stainless for frame

[outkasted]

Hey, new to the forum here, looks like a pretty cool place.. anyway,, got a quick question, building a stainless frame for my '30 chev 3 window coupe, any suggestions as to the type I should be using, I was thinking 304, but if any body knows any better, please tell me

[hotrod396]

How cool would that be?
I just finish a bike build that i used a ton of SS on. Do you know what your getting yourself into? anyway you look at it $$$$

Sorry i didn't help U any

[C9x]

Talk to a professional welder.

I've read several quotes lately that indicate stainless is easier to weld than mild steel and way easier than aluminum.

You can weld mild steel to stainless, but I wouldn't do it in critical areas.

The stainless you need may only be available in one grade.


Short story here:
A few years back I was going to build an 8' wide x 5' tall wrought iron gate.
I went to a steel place where I'd purchases aluminum and stainless - thinking they also carried mild steel.
I asked for 1" square tubing, 1" x 2" rectangular tubing for the gate and 2" square tubing for the posts.

I said mild steel a couple of times right up front and the guy said ok.

I figured it was gonna cost around a hundred bucks or less - steel prices were within reason at the time.
The bill was $437.
I about fell over and when I looked out the window I saw the warehouse guy wrapping some stainless with plastic.

I was a bit surprised to learn that stainless was available in square and rect tubing sizes so you should be able to find what you need for your frame.

You may want to do some research.
Some stainless grades may not have the fatigue life that mild steel does.

And keep in mind, the little accessory pieces that require threading for mounting things as well as the crush tubes will have to be stainless.

In any event, it should turn out to be and interesting and good looking frame.

[outkasted]

I thought it should be pretty cool, I got no problem welding stainless but didn't know if 304 would stand up or if I needed to go to with something else

[Big Tracks]

Well, good luck, outcasted.

Some months back I mentioned the fact that I'm not a welder and I CAN PROVE IT! And I'm not getting any better at it. As C9 said (and also according to my welder brother) it's easier to handle than mild steel.

With a former employer I had occasion to work with stainless quite a bit and I know from experience that making small parts, particularly in your home shop and using hand tools that work fine on other metals, can prove real interesting. I guess what I'm saying is, don't plan to pick up your trusty hand shears and a file when you start fabricating smaller pieces.

Stainless bolts have an annoying way of binding up when you screw on the nuts. The tendency is to keep tightening until the nut won't go either way. Then you're faced with getting that sucker out ...... somehow.

As C9 suggested, call in the pros.

Again, good luck.

Jim

[C9x]

I forgot to mention that stainless bolts & nius - as Big Tracks points out - tend to gall and after awhile stick together and upon removal the bolt or stud shears.

The usual stainless bolt you buy - 308 & 316 - is about equal to grade 4.

ARP has stainless bolts that are rated higher than good ol grade 8 so I'd make a point to use those.

Along those same lines, use Never-Seize on stainless bolts & nuts - even with nylocks.

I had the integral stud from a Deuce Factory stainless lower shock mount seize the nut and shear off.
That was a fun project to set up in the lathe for drilling and tapping for a replacement stud.
The shock mount was repairable and too darned expensive to throw away.

I use Never-Seize on the nylock shock nuts and have never had a problem with them loosening.

I'm pretty sure the galling is a mechanical thing that probably starts at the microscopic level.
Along with that electrolysis can rear it's ugly head which can lock nuts & bolts together.
Especially when a stainless bolt is used in threaded aluminum.

[Henry Rifle]

Thread galling seems to be the most prevalent with fasteners made of stainless steel, aluminum, titanium, and other alloys which self-generate an oxide surface film for corrosion protection. During fastener tightening, as pressure builds between the contacting and sliding thread surfaces, protective oxides are broken, possibly wiped off, and interface metal high points shear or lock together. This cumulative clogging-shearing-locking action causes increasing adhesion. In the extreme, galling leads to seizing - the actual freezing together of the threads. If tightening is continued, the fastener can be twisted off or its threads ripped out.

[Ed Rodder]

another issue is that cutting and drilling is a whole lot harder on your bits and tools. Its a blast to tig weld and can look real nice.

[outkasted]

thanks guys

[hotrod396]

For a good grade of bolts & nuts ARP they may cost more but there a hell of lot better then ace hardware.

[gwaidman]

304 will be fine and will likely be the most common available. I see no reason to go up to 316 as strengths are similair, but 316 offers additional corrosion resistance and additional cost to an already expensive metal. I trust the frame will be a beauty when its done. Good luck.