Custom Tubular Wishbones advice needed.

[MasterAuron]

I be giving my new front wishbones with Powerflex bushes an extra lick of paint today and something crossed my mind...Having a pair of tubular wishbones made.

This is a standard Mk1 Punto wishbone:

Now, I'm sure it wouldn't be a very hard job to fabricate a tubular wishbone to fit the car. Due to it's tubular nature and material I'm sure a wishbone of this fashion would not only be much lighter than the cast item, but stronger too. I was thinking something like this:

Due to the safety implications of such an item, I'm not prepared to have a go myself. Does anybody know what sort of company to approach regarding getting a pair designed and made? Rough cost? I'm hoping to keep costs as low as possible.

Also, with rose joints on the hub ends I can adjust camber without the camber adjustment bolts.

Opinions and advice much needed please?

 

[obi_waynne]

An interesting proposition, it would take some precision machining to fairly high tolerances. Doesn't anyone already fabricate ligther wishbones for these?

The tubes might be stronger but the joints will be a weakspot, I'd guess that you'd need a tube bent into a right angle rather than just using 2 straight tubes.

 

[MasterAuron]

An interesting proposition, it would take some precision machining to fairly high tolerances. Doesn't anyone already fabricate ligther wishbones for these?

The tubes might be stronger but the joints will be a weakspot, I'd guess that you'd need a tube bent into a right angle rather than just using 2 straight tubes.

No chief, nobody makes these already, otherwise I'd just buy some I don't think it's beyond even your average engineer tbh.

Looking at other wishbones of a simular design already avaliable (for other cars) many use two opposing tubes joined with a weld. Don't forget the strengthener will reduce stress on this point. It's not a particularily heavy car or engine either. I think a single tube with such a sharp bend is a bad move, it's just going to want to carry on bending under load when it's on the car. OG will know about all this sort of stuff surely?

 

[Turboshaft]

If it won't be too late , I'll be back in UK at the end of august and i'll get in touch with the folks at the formula sae racing team, they get a lot of tubular wishbones machined to their specs and i might be able to get a hint or two as i'm also interested in a tubular double wishbone kit.

 

[dpsubaru]

in brief yes it can be done, have pm'd you.

 

[old-git]

No chief, nobody makes these already, otherwise I'd just buy some I don't think it's beyond even your average engineer tbh.

Looking at other wishbones of a simular design already avaliable (for other cars) many use two opposing tubes joined with a weld. Don't forget the strengthener will reduce stress on this point. It's not a particularily heavy car or engine either. I think a single tube with such a sharp bend is a bad move, it's just going to want to carry on bending under load when it's on the car. OG will know about all this sort of stuff surely?

Err, thanks MA

This is part of the suspension that I have left to the experts as I don't want to die through my own stupidity.

On my project car I have replaced the standard Elan front unequal length mild steel U section wishbones with adjustable tubular race versions. I have kept the rear lower A frame and added adjustable H shaped tubular top frames, made by a race car designer and builder.

The Punto item has to handle both steering and transmission forces and looks pretty well made with half an eye on reducing weight in its standard form. How much weight do you reckon you can save?

 

[Loz]

Force racing do some nice goodies, they might make something up if you ask them nicely. :bigsmile:

http://www.force-racing.co.uk/non-mini-components/

 

[herb]

I'm working in a steel fabrication place today and I asked 1 of the blokes and he said if you can make a drawing with dimensions if could knock 1 up in no time and it wouldn't cost much
Hope this is of help mate?

 

[old-git]

I'm working in a steel fabrication place today and I asked 1 of the blokes and he said if you can make a drawing with dimensions if could knock 1 up in no time and it wouldn't cost much
Hope this is of help mate?

Hmmm...Knocking up something as critical as a suspension part scares me. Personally, I wouldn't trust my life to anyone not skilled in race car suspension fabrication. The stresses on parts are complicated so if you don't know what you are doing you are asking for trouble. Also welding quality control for the general construction industry is nowhere near as good as that required for highly stressed suspension components.

 

[MasterAuron]

Lots of helpful advice here. I'll look into a few things and then report back. Definately want it done by a pro though tbh for the very reasons OG has stated. Reply properly tomorrow, just on for a small update on the punto thread then off for a shower!