1/8 Porsche 908/03

[ScratchBuilt]

Hi Keith,

Although I used templates to hotwire the foam blocks to make the sill moulds, there were small variations between them. On the main bodymould I used filler, etc, to produce the final surface, but the sills are a much simpler shape. The cardboard outer layer just gives a nice even surface across the whole mould. With this method it took maybe a morning's work to make the two sill moulds - using filler would have taken much longer, and the surface still wouldn't have been as good.

On the 917-10 I sanded the body as it came off the mould, but still had to apply a thin screed of filler in some areas to get a paintable surface (plus several sprays of primer, etc). On the 908 I'm trying to keep on top of it as I go along - sanding down any faults between applying each layer - so hopefully the finished shell will be an improvement. I bought some 0.6 ounce cloth yesterday which will probably be used as an outer layer, plus I'm tempted to add a final topping of resin to act as a filler. I'm sure that whatever I do I'll still need to spend some time cleaning up the surface before painting.

This is my concern about applying the technique to smaller scales - there's less margin for error! Even using the finer cloths I think it would be very fiddly to create all the small details you'd want on, say, a complete 1:24 body (and being able to make it stong enough). Plus you've still got to make the mould / pattern to start with. I was going to make the fan shround for the 908 as a moulding, but decided that it would just be quicker and easier to build it up using greenstuff and plastic...

Having said that, I guess there's people out there casting small pieces in resin, so maybe it would work - it might just need a few practice attempts on simple shapes. There are some small ducts, etc, on the 908 - these might be the excuse I need to try fibreglassing them, rather than making from plasticard or tube. Experimentation is required!

Cheers,

ScratchBuilt

[keefr22]

Originally Posted by ScratchBuilt

Experimentation is required!

Absolutely!!

Thanks for the reply SB!

Keith

[ScratchBuilt]

Hello!

Since the last post I've been able to finish laying-up the main tail / door section, and made the nose section. I can now start positioning and trimming the panels - cardboard templates taken from the original line drawings help, but mainly it's just a case of getting the sill panels located, then offering everything else to match. The tricky bit is that the sills flare out towards the rear, so I have to create an adjustable mounting. I'll post some shots of the chassis later in the week, but for now, here's the body panels being mounted:







See - I said it would start to look like a 908-03!

ScratchBuilt

[gasdriverca]

Great work I'm lovin it!!

[keefr22]

Originally Posted by ScratchBuilt

Hello!

See - I said it would start to look like a 908-03!

ScratchBuilt

It looks EXACTLY like an old racing Porsche - raw, translucent see-through fibreglass!! Brilliant stuff!!

Keef

[cinqster]

Whuhoo...fantastic work! I love that grp bodywork. I guess you used matting rather than cloth?

[TRBJ]

dude are u gonna be selling that car? hehehe

[ScratchBuilt]

As promised last night, here's a couple of shots of the sill frame extensions:





The lengths of 1/4" angle are not yet fixed in place - I need to make sure they line up with the main top bodywork section. The tubular frame on the left-hand side of the engine bay will also support the main oil tank. The exact detail of these frames varies - some of the '71 cars don't have the top diagonal on the right-hand side - but the white 'Brunn Racing' chassis ('70) does, and that's good enough for me.

Keef: yes, I like the way the chassis shows through the fibreglass; I dread to think how thin the full-size panels are!

Cinqster: the fibreglass is more a 'cloth' rather than the sort of chopped-strand matting you might use on full-size bodywork. The nose section is made from a layer of 0.6-ounce, then 1.0, 1.5, 1.0 and a final top layer of the 0.6 - and you can still see through it...

Right - now for another trimming and fitting session!

ScratchBuilt

[corydos63]

incredible work!!!!



wow!!!!!!

[Decs0105]

simply brilliant!

[Taka-Q]

ScratchBuilt,

Thank you so very much for taking the time to post your progress. It is absolutely inspiring. Please don’t take for granted that what you do for fun is a very high level of skill and craftsmanship.

Also, It’s so kind of you to acknowledge so many comments, questions, and “constructive” criticisms, although I myself cannot see viewing Michelangelo’s Pieta, and commenting that Mary’s left shoulder is offset “by a small but critical amount”.

Finally, may I ask, please, what technique(s) you have found to be the best for cutting non-geometric / freeform curves in sheet styrene? My bench-top scroll saw's blade creates so much heat, by friction, that it actually "welds" the plastic back together, just behind the blade and cut that I'm making. I typically use about 1/8" thick sheet.

I would very much appreciate any comment you, or others may choose to make.

Thanx,

Taka-Q

[ScratchBuilt]

Hello again,

Apologies for not updating for a little while - I've been making progress, but I've been waiting before posting new photos. I'll put these up in the next day or two. The other reason is that I've been away at the Le Mans 24hr since the middle of last week, returning home late last night. A fantastic event, as I hope any of you who have ever been will agree!

Taka-Q: I use four different thicknesses of styrene sheet - 0.01" (0.25mm, white), 0.017" (0.044mm, black), 0.02" (0.5mm, white), and 0.04" (1.0mm, white). Mostly it's the 0.02", but the black 0.017" is good for providing an instant undercoat, so I'll use this for the floor, engine bay panelling, etc. All three of the thinner sizes cut fine with a knife, scissors, compass-cutter, etc, but the 0.04" is hard work. It only gets used where absolutely necessary! I bought a pair of nail scissors with curved blades - these are particularly useful - as I couldn't find proper 'modelling' curved snips.

Unfortunately, I don't have any experience of cutting styrene sheet thicker than the 0.04". If it's the heat that's causing the problem, I guess one engineering solution would be to use some sort of cutting fluid / lubricant. One of my jobs at work is to cut race-car windscreens from 1.5mm and 2mm 'Makrolon'-type sheet - for this I use an air-powered cutting disc normally used for trimming fibrgelass bodywork. Even with this you notice the difference between the 1.5 and 2mm sheet, so I can imagine 3mm being a struggle.

Anyone else have any suggestions?

ScratchBuilt

[rhb]

Originally Posted by ScratchBuilt

Anyone else have any suggestions?

ScratchBuilt

Yes
Look here
http://hackedgadgets.com/2008/03/15/...ewing-machine/

mvgrijk

[cinqster]

Nice progress Scratchbuilt! Glad you also enjoyed Le Mans - just got back as well!

Love to hook up for a natter if you're going to Goodwood FOS on the Friday! Can't send/recieve PM's on this website though - grrrrr!

[cinqster]

Originally Posted by ScratchBuilt

Anyone else have any suggestions?

ScratchBuilt

One of these, a good eye and plenty of time and patience!

http://www.dave-cushman.net/bee/piercingsaw.html

I've cut through 1/2" cast iron with one of these puppies.