Hi there,

What is the metric name for the tube, which is used in the frame. Is that 25x25x2 or what else.

Is it all the same, or are there more kinds of tubes in the same frame?

Do you have the book? If not, 1"x1" ERW is 25mmx25mmx1.6mm tube. You will also need 19mmx19mmx1.6mm, and 19mm round tube (1.6mm), some 3mm plate, some 50mmx50mmx3.25mm ERW for making brackets

ok great,

I do have the book, but could find de metric dimensions.

Thanks

do you know how many lengths of each size are needed, I think a length is 6m?

Chris,

check out

http://mcsorley.net/locost/default.htm

You'll find the corrected diagrams (the book has some dimentions wrong in it) and a cutting. I have used the book chassis design and cutting list and all dimentions are perfect, the cutting list calls for 11 lengths of 120" (all measurements are metric and imperial, each piece of steel has it's own engineering drawing)

My chassis was done with this and it's spot-on, you will however need the book for the TR tubes as the are not on the digrams

Simon

cheers Simon, will order the materials tomorrow. building starts ASAP!

Once you've decided to go with regular steel tubing instead of something a little more exotic like stainless, how important is it that you know what type of steel alloy you want?

I've run across descriptions of low-, medium-, and high-carbon steels with number (in North America) that start at 1010 and go up from there (1020, 1040...).

I've also heard that some builders recommend "Drawn-Over Mandrel" (DOM) ERW for extra strength for the suspension parts.

Any concerns about this?

Thanks
Kevin B.

Kevin, you won't have much choice of steel grade in Square ERW sections..just use what they have....


Also, FYI. DOM starts off as ERW but is then drawn down to smaller sizes...it is considered to be virtually as good as seamless...many racing organizations consider it equivalent for roll cages etc....it also is more uniform wall thickness.

I would suggest u use CDS (cold drawn seamless) for the wishbones, better tensile strength
Shug.

I can't remember where I was reading it, either something by Darren George or Jim McSorley I think, but it talked about 1" and 25mm square tubing as being slightly different sizes and that it could cause problems with the slight changes in dimensions. I seem to remember a mention being made that a good, comprehensive steel stockholder would have both types available.

Sorry I can't be more specific.

Most posts that I've read indicate that 1010 is marginal, 1020 is entirely adequate, and above 1040 you're showing off.

It also seems many builders feel that the alloyed steels, like 4130 chrome-moly, are overkill.

Even if I don't have much choice on what the local dealer has, it still seems worthwhile to at least know what is going into my chassis.

I heard that DOM was a post-formed type of ERW, but I don't think I've heard of CD$ before. Is that code for "unobtainium"?

Kevin B.

Cold drawn seamless is exactly what it says on the tin, no seams no welds. I know engineers in Canada/U.S. that use it
Maybe Im a muppet but I thought it was universally available, and its only slightly more costly but worth the expense IMHO, we build the whole chassis in CDS btw.
Shug.
P.S. My Brother is in Alberta, will ask him tonite where he sources his stuff, designer with an engineering company in Calgary.

[Edited on 5/1/04 by Hugh Paterson]

Hugh Paterson:

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I would suggest u use CDS (cold drawn seamless) for the wishbones, better tensile strength

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I'm guessing that CDW and DOM are probably the same?......it certainly seems they are made the same....ERW tube that is redrawn........probably a nomenclature difference between the US and elsewhere......

A good place to source CDS is West Yorkshire Steels http://www.westyorkssteel.com/ they deliver for a quite reasonable price as well ... cost me £7.50 for about 40Kgs worth. They are also good for more specialised alloys.

One thing to check is that you don't end up with the DOM tube used by hydraulics people - its designed to be bent so not the best stuff to use!

[Edited on 6/1/04 by Matthew_1]

Is CDS any more difficult to weld than ERW, due to it's higher strengh?

Steve

My chassis is built almost entirely from 1" CDS tube and the welding was just the same as with ERW - though I'm now using ArgoSheild Lite which makes everything much neater than the disposable bottles that last about 5 minutes.

The hardest part is cutting fishmouths, I've now wrecked 3 1" holesaws on my drill press cutting the damn things out!!

Alan B:

quote:

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I'm guessing that CDW and DOM are probably the same?

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