Hello people,

As everyone on here seems far more in on the locost gag than me I wonder if any of you can tell me if the material for the chassis is simply mild steel or are slightly more exotic cro-molys like reynolds 531 etc preffered?

I am thinking about racing the beast when shes finished so it needs to be racing legal but neither 'the book' nor the racing regs appear to specify the grade of steel that must be used....

Any help much appreciated...

it's just mild steel, but i don't know about racing regulations.

When I started, I had trouble even finding the right type of Steel!

The book says that all the Steel is RHS
(which is tricky becuase none of it's rectangular) but I couldn't find anywhere
that could supply RHS in anything under
2mm.

Eventually, after making a fool of myself
at a few Steel suppliers, I found and article on this site that explained it all.

Apparently, the steel you want is called
ERW (which means that it's folded then electro welded down the seam)

I bought all my steel for about £120 from
a local supplier....and it's mild steel, which
is OK for the 750mc series

Hopefully be racing you next season then!

Good luck..

JohnB

[Edited on 14/6/03 by burgessj]

Don't forget though ALL square tubing is made that way...even RHS....

Unless, of course, someone can show me that there is some square seamless...I've never heard of any....


Just a matter of terminology more than anything else really.....

But, yes...ERW is what you need.

£120 for mild steel?
I paid £127 for mine, but it is stainless.
Think of all that money I'll save on paint.

really? I thought stainless cost way more than mild.. sheet does, anyway. where did you get your stainless rhs?

I'm lucky, I work for a company making chemical plant, so I tack my orders onto bigger orders so I pay "price per tonne".
e.g. 6m of 1/2" NB Sch 10 s/s pipe
(wishbones) = £27.00
My car so far has cost me £3000, (almost
a rolling chassis) but seats, coil overs and my beloved Lotus engine is half of this.

ah, you lucky devil. Then again, I have a friend who works for penn fabrication and can laser / punch / bend / etc sheet stainless for bits as I need them.. and says I can use their acid shower.. so I'm not luck-free myself

Another note, is stainless just as suitable for a chassis as mild? iirc it's harder.. just wondering if it suffered from fatigue more or something nasty like that..

no real reason to assume it does, but it sounds like the kind of thing someone on here would say after I built a chassis out of stainless and it snapped

i know bugger all about metalurgy, but have heard it said on other forums that stainless is prone to cracking in a locost application.

just relaying the info.

could be bollox

atb

steve

Yes you've got me there; it is more prone
to fatigue, but thin wall mild steel rhs rusts from the inside out. A bit long term
all of this, don't think we need to worry.
I'd stay out of that acid shower if I were
you and stick to Imperial Leather.

The are many grades of stainless, I cannot remember which are the least prone to cracking.

If I was going to do it all again, I would buy one of those inverter TIG's from Machinemart and use stainless of the correct grade (and make it 2" wider!)

Inverter TIG's come highly recommended.
Best thing since sliced bread. Make sure
its got HF or you might regret it later.

I did 25% of the stainless welding on the mullions for the roof of Canary Wharf with a scratch start inverter TIG, it's no problem once you have got the hang of it!!