfcencmt.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956051_zpssfcencmt.jpg.html)

...and the floor:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956052_zpsmccwydtp.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956052_zpsmccwydtp.jpg.html)

Other than a wash to remove the greasiness of the release-agent and a quick trim around the edges I've not done any extra work on these. Each panel is a combination of five layers of different cloth weights, for a thickness of about 0.7mm. They'll lose a bit when they're sanded smooth, but as they won't be the outer layer I can adjust the total thickness when I add the styrene final skin.

Next up, a bit more gearbox detailing. Although there is still plenty of work to do here, I particularly wanted to sort out the area where the lower wishbones will attach. My photo references for this area weren't great, but what I've done is very much in keeping with the original design, and should provide a strong foundation for the wishbone bracket. It'll all be hidden when the undertray is fitted, but we all like to know the detail is there, right?

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956053_zpsbosc9frh.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956053_zpsbosc9frh.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956054_zpso3dxtwji.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956054_zpso3dxtwji.jpg.html)

The main work for the last couple of weeks has been on the inner tube-frame for the tub. The cardboard version has been very useful as a reference - I didn't work out the frame design in advance, I just started making a structure that would fit inside the pattern. First step was a U-shaped base layer in 8mm x 5mm box:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956055_zps7uosnw0j.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956055_zps7uosnw0j.jpg.html)

This sets the internal width and defines the flat section of the tub where the driver will sit. Most of the rest of the structure you see here is made from 1/4" x 1/8" box, with lots of internal pinning for strength and location:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956056_zpssxzn1pii.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956056_zpssxzn1pii.jpg.html)

The section at the far left made from three pieces of box is where the front of the tub will slope upwards, and will eventually tie in with the rearmost mountings for the front wishbones. The rear of the tub below the fuel tank also slopes upwards, but this is where I will be incorporating the engine mounting.

It's only in the last couple of days that a lot of this has actually been glued together, so for most of the time it's been possible to take everything apart. The priority with the engine mounting has been to create a firm, strong structure - the positioning of the main beams has been defined by the external shape of the tub, so I've had to work the mounting tubes into them with a bit of filing and fettling:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956057_zpsvtlfkjyt.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956057_zpsvtlfkjyt.jpg.html)

After that it was a question of adding more tubes for reinforcement - both for the engine mounting, and to strengthen the overall frame:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956058_zpsfkrwg3ey.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956058_zpsfkrwg3ey.jpg.html)

Here's the frame as of this evening:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956059_zps6cbcjhcz.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956059_zps6cbcjhcz.jpg.html)

I've added 1/8" diagonals into the side frames, and you can see how the engine mounting plate slides into the four tubes that are now part of the chassis. The next challenge will be to create strong pick-ups for the two engine side A-frames, extend the rear part of the frame upwards and forwards to create the full fuel-tank section, and to taper the front towards the pedal-box. I can see that I'll be busy with this for some time to come, but with a holiday next week I should be able to make some good progress before the next update.

Have a good week,

SB

Nice. Where do you get your info as far as the design of these elements? I assume there are books and blueprints online, was just wondering, as you reproduction seems very exact.

Hello 360spider,

There's various drawings of the chassis, suspension, etc, in assorted books I've collected over the years, but everything I have is for the 956 rather than the 962. As with the Moby Dick there's a lot of useful photos on the Freisinger Motorsport site, and some good stuff on the Pelican Parts forum, so I'm pulling lots of info from those sources. There's enough info on the gearbox and spacer module on one or two of these drawings to get the basis dimensions 'about right', but the rest comes from searching the books and online images. The engine will be very similar to the 935-78, so that's less of a worry - I've got lots of photos of what I made last time!

The problem, of course, is working out the little details that are 956 or 962-specific, or the cars that are genuine Porsche tubs compared to the ones made by other workshops, or simply the fact that over the years many things get altered! That's why for now I'm not basing this project on one particular car - there's not really enough reference material on any single chassis. It'll probably end up with details from several cars, and the livery will depend on what I can paint, and what I can make decals for! Fortunately I have a few un-built 1:24 956 and 962's in the collection, so they might be donating their decal sheets to the project, as per the Moby Dick...

The tube-frame is my design, working to fit the measurements of the original aluminium tub. It probably won't be as elegant as the genuine frames for the likes of the 908 or 917, but as it won't be on show I'm looking for strength and stability, rather than a 'perfect' frame. It also means I don't have to add all the weld details! Given how sturdy my original cardboard pattern tub is, I'm hopeful that the styrene-and-fibreglass version will be up to the job. These 1/8 cars get quite heavy, though, when you start adding the transmission, bodywork, etc.

SB

I see. Well, you are doing heck of a job. Keep at it, I am following this build closely.

As usual SB - unF*ing believable work

What you can do with simple styrene is very impressive.

I'm on board for this build.

Cheers
John

Thanks John - I think tonight's update will be to your liking: lots of large pieces of styrene cut into smaller pieces of styrene!

So, at the beginning of August the chassis frame was underway but very much in the early stages. It has taken pretty much the whole month to get the main cockpit section relatively complete. Although the cardboard mock-up gives me a basic pattern to work to, it's been surprising how much I've had to put into this thing in order to be happy that it will be strong and accurate.

To start with, I worked on filling in the lower section of the back panel, either side of the engine mounting:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956060_zpsji9h3y81.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956060_zpsji9h3y81.jpg.html)

The two large pieces of box-section in the lower corners will give me solid fixing points for the engine support A-frames later. I put the 1/8" diagonals across the openings before remembering that I wanted to allow for dummy openings for the fuel tank plumbing and some of the water pipework. The larger round hoop was made from a few layers of 0.4mm styrene wrapped around a length of tube as a former - I then cut out the diagonal tube to suit and fitted everything into the gap. A piece of 0.75mm sheet glued in from the other side ties it all together.

From the front, I continued adding more diagonals and braces. The piece of fibreglass laid into the floor defines the front edge of the main rear firewall / bulkhead, and you can see in the corners where I've started adding some box and sheet to 'control' the bulkhead position:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956061_zps6tdxzran.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956061_zps6tdxzran.jpg.html)

The rear firewall was made as two panels, leaving a 2mm gap between them - this will allow me to add the central cockpit 'spine' later:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956062_zpsgmke9gls.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956062_zpsgmke9gls.jpg.html)

You can see here that I've also started building up the rear of the tub. Although the top of the engine A-frames fix to the roll-over hoop, the roll-hoop also needs a secure fixing to the tub. Two lengths of large box-section are securely anchored into the bottom of the tub and give me the main vertical supports - they also give me a solid base for the firewall panels.

The upper section has been reinforced with more diagonals for the firewall frames, and a mix of fibreglass and styrene panelling:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956063_zpsbndiebmg.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956063_zpsbndiebmg.jpg.html)

The upper fixings for the A-frames are two lengths of 4mm ali tube which have been pinned and secured into the rear frame - you can see one at the far left of the above photo. It would have been nice to have them slightly further forward as it would have given me more options for how I incorporated them into the frame, but they are where they have to be! The round hoop at the left is where the gearshift will pass through the fuel tank area - there'll eventually be a similar hoop in the front of the panel, with a length of tube connecting them.

The firewall frames are a mix of 1/4" x 1/8" and 1/8" square box-section, with sheet reinforcement on the back, and pinned together in various places:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956064_zpsjfsqcmor.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956064_zpsjfsqcmor.jpg.html)

Here's a better view of one of the ali tubes. The upper section has been panelled with fibreglass sheet and styrene diagonals, and I've added the two outer sill sections along the sides of the cockpit:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956065_zpsl9tkn2yn.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956065_zpsl9tkn2yn.jpg.html)

Moving to the front of the tub, I started the footwell section by cutting two panels in fibreglass and styrene and using these as a baseplate, pinned to the substantial crossbeam which sits below the driver's legs:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956066_zpshtcv6owf.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956066_zpshtcv6owf.jpg.html)

The inner sides are made from yet more 1/4" x 1/8" box, and will eventually be pinned into the main tube, as well as the connections to the crossbeam below. The baseplate has been cut to give me the shape for the pick-ups of the lower wishbones, and will allow me to build down to meet the floor panel.

The outer sides were made in a similar style, with some shaping and filing around the front end to allow them to fit together with the inners at the correct angle. More box section has been used to lock the two sides together:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956067_zpsrpvsqmii.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956067_zpsrpvsqmii.jpg.html)

The fibreglass panel at the left of the photo is the starting point for the front bulkhead - this will eventually be reinforced with two styrene panels, and have cut-outs for the master cylinders, etc. I cut a slot into the inner cockpit sides to fix the position, and will soon cut away more of the baseplate in this area to get the final shape - I've left it oversize for now. The front bulkhead has to extend below the level of the baseplate eventually.

In this final photo you can see the comparison with the original cardboard version again. I've made a start on the dashboard hoop, and will continue working on this area this week. At some point I'll glue the footwell onto the cockpit section, but the upper has to stay removable to allow access for fitting pedals, wiring, steering rack, etc. I'll have to get in there to paint it, too!

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956068_zps32qnf3c9.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956068_zps32qnf3c9.jpg.html)

It's coming along well, but there's still lots to be done - and that's before I start on the outer skins in fibreglass and styrene (plus rivet detailing...). I reckon I'll still be working on the dashboard and upper section for the next few weeks, certainly. I'll have to lay-up more flat fibreglass before I can start the panelling, so that's something I'll also try to do this month while the weather is relatively mild. I'm hoping that by the end of the year I'll have something that looks more like an ali tub than a tube frame, plus the core of a drivetrain that I can hang off the back of it - I think that'll be a pretty good start to the project!

Thanks for looking.

SB

Awesome styrene work my friend.

It's amazing how much more refined your work has become since those first couple of Porche's you built.
It's amazing watching you hone your skills over time.

Thanks, ferrariman81 - you're right: there's a lot on my first 917 and 917-10 that I would do differently now, but that's the benefit of another fifteen years modelling experience and a lot more books than I had back then! if I can find new or better ways of making the parts as each project develops, that's great - it keeps things fresh for me, and hopefully stops each thread becoming 'more of the same'. The little styrene nut and rivet details from Japan have been very useful too, though! Maybe when the 956 is finished I'll go back to the 917-10 and give it a restoration? The bodywork and livery could certainly be improved (full Brumos colours?), maybe a new steering wheel (as per the 935 build), and perhaps some new wheels and tyres...?

That's for another time; meanwhile, the 956 continues. Before I permanently fitted the two sections of the tub together, I spent some time rough-trimming the inner fibreglass cockpit panels:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956069_zps8rrnxz8i.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956069_zps8rrnxz8i.jpg.html)

You can also see in this photo where I've fitted mounting tubes for the main dashboard frame (by the red clips). Annoyingly these are right in the way of where I would have loved to put some extra reinforcement between the two sections of the tub, but I was happy that I could get around this little problem. The next photo shows a detail of the joint, once it was all glued together:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956070_zpslgou15sp.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956070_zpslgou15sp.jpg.html)

The lower cross-member (where the floor will start to slope upwards under the driver's legs) is securely pinned and glued to the front of the main tub. A pair of lengths of 1/8" box run back from this into the insides of the tube and are glued to the inner fibreglass panels, with extra styrene strip reinforcement. Citadel 'Greenstuff' has then been worked into the joint and around the dash frame supports to help key both sections together. For a final touch, the outer frames which make up the front of the tub also have some small extension pieces which run into the rear section, and these too are pinned after fitting. At this stage it all feels surprisingly solid, and that's before I've added the outer fibreglass skin...

Next, a small diversion to the rear of the tub - I wanted to create the angled section under the fuel-cell area, so used six lengths of 1/8" x 1/4" box with a bit of trimming and filing, then filled the gaps with 0.75mm sheet styrene:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956071_zpsolxhlz9m.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956071_zpsolxhlz9m.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956072_zpsn1tb41qp.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956072_zpsn1tb41qp.jpg.html)

Back at the front, I started building up (or actually, building down) the underside of the tub to meet the floor. The pick-ups for the lower wishbones are recessed into this area - I'm not finalising the holes until later when I make the wishbones, though.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956073_zps1ufhm34s.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956073_zps1ufhm34s.jpg.html)

The upper suspension pick-ups will sit on the top of the tub - here's the early stages:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956074_zpsxvmajwm4.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956074_zpsxvmajwm4.jpg.html)

The front leg pick-ups are pinned through into the tub, and are made from 3/8" x 1/4" box section. The long beam in the foreground is the main support for the front dampers - this is also pinned through to the tub, and in time will be detailed and extended down to the floor.

After a bit more work:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956077_zps9olox3ck.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956077_zps9olox3ck.jpg.html)

You can see how the damper beam is spaced up on two 2.5mm thick pads to get the correct height. The extra length of box-section with all the holes will close-off the damper beam to the underside of the tub outer top panel. The lower wishbone front pick-ups are now fitted in place (requiring two holes to be cut in the floor panel to fit over them), and you can also see where I've extended the very front of the tub.

Nearly there for tonight! Next, I've cut and glued the fibreglass plates across the top of the tub - more reinforcement! They stop just short of the damper beam, and I'll add some smaller plates across the tub to connect this to the front pick-ups.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956075_zps1go9zcmj.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956075_zps1go9zcmj.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956076_zpsrabwk7yj.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956076_zpsrabwk7yj.jpg.html)

That's it for tonight. I need to finalise the angle of the dashboard frame fairly soon, as I can then start working on the outer panelling for the front of the tub. The flat panel across the very front needs more detailing, holes for the master cylinders, etc, and there's a whole load of other things to do. I've started trimming the floor to shape, but I don't think this will actually be fitted for a while yet...maybe!

Have a good week,

SB

Every time I see your hand on one of these photos I'm reminded how huge that thing actually is!

I agree with 360spider -

I work mostly with 1/12 now and that looks small compared to 1/8 - lol

Really amazing work SB to see this build come together.

You are truly a master at these 1/8 builds from raw styrene.

Cheers
John

Hello again,

Yes, on the subject of size the tub itself is quite misleading - the finished car will be about the same overall size as the 935-78, and yet the tub is (currently) much smaller than the tube-frames from the older racers. What's interesting is that the width across the inside of the 956 tub is within about 1/2" (full scale) of the width across a S3 Caterham 7 chassis...and the 7 is not a big car!

So, the next job was to extend the basic dashboard hoop structure with some fibreglass panelling:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956078_zpsnwoy9oee.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956078_zpsnwoy9oee.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956079_zpsiekcsncc.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956079_zpsiekcsncc.jpg.html)

The joints were reinforced on the inside - the front anti-roll bar will eventually locate onto the front of these extensions, so they need to have a bit of strength.

In the next photo you can see where I've added top plates to the tub either side of the mounts for the damper cross-beam:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956080_zpswoxrp4rd.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956080_zpswoxrp4rd.jpg.html)

These will be trimmed back a little when the outer tub skins are added.

The damper cross-beam has been reinforced with some doubler plates, and a slight extension on the top which mates up with the tub top skin. The dashboard hoop has been given an outer skin of styrene, and a length of angle across the top edge which will locate the top of the tub:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956083_zpssppy6yxu.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956083_zpssppy6yxu.jpg.html)

I've made the inner and outer skins for the angled sides of the front of the tube, but these need to be refined a little. The top panel has several access holes cut into it, although some of these will be covered when the windscreen surround and dashboard are fitted:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956084_zps1jhxcwpo.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956084_zps1jhxcwpo.jpg.html)

It seems like I've been working on the front of the tub for weeks, so for a change I wanted to sort out the rear corners, either side of the fuel tank area. The outer skins here will be angled in two directions, so the supporting frame had to allow for this. Here's the left-hand side:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956081_zpsxqqpvs1r.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956081_zpsxqqpvs1r.jpg.html)

The right-hand side is a little different as it has to allow for the gearchange to pass through:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956082_zpszbafi19k.jpg (http://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956082_zpszbafi19k.jpg.html)

I've boxed-in the interior here as I didn't want anything to fall into the inside of the chassis! The greenstuff looks a bit rough, but it's all been flattened to the right shape for when the panels are fixed. There will eventually be a couple of outrigger frames to support the various rads and coolers which will mount to the tub in this area, so I might add some more internal plating to give me something solid to drill and pin into.

...and that's it for tonight. I've made a start on the detailing for the master cylinder mountings, so you'll probably see that next time when I've got it a bit further. Reference photos of the pedals themselves are a bit scarce, so they might end up borrowing details from some of the older cars - I'm still hoping I'll find the right photo, though. I'll continue rough-cutting the external panels in fibreglass and styrene, but I need to plan how I'm going to interlock everything.

All the best,

SB

Wow, completely masterful work in every aspect. Huge respect and I have been following your builds for a long time. You have a talent which should be shared with the greater public!!

A question I have is why styrene is your method of choice in structural parts like this? Is it the rapid pace of building that is the advantage? I have scratchbuilt stuff with styrene a fair amount, but when it comes down to strength and fidelity, especially with a riveted chassis, wouldn't working with metal have an advantage?

The reason why I ask is with so many suggestions of strength, is there a reason why you aren't considering working with metal sheet, soldering and machining?

Keep us posted scratch. Miss those big, beautiful updates

Sorry for the slow reply, Raikkobin - I've had a productive couple of weeks since my last update, but I should have said hello earlier! My continued choice of styrene for the main construction is a combination of several factors: availability, ease of working, 'knowing the material', and the fact that I do most of my modelling sat on the floor in my bedroom!

Although an aluminium or brass construction would be appropriate for the 956 tub, I'm not really equipped to cut, shape or join these materials easily. For me, that's crossing into the territory of 'model engineering' rather than 'model making'. I like the idea of building using relatively simple tools and readily-available material - not everyone wants to spend years building a single model, but there's not really anything I do that couldn't be done by anyone else.

I'm pleased with the strength and solidity of the styrene tub - and it should improve further once the outer skins are attached. Yes, it means that I'll have to make it look like aluminium later, but I think I'll be happy with that decision when I'm trying to glue on dozens of rivet-heads!

So, what's new tonight? First up, I've been making the pedals:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956085_zpskyu7bp5l.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956085_zpskyu7bp5l.jpg.html)

The fibreglass mounting brackets on the brake and clutch pedals will be attached to both the floor and the front bulkhead, whereas the throttle pedal simply attaches to the floor. I found some good reference photos on a 'Scale Motorsport' CD I bought a few years ago, plus my friend Rijk emailed a couple to me, so they're as accurate as I need them to be. I'll probably add some texture to the pedal pads when I paint them, and there'll be some more detailing on the brackets when they're fitted into the tub.

Following on from the pedals, I've made good progress with the three master cylinders and fluid reservoirs:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956086_zpsslzdem5z.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956086_zpsslzdem5z.jpg.html)

These are still in 'kit form' for now, but don't need much work to be finished. The main bodies of the cylinders are 1/8" tube, and the two larger reservoirs are 3/8" diameter. The caps are 2mm thick, with the ribbing added by gluing lots of short strips of 0.25mm styrene around the edge:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956087_zpskhu7bdxp.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956087_zpskhu7bdxp.jpg.html)

Again, there's a few details to be added - the connections for the pipework, fixing nuts, some greenstuff to fill in the gaps, etc - but the bulk of the work is done.

The next job was one pf those things that I thought might give me some trouble, but - so far - it has worked out okay: the steering rack. On the older cars like the 908 and 917 the steering rack is clamped to the chassis with two pairs of blocks, so the rack itself can be made as a mix of different-sized tubes. With the 956/962, the rack casing has the mountings cast into it - and as well as mounting the rack to the tub, it also locates the rear legs of the top wishbone. So, it's a little more 'structural' than I've made before!

So, I started by measuring the basic dimensions from my reference drawing, and making a simple cardboard pattern. I made a template for the Y-shape ends from thin sheet, then used this to make the proper ends in 0.75mm styrene, gluing them either side of a length of 3/16" tube:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956088_zpsbinim5gu.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956088_zpsbinim5gu.jpg.html)

The wishbone leg will fit into the double plates on the forward side, the rack bar will fit through the middle of the 'Y', and the rearward side of the lower plate will give the second attachment to the tub:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956089_zpscf1m3les.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956089_zpscf1m3les.jpg.html)

I filled the gaps around the Y-plates with greenstuff, then filed and shaped everything to give a smoother transition from the main tube to the outer ends. The pinion housing lines up with the slot in the dashboard where the steering column support will be, and I can adjust the height of the rack if necessary by shimming underneath. My first job tomorrow evening will be to make a dummy top wishbone and make sure everything will fit into place - I know I'll have to trim the openings in the outer skin panels slightly to clear the rack mounts, but I need to err on the side of strength!

I have a couple of weeks holiday coming up, so I'm planning some new jobs that I can really get stuck into - make the steering wheel, gearshift, maybe the fire extinguisher bottles, maybe the main roll-over cage structure too! I won't be doing any fibreglassing, but there's plenty of these detail jobs I can spend some time on.

All the best,

SB

Nice work, as usual...and is that a Vostok I see on your wrist, ya commie?

Very cool solution to make the ridges on the reservoir caps. Great work as usual my friend.

Re: 1/8 Porsche 956

Just loving this latest masterpiece SB. If I can presume to make a suggestion for your next museum piece; I've always admired the Group 5 era cars with their big box guards and "cow catcher" from ends, but favourite of all time was the BMW CSL Turbo Group 5....what a car especially in either the Gösser Beer or Jägermeister liverys....
Just a thought. Keep up the great work.

Cheers & Beers

Keep em coming SB. You're an absolute wellspring of knowledge.

Hello again,


It's been a productive couple of weeks since my last update – having some time off work is always good. As usual, I've been able to do plenty of jobs I wanted to do, some jobs I hadn't expected to do, and didn't do a few things I planned to! I've got about seventeen photos to go with this one, so I'll break it into two and post the second half tomorrow night.


So, what's first? With the steering rack drilled and pinned in place I made a couple of cardboard templates for the front upper and lower wishbones – I wanted to be sure that the suspension pickups were in basically the right place, and that the damper mounting wasn't about to get in the way:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956090_zps0clh7gph.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956090_zps0clh7gph.jpg.html)

Looks good so far. I've deliberately left the pick-ups undrilled for now until I start making the wishbones, so I've got a bit of wriggle-room for correcting the set-up geometry. The lower wishbones will be quite solid in construction, but the uppers are going to be a little 'fiddly' – I'll need to be careful how I make these.


Next, I made the centre spine which divides the cockpit. I've left slots in the rear bulkhead and the front crossmember, so there's no problem getting the alignment right, and hopefully it will stiffen the floor. I made it in three layers – 0.5 and 0.75mm styrene for the outer skins, and a fibreglass centre – which should help to avoid warping over time. You'll see in a later photo where the swaged holes have been cut out, and a slot added for the upper seat mounting; when it's finished it'll also have a lip added to the top edge.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956091_zpsalqkvswg.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956091_zpsalqkvswg.jpg.html)

I wanted to get the tubular roll-over hoops underway during my holiday too, as I knew these would be a time-consuming job. As well as making the actual hoops, I also had to start making the folded brackets which would attach them to the tub, and to make those I had to make sure the tub skin was layered-up properly.


Here's the rear hoop over the top of the fuel cell:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956092_zpshootfctn.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956092_zpshootfctn.jpg.html)

At this stage I had layered the inner fibreglass skins with the outer styrene skin, then made the top brackets to suit. The ali tubes at the rear corners will eventually connect to the main hoop, and provide a neat location for the brackets in the meantime. The hoop has been formed from two lengths of plastic-coated wire rod, with short sections of styrene tube threaded over the top – Greenstuff will fill the gaps, and there will be lots of filing and smoothing to get it all looking right!


The fuel cell top panels received more attention – there will be two large swaged holes in the top of the tub where the fuel filler and breather tubes will exit, and a third hole where other fittings attach to the bag tank. The black rings of till-roll tube will create the swaged edges, but I also cut through the fibreglass layer so that I could inset three styrene discs as the 'top' of the bag tank. If I'm lucky I can add the detailing to these discs but leave them 'floating' in the top of the tub – might make it easier to get everything lined-up when the bodywork is eventually fitted.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956093_zpsipvhob4d.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956093_zpsipvhob4d.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956096_zpsnitlffiw.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956096_zpsnitlffiw.jpg.html)


With the rear hoop under control, I spent some time working on the front hoop. For now I've dummied this up with length of (slightly oversize) flexible fire-extinguisher piping, but I need to make it properly as per the rear hoop. The mounting brackets for this hoop are more complicated, as they sit at the intersection of the dashboard and the main tub, and wrap over the sides:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956097_zpspnmyxyym.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956097_zpspnmyxyym.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956094_zpssknxtlsf.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956094_zpssknxtlsf.jpg.html)

I've made them oversize for now, but will fettle them to shape when I've got the hoop ready – they need to be aligned properly. Here's a better view of the four brackets made so far:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956095_zpsspucbqez.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956095_zpsspucbqez.jpg.html)

The last two brackets sit on the top corners of the dashboard frame, and are on the list of things to do this week.


I'll continue the update tomorrow night – steering wheel, gearshift and fire-bottle action!


SB

Here's the rest of the update, as promised.


With the steering rack 90% complete I wanted to continue by making the steering wheel and mounting brackets. The steering wheel was basically the same construction as for the 935, just a slightly smaller diameter (40mm) and a subtly different spoke layout. I cut two pairs of rings from 0.5mm and 0.75mm styrene to create the bulk of the rim, and a final single layer of 1mm for the centre. Notches cut into the 1mm ring would allow me to fit the T-shaped spoke section after I'd finished smoothing and shaping the outer rim. A smear of greenstuff around the inside edge filled the gaps and allowed some stitching details to be added, and some extra pieces of 0.25mm strip completed the joints between the spokes and the rim.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956098_zpsh12z3wwu.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956098_zpsh12z3wwu.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956099_zpsk3ge26bq.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956099_zpsk3ge26bq.jpg.html)

The mounting bracket for the steering wheel is a two-part component – a main bracket which is rivetted to the underside of the dashboard frame, and a smaller block which slips over the column and can be bolted into various positions to adjust the height of the wheel. I'd cut the notch into the dashboard frame some time ago, but had to adjust this a little to get everything in alignment. The ali tube is a placeholder for now, but is about the right length. Since taking this particular photo I've added the outer skin to the dashboard frame and tidied-up around the bracket – I'll show this another time.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956100_zpsaahfzjoj.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956100_zpsaahfzjoj.jpg.html)


Staying in the cockpit, I've made a start on the fire extinguisher bottles. This is another one of those areas where you're torn between making what was correct in-period, or making what's been fitted later. The original drawings I've been working from clearly show two bottles positioned in the passenger side of the cockpit (much as in the 935). One would be piped into the engine bay, the other into the cockpit, so that's what I'm doing. The smaller bottle is made from 15mm till-roll again, the larger one from a length of 20mm diameter nylon rod. I shaped the ends with a combination of styrene tube foundations and Greenstuff, leaving a tube in one end of each to attach the firing head, etc, later.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956101_zps9brv1srr.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956101_zps9brv1srr.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956102_zpsebtvpzzn.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956102_zpsebtvpzzn.jpg.html)

The mounting brackets are in the original 956/962 style and will eventually be incorporated into the floor and crossmember structure. A couple of straps will loop over the top and hold everything in place – these will either be made from aluminium strip or styrene, depending on how I feel at the time!


The final major job I wanted to tackle while on holiday was to get the gearshift underway. Compared to the 935 it's quite a delicate mechanism, particularly the lever and mounting block. It's also the first Porsche model I've built where the gearknob isn't a round ball! The photos tell the story better than I can – the tricky bit was creating the fork on the bottom of the main shift lever, but greenstuff and some fettling work wonders. I'm not intending the mechanism to be functional, so the bent section of linkage through the cockpit doesn't have to mate exactly with the section which will eventually be in the engine bay. I still need to make a tiny rod which connects the lever to the mounting block and provides the second pivot, but that's a job for another time.


https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956103_zpsvyt9ftzc.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956103_zpsvyt9ftzc.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956104_zpsztkoct2b.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956104_zpsztkoct2b.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956105_zpsg0h9xsvv.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956105_zpsg0h9xsvv.jpg.html)


Amongst all these main jobs I've also been spending some time cutting and refining some of the fibreglass and styrene tub panels. Some of this has been prompted by the need to make the brackets for the roll-hoops, but mainly it's just been an opportunity to do some simple-but-satisfying work. Here's a final shot which pulls everything together:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956106_zpsweqahrko.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956106_zpsweqahrko.jpg.html)


One thing I've been thinking about during these last few weeks is how different some of these sub-projects have been, time and effort-wise, compared to the 935-78. The 956 steering column, for example, has taken a fraction of the time – I spent ages getting the different sections of the 935's the right length, making the universal joints, etc. The 935 fuel tank took a long time – making the foam core, adjusting the fit several times into the front of the chassis, panelling it, gluing the fibreglass cloth over the top, painting, etc...whereas in the 956 the fuel tank is hidden inside the tub, so doesn't have to be made! All I will need to make are the filler necks, connection pipework, etc, and that's it. I've been thinking of all the time I spent test-fitting the 935 panels, juggling the engine and gearbox in and out of the frame, even just adding the trackrods to the ends of the steering rack was an exercise in frustration every time! I'm not pretending that there won't be struggles and headaches with the 956 somewhere down the line, but considering I've not yet reached the one-year mark with this project I'm very pleased with the progress I've made.


Have a good week, and hopefully next time I'll have a roll-cage to talk about.


SB

I'm applauding your skill. Terrific update and astonishing scratchbuilding.

Happy New Year, everyone!

A little later than planned, but I've not been feeling 100% for the last few days. Getting back to normal now, so I thought I should wrap-up the progress from 2019.

The main windscreen surround tube for the roll-cage started life as two lengths of plastic-coated wire, bent and persuaded into shape, then two layers of styrene tube sections slid over the top:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956107_zpsjqiln01h.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956107_zpsjqiln01h.jpg.html)

It's not a perfect solution to the problem, but I've not had much luck in the past when I've tried to heat the styrene to bend it to shape. Although my method requires work to fill and smooth the bends afterwards, it does give me a bit of control over the shape.

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956108_zps65rsootw.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956108_zps65rsootw.jpg.html)

The two bends fit into the straight lower sections of the hoop which are glued to the mounting brackets. Lego to the rescue again to try to keep everything in place and at the right angle! The extra tubes to the top corners of the dashboard frame are pinned into the hoop, and there is a small spigot on each bracket for more support. No need to glue this all together just yet, in case of adjustments...

The two main hoops will eventually be connected by a pair of short curved bars, which will define the top inside edge of the door opening. These were made in a similar way to the other sections, but with small socket pieces attached to the main hoops:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956109_zps62lohaay.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956109_zps62lohaay.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956110_zpsjxlmej0v.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956110_zpsjxlmej0v.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956111_zpsahyzlmbd.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956111_zpsahyzlmbd.jpg.html)

I'm reluctant to glue too much of all this together too soon, in case of subtle movements when the dashboard section is finally fixed. The rear hoop is secure enough where it fits over the pieces of ali tube, and the front mountings have been drilled and pinned through into the main tub.

The next step was to return to some of the interior cockpit panels - I decided that I had to glue the inner styrene floor sections in place. This would allow me to start the final trim of the cockpit sides lower edges, and would also lock the floor in place for other work:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956112_zps9okjv8kl.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956112_zps9okjv8kl.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956113_zpsgdl6mo1r.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956113_zpsgdl6mo1r.jpg.html)

I used UHU glue for this, rather than CA - I really want to avoid problems in future if I start applying CA too heavily to thin styrene! You'll also notice that I've put holes in the inner side panels for the cabling, and at the front where the throttle cable will enter. These holes have been transferred to the appropriate styrene panels too.

The last photo tonight is a return of the 'end of year' shots from previous projects, taken on New Year's Eve:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956114_zpshqmtaxlc.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956114_zpshqmtaxlc.jpg.html)

Putting all this lot together made me realise how much progress I'd actually made during 2019. Considering that I didn't start on the tub properly until July, it was a productive second half of the year. Mind you, I wasn't exactly doing nothing in the first half, either - engine core, ox-bow module, and gearbox casing!

So, the immediate plan is to spend a bit more time working on the tub interior detailing, before making a decision on where to focus in 2020. Part of me thinks that with suspension, uprights, hubs, brake calipers, etc to make there's plenty to do without having to worry about moulding fibreglass anytime soon. I've still got a lot of engine-related parts to tackle, too. However, from previous projects I know how much a set of bodywork panels (even in a rough state) can lift the enthusiasm. Hmmm...decisions, decisions!

Thanks for watching, and I'll do my best to keep it interesting!

SB

Looking incredible so far. Always inspiring to see how you can make bits of plain styrene into such a detailed replica.

Mike

You know this next update is gonna be huge. Scratch has been away for a couple of weeks.

No pressure, ferrariman81!

Hello again, everyone. January was a strange month for me - busy at work, family health issues to push through (not my health, but someone very close), and yet the time seemed to speed along. Now it's February, so I'd better show what I've been doing!

I said in the last update that I would start the year continuing with detailing the tub, and that's what I've done. I added a chamfer panel across the top of the cockpit lower crossbeam, and fitted some doubler plates over the wishbone rear leg pick-ups:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956115_zpszylqnxv3.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956115_zpszylqnxv3.jpg.html)

Of course, this meant that I also had to re-trim the lower edges of the inner styrene panels, so there's been lots of filing, trial-fitting, adjustment, re-fitting, etc going on. That's okay, though - I knew they would need to be refined from the original cut.

The next job has been taking up most of my time during January. And it's riveting...

I couldn't avoid the fact that as the 956 has a folded aluminium tub, it also has a lot of rivet heads all over it. I couldn't leave them off, but how to apply them? There was no need for any of the rivets to be structural, so it was purely a case of how to get the right look. Option 1 was to mark the styrene skin panels and apply rivet detailing to the outer surface. Option 2 was to mark and drill holes, then fit styrene rod to create the rivet heads, glue on the back of the panel, then trim flush. Yeah...I went for Option 2!

I knew that Option 1 would mean lots of very small pieces of styrene rod pinging out of my tweezers on a regular basis, causing much frustration. I would certainly end up getting glue all over the outside of each panel, causing more frustration when I eventually start spraying. There was also the probability that this method would see the rivets getting out of line, which would be untidy.

Option 2 has been time-consuming, but I'm very pleased with the results. I've used 0.88mm rod for all the rivets - at this scale I'm not trying to show the difference between different sizes of rivet, even if I could be sure of what the sizes actually were! I started by making a bunch of strips which will eventually be fitted around the interior of the tub, to hide the joints between the vertical inner panels and the sections of floor:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956116_zps0qaa4jhm.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956116_zps0qaa4jhm.jpg.html)

Most of these strips are 2.5mm x 0.5mm; I tried using 0.25mm to get a better scale thickness, but the strips curled up too much, and were very fragile during the drilling process. After this, it was time to start on the various inner and outer skin panels - here's the outer cockpit sides, front sections:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956117_zps0a6imype.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956117_zps0a6imype.jpg.html)

I've used the Freisinger rebuild photos of chassis 956-113 as the main reference for the rivet layout, but when you start looking at all the photos of multiple cars (factory and customer) you notice the small changes here and there. The 962 tub is slightly different again as the years went by, so it's hard to say what's definitive.

Around the front wishbone pick-ups there's a bit of extra angle-section detailing, plus I've made some plates which close-off the very front of the nosebox:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956118_zpsvuqq4aq8.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956118_zpsvuqq4aq8.jpg.html)

More rivets added to the lower panels, plus the upper nosebox side and top plate:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956119_zpsjxy2ram6.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956119_zpsjxy2ram6.jpg.html)

The rear bulkhead panels needed more work - the holes for the lower A-frame pickups needed to be trimmed out, plus the round holes where various pipes, cables and wiring details will be fitted. The hole for the gear linkage needs to be opened up properly, too...and then more drilling and riveting:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956120_zpsttmuwy1p.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956120_zpsttmuwy1p.jpg.html)

Finally for tonight, the sill upper panels needed a bit of fettling and adjustment to the overall shape, and then more rivets...40 holes in each panel:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956121_zps4uakehag.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956121_zps4uakehag.jpg.html)

There's also been more work on the other outer panels, but - as usual - it's only now that I realise I don't have the photos. Something for next time, then. How many rivets so far? At the last count, it's about 615...and rising!

There's still more to do, but I can't avoid doing it. There's more rivets on the front damper mounting beam, the main dashboard frame, and the rear firewall, but the majority are done. Some will be hidden, many will still be visible at the end, so it's worth the effort. I may have to adjust my method for some of the remaining rivets, as some of these last panels have already been glued to the supporting structure - but I'll find a solution.

Sorry for the lack of variety, but it's certainly been a productive start to 2020!

Have a good week,

SB

HA! Knew it.

I applaud your patience in doing all those rivets. Personally, I would have gone nuts.

all that work is so...riveting. :D

i'll show myself the door, but i'll be back. lol!

I applaud your patience in doing all those rivets. Personally, I would have gone nuts.

I agree.

Hello again,

The idea of 'patience' can be a strange thing - I know this project will take several years to complete, I know I will spend weeks (or months) working on small sub-assemblies, and I know that when it's all finished I will put it on the shelf with the others and start the next project. Yet I still get frustrated when something doesn't quite go as I think it should, or when I spend an evening trying to get a particular job done and it goes nowhere. What's the loss of a couple of hours work, when the final total will be several thousand hours?

So, the riveting continues! First up, here's a photo that should have been in the last post - there's a large access hole in the rear sides of the tub which has been cut, and more rivet detailing added to the styrene outer skins:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956122_zpsgxxwn1fd.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956122_zpsgxxwn1fd.jpg.html)

The two main jobs since the last post have been the seat mounting and work on the front damper mounting crossbeam. The seat will attach via a slot in the central spine in the tub, and a bracket on the top of the cockpit sill. The bracket started as short length of angle section, with some strip and plate to create the overall shape:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956123_zpsamsva5t3.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956123_zpsamsva5t3.jpg.html)

A doubler plate was added to the centre spine, with a box-section reinforcement to be fitted to the back bulkhead; there will be more rivet-strips added to the bulkhead above and below the doubler plate. The sill bracket was extended to create more of an 'L' shape, then the ends angled and trimmed to final shape:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956124_zpsttmoogc5.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956124_zpsttmoogc5.jpg.html)

The fibreglass seat shell will have a frame bonded to the back which will line up with slots in these two mountings; I can't work out right now if it has a lower mounting too (or at least some sort of support) - that's something to investigate.

The work on the damper crossbeam has mainly been adding more rivets, and making various reinforcing brackets and plates which will help to hold it in place (although on this model they will mainly be cosmetic rather than structural - the pins into the sides of the tube do 99% of the work):

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956125_zpsyhbywxy6.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956125_zpsyhbywxy6.jpg.html)

Left-hand side, viewed from outside:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956126_zpswoyt6gq7.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956126_zpswoyt6gq7.jpg.html)

Left-hand side, viewed from inside:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956127_zpset8c6y0k.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956127_zpset8c6y0k.jpg.html)

To finish off, I've also added more rivets to the main dashboard hoop, and painted the insides of the various tub cut-outs in preparation for the time when I actually fit the fibreglass panels:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956128_zps1qwhplcy.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956128_zps1qwhplcy.jpg.html)

Total rivet count is now 1063! I must soon start to run out of things to drill holes in...

See you soon,

SB

Fantastic work as always!!

Hello everyone,

I've been working on three main areas since the last post. First up, I wanted to get the pedal mountings and master cylinder arrangement finalised. The two brake cylinders attach via an extension on the front of the chassis tub - I made the core of this extension some time ago, but couldn't finish it until a few other things came together:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956129_zpsfvoe4tlf.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956129_zpsfvoe4tlf.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956130_zps01mm1ho1.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956130_zps01mm1ho1.jpg.html)

The top capping on the extension fits into an appropriate cut-out on the front edge of the top tub panel. The extension itself is not fixed in place yet - I'll eventually paint this part separately to the main tub (the master cylinders too), and it will allow better access to the front end. I've added more rivet detailing around this front area, too.

Inside the tub, I've modified the pedal mountings with some mounting plates and rivet detailing:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956131_zpsttxodal6.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956131_zpsttxodal6.jpg.html)

The next job involved some dramatic surgery to the tub! Both the 956 and 962 have a large access hole in the rear cockpit bulkhead, providing a home for various fuel pumps, etc, and connections to the bag-tank inside. The details of the pump layout vary from car to car (of course!) - more on this later. The original 956's were fitted with a small passenger seat which covered this area, later cars lost the seat but gained a cover panel for the pumps; other photos show the pumps fully exposed in the cockpit. I didn't want to fit the second seat, the cover panel would be the easy option...but having the pumps exposed would be more interesting!

So, I now had to cut into the rear bulkhead to create the opening:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956132_zpsrs4yw2xa.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956132_zpsrs4yw2xa.jpg.html)

I wanted to be careful about reducing the integrity of the existing bulkhead structure, so the hole was re-positioned slightly to avoid the main vertical beam in the middle of the tub - this would become one edge of the hole. I checked my own reference photos and was happy that once the hole was cut there would be enough space behind to fit all the detailing.

After a lot of cutting and fettling, I had this:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956133_zpszh9vjwek.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956133_zpszh9vjwek.jpg.html)

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956134_zpsbd7zvs1a.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956134_zpsbd7zvs1a.jpg.html)

The next job was to tidy up the edge of the hole with greenstuff, then put some thin sheet inside to create the front face of the bag tank. I've also made an oval plate which will be the flange where all the pipework will connect. After this, I made a start on the fuel pumps themselves:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956135_zpsxhomcfcp.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956135_zpsxhomcfcp.jpg.html)

...and with a bit more work:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956136_zpshgxxtu2c.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956136_zpshgxxtu2c.jpg.html)

The exact arrangement of the top fuel rail and other pipework does appear to vary greatly - inevitable, really, when so many of these cars were run by privateer teams in period, and with various updates from the factory when new. The very first 1982 cars used a mechanical fuel injection system, but from 1983 they introduced Motronic injection - I can't find any appropriate photos of the '82 works cars pumps (because of the seat, cover panel, etc), so it looks like I'll be making an '83-onwards car!

I spent most of the evenings last week making a selection of components for the various fuel line fittings - sockets, spacers, various wire bends, etc. I've made enough bits now to put together about twenty-five fittings, but I'll wait until I've finalised the exact layout.

The hole in the fibreglass panel is not at final size yet - I'll have to make a separate fibreglass flange and lip which will frame the opening, but you can see how the pumps will sit inside:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956137_zpssmmdpbg2.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956137_zpssmmdpbg2.jpg.html)

The final job for tonight is a return to something I started several weeks ago - a dummy front lower wishbone. I've mocked this one up from 1/8" styrene tube and an RC balljoint on the end - the overall shape is basically right, but the final construction will be much improved! I've devised a way of creating a flexible joint at the two inner ends (small diameter rubber hose, smaller diameter ali tube, a brass pin, and a couple of styrene shims) and the box-section socket on the rear leg should allow me to assemble the complete wishbone off the car, then glue the whole lot in place:

https://i604.photobucket.com/albums/tt121/ScratchBuilt917/Scratchbuilt%20956/956138_zpsnivmtrre.jpg (https://s604.photobucket.com/user/ScratchBuilt917/media/Scratchbuilt%20956/956138_zpsnivmtrre.jpg.html)

I'm currently adding a styrene skin to the fibreglass area around the rear leg - this will finalise the position of the socket and provide a little more clearance between the wishbone leg and the side of the tub. Once I've got this lot under control I can do some more trimming on the fibreglass floor panel, and maybe even glue it in place - if I can convince myself that this won't cause me a problem somewhere down the line! My main worry is whether it will make it harder to spray the inside of the tub...we'll see.

That's it for tonight. Not sure what the next update will contain - I feel as though I should be making moulds for more fibreglass panels, but there's more than enough to be getting on with the rest of the car. I somehow get the feeling that I won't be going to too many race meetings (or Le Mans) this year...

All the best,

SB

Nice update! And part of me kept thinking how many lph will those pumps you made run heheh

Mind blowing! Your craftsmanship is superb, as usual. Keep plugging at it. You are an inspiration to all of us.