Printable Version | Subscribe | Add to Favourites
New Topic New Reply
Author: Subject: ERW or CDS?
Jesus-Ninja

posted on 18/8/08 at 11:10 AM Reply With Quote
ERW or CDS?

As per the title...





Suspension geometry tool here >>> http://www.locostbuilders.co.uk/viewthread.php?tid=81376

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Marcus

posted on 18/8/08 at 11:19 AM Reply With Quote
ERW





Marcus


Because kits are for girls!!

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
Jesus-Ninja

posted on 18/8/08 at 11:24 AM Reply With Quote
quote:
Originally posted by Marcus
ERW


because...?





Suspension geometry tool here >>> http://www.locostbuilders.co.uk/viewthread.php?tid=81376

View User's Profile Visit User's Homepage View All Posts By User U2U Member
nick205

posted on 18/8/08 at 11:27 AM Reply With Quote
...it's cheaper!






View User's Profile View All Posts By User U2U Member
flak monkey

posted on 18/8/08 at 11:30 AM Reply With Quote
CDS is unnecessary for a chassis, and also not really a requirement for suspension parts either (with careful positioning of the seam).

David





Sera

http://www.motosera.com

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Alan B

posted on 18/8/08 at 11:30 AM Reply With Quote
How can you ask someone to elaborate upon an answer to such a vague question?
View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
Jesus-Ninja

posted on 18/8/08 at 11:35 AM Reply With Quote
quote:
Originally posted by Alan B
How can you ask someone to elaborate upon an answer to such a vague question?


Fair comment

It's been suggested to me that I should use CDS rather than ERW as it is significantly stronger for the same guage.

Strikes me that the chassis is the one thing you get one pop at, so it may pay dividends to go CDS.





Suspension geometry tool here >>> http://www.locostbuilders.co.uk/viewthread.php?tid=81376

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Alan B

posted on 18/8/08 at 11:43 AM Reply With Quote
quote:
Originally posted by Jesus-Ninja
quote:
Originally posted by Alan B
How can you ask someone to elaborate upon an answer to such a vague question?


Fair comment

It's been suggested to me that I should use CDS rather than ERW as it is significantly stronger for the same guage.

Strikes me that the chassis is the one thing you get one pop at, so it may pay dividends to go CDS.


First of all CDS is NOT significantly stronger, and as Flak says used correctly ERW is fine for most applications.

Also, have you actually looked for and found CDS in square section?...not saying it's not made, but it is very rare and hard to find..I think I've only ever seen it in chromoly.....and so very expensive.

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
smart51

posted on 18/8/08 at 11:50 AM Reply With Quote
I've seen plenty of pictures of crashed kit cars. Never have I seen the seam of a tube split. Maybe it can happen but then aren't the tubes held to each other by weld?

I'd be tempted to use CDS if using thinner walled tube. The extra cost of making it might be offset by the lower material cost.

[Edited on 18-8-2008 by smart51]

View User's Profile View All Posts By User U2U Member
Jesus-Ninja

posted on 18/8/08 at 11:51 AM Reply With Quote
Thanks guys! I'll leave my order for ERW as is then!

[Edited on 18/8/08 by Jesus-Ninja]





Suspension geometry tool here >>> http://www.locostbuilders.co.uk/viewthread.php?tid=81376

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Peteff

posted on 18/8/08 at 04:09 PM Reply With Quote
Where can you buy CDS in square section? I've only seen it in round and ERW in round, rectangular or square.





yours, Pete

I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.

View User's Profile View All Posts By User U2U Member
Jesus-Ninja

posted on 18/8/08 at 04:15 PM Reply With Quote
quote:
Originally posted by Peteff
Where can you buy CDS in square section? I've only seen it in round and ERW in round, rectangular or square.


I dunno! I don't even know if the place I ordered it from does it. But I got a mail from a friend (who knows a thing or two)


quote:

If you can change that to CDS rather than ERW, I would if I were you. CDS is nearly twice as strong for the same size although it will be more expensive. I'm pretty sure that like for like the difference in strength is a factor of 1.8/1.9



Hence my questions

Still, sounds like ERW is fine. So I have a great pile of steel arriving tomorrow!





Suspension geometry tool here >>> http://www.locostbuilders.co.uk/viewthread.php?tid=81376

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Rasteirinho

posted on 20/8/08 at 01:00 PM Reply With Quote
Sorry, but what ERW and CDS means?





'99 Mitsubishi Lancer Evo VI RS2
'85 Toyota Corolla GT TwinCam

View User's Profile View All Posts By User U2U Member
Alan B

posted on 20/8/08 at 04:26 PM Reply With Quote
quote:
Originally posted by Jesus-Ninja
quote:

If you can change that to CDS rather than ERW, I would if I were you. CDS is nearly twice as strong for the same size although it will be more expensive. I'm pretty sure that like for like the difference in strength is a factor of 1.8/1.9




What a load of bollocks..

The question was a comparison of production method. CDS is NOT inherently any stronger ERW.

Now if you are comparing different metalurgical specs...that's a different story..but ERW and CDS of SAME material have very similar mechanical specs.

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
iank

posted on 20/8/08 at 04:35 PM Reply With Quote
quote:
Originally posted by Rasteirinho
Sorry, but what ERW and CDS means?


ERW = Electrically Resistance Welded
CDS = Cold Drawn Seamless.

There is also DOM (Drawn over Mandrel) to add some more confusion.

It's the way the tube is made, ERW is made from a sheet which is folded and then welded so it has a noticeable seam where CDS is manufactured without a seam.
DOM is ERW that is then processed to smooth down the seam.

It's theoretically possible in a crash for a seam to split, but in reality, if your chassis is well designed, if it does you have a lot more to worry about as you'll already be dead from the shock loads of the massive deceleration you'll have been through.





--
Never argue with an idiot. They drag you down to their level, then beat you with experience.
Anonymous

View User's Profile View All Posts By User U2U Member
rgdavid

posted on 2/1/09 at 07:14 PM Reply With Quote
specs for steel tube

good evening,
could someone please give me the materiel specs for ERW chassis making square tube, in BS or europeen or prefrably french standards (cos i live in france),
this would be a great help to find the equivalant here to order my tubes, thanks & happy new year!, david

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
alistairolsen

posted on 8/1/09 at 02:48 PM Reply With Quote
so cds isnt worthwhile for a chassis,how about for wishbones?
View User's Profile Visit User's Homepage View All Posts By User U2U Member
Hugh Paterson

posted on 8/1/09 at 06:35 PM Reply With Quote
Depends on who u ask (as always), IMHO CDS is "ideal" for wishbones, but I have also used ERW. If cost is not an issue, I would use CDS however and recommend its use to customers
Shug

View User's Profile E-Mail User View All Posts By User U2U Member
alistairolsen

posted on 8/1/09 at 07:08 PM Reply With Quote
quote:
Originally posted by Hugh Paterson
Depends on who u ask (as always), IMHO CDS is "ideal" for wishbones, but I have also used ERW. If cost is not an issue, I would use CDS however and recommend its use to customers
Shug


Id agree on it being the ideal solution, but since cost is always an issue except in F1 Im wondering what I can get away with without compromising safety!

I dont want to make any decisions that might cause injury to me or my passengers, but if I can safely halve the costs of my wishbones then I will!

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Hugh Paterson

posted on 9/1/09 at 06:17 PM Reply With Quote
Hi Alistair, I would suggest for the cost of buying enough CDS to do your wishbones its a "no brainer" have u been given a quote?
Shug

View User's Profile E-Mail User View All Posts By User U2U Member
rgdavid

posted on 14/1/09 at 04:20 PM Reply With Quote
quote:
Originally posted by rgdavid
good evening,
could someone please give me the materiel specs for ERW chassis making square tube, in BS or europeen or prefrably french standards (cos i live in france),
this would be a great help to find the equivalant here to order my tubes, thanks & happy new year!, david


Bump , helpy help please, thanks, dave

[Edited on 14/1/09 by rgdavid]

[Edited on 14/1/09 by rgdavid]

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
Peteff

posted on 14/1/09 at 09:05 PM Reply With Quote
It's just mild steel 25x25 with 1.5mm wall thickness Dave. Nothing special or exotic is needed. You might have to have 2mm wall but it isn't going to make that much difference overall.





yours, Pete

I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.

View User's Profile View All Posts By User U2U Member
rgdavid

posted on 15/1/09 at 12:40 PM Reply With Quote
thanks,

thanks a lot, but quite suprised its nothing special,
i use EN 10219 S-235JRH everyday for making gates etc, its nothing special at all !
trying to find a grade between that & 25cd4s

love your signiture !
all ze best, dave

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member

New Topic New Reply


go to top






Website design and SEO by Studio Montage

All content © 2001-16 LocostBuilders. Reproduction prohibited
Opinions expressed in public posts are those of the author and do not necessarily represent
the views of other users or any member of the LocostBuilders team.
Running XMB 1.8 Partagium [© 2002 XMB Group] on Apache under CentOS Linux
Founded, built and operated by ChrisW.