burnsey

I have just started prepping my Ap1 s2000 ready to race, it is off the road and will be a fully dedicated track/race car, at the moment it is stripped and ready to have a full roll cage fitted.

I have had a read on here and also spoke to a few people about it, but had mixed opinions and still can't decided whether to stitch weld or not, So I am looking for someone who has stitch welded their S2000 or knows of anyone who has done it, who can provide some good feedback into helping me decide what to do. Basically I want to know is it worth it, or will it just be a waste of time and ruin the car as I have heard you can over do welding, also if known what are the key areas to stitch weld to get the best results.

s2000ellier

You should reweld the stamped front upper A-arms supports. I tore those without using slicks (I have an AP1). I can't speak to stitch welding the whole car though.

https://www.s2ki.com/s2000/topic/111...ld-failure-fix

burnsey

This is one of the things to do on my list , Cheers

1tuffbb6

Not to thread jack, but this could be an opportunity to discuss 'Seam welding' versus 'Stitch welding.'

I am interested to see if anyone has hands on advice on which works better and why.

And to answer the OP's question... to see if something is 'worth it,' I think there should possibly be a dollar amount associated in measuring the actual value of this service. I have always wanted to do this, and plan to in the future, but I only care to do it by myself. The entire process a shop would probably charge astronomical amounts for. An extra $1,500.00 to maybe shave a .002 of a second, and possibly add to the longevity of the unibody... doesn't really seem worth it to me in that aspect. On my own time, taking hours and hours of prep work, welding time, then re-undercoating but not having to pay someone else seems pretty awesome.

burnsey

I have already come across seam Vs stitch welding on these forums somewhere, if I find it again I will post it here. From what I read stitch welding is preferred as if the weld forms a crack it doesn't spread across the full seam as it would if seam welded. But I am no expert in the area so don't know the exact answer, the person who is welding my cage as offered to teach me how to stitch/seam weld free of charge, so before I jump into it I just wanna make sure im not going to ruin the car by making it too stiff and also where to weld and where not to weld.

DavidNJ

This might help: http://www.millerwelds.com/resources...nd-chassis-fab

It was discussed here once...but not very much: https://www.s2ki.com/s2000/topic/822...-seam-welding/

Avoiding Weld Distortion on Thin Sheet http://weldingdesign.com/welding-qa/...thin-sheet-070

For those browsing the thread the descriptions and pictures here may be helpful in understanding the topic: http://www.vista-industrial.com/blog...-seam-welding/

I haven't welded in years and was never certified although I took some courses and read a lot. My steel bodied "Street Stock" at the time needed near weekly welding of something, usually making new bumper bars or brackets to hold the body panels.

It was my understanding that stitch welding was used in production applications to reduce costs and in other applications to reduce distortion. One technique was to make multiple passes of stitch welds, each pass filling the gaps between stitches until it became a seam weld.

I'd love to see the article that used stitched welding to limit crack propagation. While their may be no initial crack, the stresses would be higher on the second stitch. The crack implies a failure from an inadequate design or poor weld. Is there any cases where the crack is an intended failure mode?

DavidNJ

Andrew Wojteczko discusses his chassis prep in this article. He also has a long build thread: https://www.s2ki.com/s2000/topic/673555-unlimited-class-s2k-build/page__hl__casc. I think he sold it after a few test days but without actually racing it.



http://www.superstre...000-honda-s2000

As this picture from the article shows, he did a lot of stitch welding. It would be interesting to contact him and ash why.