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Old 12-03-2019, 01:57 PM   #46
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Re: 1/8 Porsche 956

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.





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.




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.





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.









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:




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
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Old 12-03-2019, 10:40 PM   #47
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Re: 1/8 Porsche 956

I'm applauding your skill. Terrific update and astonishing scratchbuilding.
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Old 01-06-2020, 02:41 PM   #48
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Re: 1/8 Porsche 956

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:



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.



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:







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:





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:



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
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Old 01-07-2020, 07:42 AM   #49
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Re: 1/8 Porsche 956

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

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Old 02-01-2020, 02:43 AM   #50
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Re: 1/8 Porsche 956

You know this next update is gonna be huge. Scratch has been away for a couple of weeks.
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Old 02-04-2020, 04:12 PM   #51
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Re: 1/8 Porsche 956

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:



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:



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:



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:



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



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:



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:



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
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Old 02-06-2020, 06:00 PM   #52
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Re: 1/8 Porsche 956

HA! Knew it.
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Old 02-08-2020, 04:17 AM   #53
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Re: 1/8 Porsche 956

I applaud your patience in doing all those rivets. Personally, I would have gone nuts.
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Old 02-09-2020, 12:50 PM   #54
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Re: 1/8 Porsche 956

all that work is so...riveting.

i'll show myself the door, but i'll be back. lol!
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Old 02-10-2020, 10:52 AM   #55
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Re: 1/8 Porsche 956

Quote:
Originally Posted by malscar View Post
I applaud your patience in doing all those rivets. Personally, I would have gone nuts.
I agree.
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Old 02-17-2020, 01:50 PM   #56
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Re: 1/8 Porsche 956

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:



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:



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:



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):



Left-hand side, viewed from outside:



Left-hand side, viewed from inside:



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:



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

See you soon,

SB
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Old 02-20-2020, 01:22 AM   #57
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Re: 1/8 Porsche 956

Fantastic work as always!!
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Old 03-16-2020, 03:57 PM   #58
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Re: 1/8 Porsche 956

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:





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:



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:



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:





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:



...and with a bit more work:



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:



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:



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
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Old 03-17-2020, 05:08 AM   #59
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Re: 1/8 Porsche 956

Nice update! And part of me kept thinking how many lph will those pumps you made run heheh
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Old 03-17-2020, 11:59 AM   #60
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Re: 1/8 Porsche 956

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