View Full Version : Building my own tube frame

29-07-2007, 03:24 AM
Just bought myself a Cimbria Body... no frame or powerplant. I'd like to start with a tube frame. Anybody have some words of advice? Any websites to visit? Anything I should look for or stay away from? How close is the Cimbria body to the Nova/Sterling

29-07-2007, 05:19 AM
This should give you a start http://www.rorty-design.com/content/beetle.htm

Also Dave at Stirling Sports Cars would make you one. See his Web Site for details. http://www.sterlingsportscars.com/index/index.html


29-07-2007, 04:05 PM
Hey Scott,
You and I have gone back and forth a little privately, but any information shared here is equally important. You bought the first generation Cimbria, which shares the same basic body-plan as the Sterling/Nova. In other words, the perimeter of the body will rest on top of the Beetle chassis. The Rorty chassis is pretty good, though I don't know how high that center roll bar goes in relation to a basic kit body. Berrian Chassis also makes tube frames, albeit for the buggy crowd. I think Dave talked to them at one point about making his chassis', but they would not manufacture a full length chassis. Something about too much flex in the middle.

Anyway, I'm excited for you! This should be the beginning of some interesting conversations and photos!


31-07-2007, 07:51 AM
Hello Scott, and welcome to the fold. Not many of us tube-frames about, but that shouldn't stop you from having a go.

The Cimbria, with its gull-wing doors has less side sill depth in which to hide large triangulated sections, so the stock VW bug replacement chassis may be more appropriate. To be honest though, for the amount of modification required, you may as well start from scratch.

My starting point was exactly the same as yours - I took my Nova body off the VW chassis and then carefully measured up all the body flange dimensions and then drew a basic chassis plan around that. I don't know if the Cimbria body flange slopes uphill at the front like a Nova does (to cater for the stock VW pan sitting up higher at the front when the steel body is removed), but you should check before cutting metal. Try propping the body horizontally and checking whether the flange is also horizontal (or not). I had already decided on an engine/transaxle package and having the hardware lying around allowed me to determine bulkhead positioning and assess how much cabin space I had to fit into!

What mechanical specification have you got? Rear engine/transaxle (as per original, but with a replacement tube frame), or mid-engined? What suspension set-up will you be using? The custom boys like to use the Mustang II IFS, with rack and pinion steering, which would be a good start. The Mustang II/Pinto front track is wider than the VW, so you don't need to go silly on front wheel offsets to fill the arches. Shame about the scrub radius though (only 4 KPI if its anything like Ford Europe :( ).

I guess with the current crop of transverse FWD engine/transmission packages there is plenty to choose from, although I did hear that typical US V6 engines could be hard to conceal under the rear deck (Mike McBride was considering a Fiero set-up at one stage, but rear vision was virtually nil).

Scooby boxer engines offer a great deal to the prospective designer, but if you want to go mid-engined (and retain any semblance of reasonable gear ratios), a suitable transaxle becomes an issue. Maybe use a Scooby gearbox with just the front wheel drive connected (not sure how this would effect torque distribution though).

And wishbones at the back, or struts? Better geometry with the former, but if you keep the weight down, struts are perfectly acceptable, and offer longer travel for street use.

I was a complete novice at this sort of thing (still am in many respects), but I got a copy of "How to make your car Handle" by Fred Puhn (bought my copy in LA) and Allan Staniforth's "Race and Rally Car Sourcebook", and read them cover to cover, and that was enough. If I can do it, anyone can :D

The world is your donut!

Good luck with whatever you decide to do, and keep us posted on your progress!


31-07-2007, 06:35 PM
Just remember 70% of kit cars never get completed because owners expectations exceed their limitations, in time, cash and skill. Only plan to undertake what you KNOW you can do, not what you would LIKE to do.

01-08-2007, 07:02 AM
Wise words indeed, Peter. I've seen too many half-finished projects in my time (Green Machine was nearly one of them!), and not all of them Nova/derivatives either!!!


15-08-2007, 09:40 PM
Hiya Peter

Yes that is what I call the Nova wall. I did post it like wen you put in too much time effort and cash. But I have learnt (the big baseball bat) called life can get in the way as well.