When I built my CMC I decided to use stainless steel nuts and bolts.
I pretty much ignored the warning at the hardware saying to use anti-seize.
Galling can happen causing the nut to seize on the bolt.
I just had to cut off one of my front seat mounting bolts and yesterday spent about 8 hours getting a nut off one of my rear seat mounting bolts.
Earlier I had to cut off one of the front body mount bolts on top of the front torsion tubes.
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Thanks for that advice, Mike. You would have thought that stainless would be the way to go --I certainty had no idea about galling. I guess you takes yer pick---rust or galling!
Thanks for this good advice.
The galling won't be a problem if you use anti-seize.
Mike,
I feel your pain and have made the same mistake in the past. Anti-seize will definitely help, however I typically use a zinc plated Nyloc nut on stainless bolts. A major concern with stainless is the strength of the fastener. Many commercial stainless steel fasteners are very soft and will twist off or shear easily. For this reason I do not use stainless fasteners in highly stressed applications. However, I do use stainless in a lot of places because of appearance and corrosion resistance.
Also, you can polish stainless to where it looks almost like chrome! 
James
I did not realize there was a strength issue with SS.
Like James, I use stainless hardware where it makes sense... but never when it REALLY matters in terms of strength.
We tend to overdo it on the corrosion resistant hardware, in an effort to do it "nice". Very, very few of us use these cars in a way that they will ever see inclement weather, and the average Grade 8 fastener could probably stay submersed in water for a year before it started corroding. I only wash mine about 1x/yr. The rest of the time I use a waterless cleaner (Captain Richard's Best, or the like).
Michael McKelvey posted:The galling won't be a problem if you use anti-seize.
Hope this link works: I didn't know SS fasteners were that succeptible to galling.
I found the information in David's link very interesting. In all the cases where I had problems, I had used a nylock nut. I didn't know they were more susceptible to galling.
Stan Galat posted:Like James, I use stainless hardware where it makes sense... but never when it REALLY matters in terms of strength.
So Stan....stainless for corrosion resistance but not strength ? Wow. I always thought stainless was more or less for both but I'm sure no nut and bolt expert by far. Is it that stainless is hard but not strong or something ? I've tried to drill through it and it can be a bugger so I probably assumed that it meant ss hardware is strong. Thanks...
I avoided using stainless for things like suspension and steering
Because of the alloying elements which give stainless steel is corrosion resistance, it is not as strong as many steels. Stainless has a lower carbon content and is similar in strength to a grade 2 fastener. Grade 5 and 8 fasteners are a higher carbon, heat treated steel that give you much better mechanical properties.
Also, the chromium in stainless steel makes it work harden easily. This is why it is so difficult to machine or drill. Stainless has the odd properties of being “tough” but not very strong. The alloying elements also cause stainless to be “sticky”, thus causing the galling problem. Stainless steel tends to “stick” to itself easily.
James
Thanks for that info... It's been a long time since grade 8 
Having worked with a lot of stainless fasteners, my past experience tells me that when you install the nut and it doesn't go on smoothly through the nut...stop right there. you probably have a misfit on either the bolt or the nut and galling to the point of twisting off the bolt will occur. That's in either direction at that point. Find out which part is defective...nut or bolt and replace and discard the offender. Stainless is not a strong fastener so consider that as others on here have said. That's keeping in mind that we tend to over do it in the application of fasteners...Really think about what your application is.............Bruce
Yeah, suspension, seat belts,engine/trans mounts, and steering I use grade 8.
Bolting an oil cooler to the frame? SS. I have lots of SS 1/4-20 and 10-32 fasteners. Luckily, my grandfather worked at a SS fabrication shop in the 60s. I have coffee cans full of various lengths and threads, all in stainless. So a fair amount has made it into the car.......
Using a fair bit of stainless hardware in the Spyder build. I knew about the strength issues already, but the stickiness issue is news to me. Many of my stainless fasteners are going into aluminum thread inserts so I'll do more research (& break out the Neverseize).
I guess we've all learned a LOT from this thread - thanks to all who've added to it.
James wrote: "Stainless has the odd properties of being “tough” but not very strong."
I can vouch for that. I made a couple of driving light mounts out of 1/4" thick SS - MAN! That stuff is a B---- to work! Even heated the BeJezus out of it with a torch and it was STILL hard to work! Same thing with drilling it - really tough.
I grew to think of stainless steel bolts as almost brittle - stress them a bit with shear and they break much earlier than regular steel. I was not at all aware of the galling part so now I'm gonna rethink what gets installed where.
Thanks, everyone!
got a stainless pool ladder-handrail
grabbed wrenches and started installing...got about 5 turns and whoops, no turny-no more...
read the instructions then...(like most guys)
..."use anti-seize on all nuts/bolts"...
Will: You need a tee-shirt like mine:
Gordon, I like it!
but...I had these made for my buddy/mechanic Jim Ansite for all his great work this past year on Whitecloud...and I kept a few for myself
Dwight Knowlton who wrote and illustrated the Little Silver Speedster designed them
I like the wrench on the badge!
I've been told that SS isn't very magnetic either. Not very helpful if you drop a nut into a hard to reach place.
One more note about stainless fasteners.... Don't put them into aluminum and use caution around magnesium as the electrolytic action can destroy the softer metals. Don't ask me how I know. ;-0
"One more note about stainless fasteners.... Don't put them into aluminum"
Dang I was going to use them to attach diamond plate aluminum floor pans in an old dune buggy I have! Guess I'll stick with 1/4" pop rivets. (Old picture - the chrome spoked wheels cleaned up nicely and new radial tires. It's a full pan 4 seater.)
Will Hesch posted:Gordon, I like it!
but...I had these made for my buddy/mechanic Jim Ansite for all his great work this past year on Whitecloud...and I kept a few for myself
Dwight Knowlton who wrote and illustrated the Little Silver Speedster designed them
Nice Will, I just had one made myself. ... 
IaM-Ray posted:Will Hesch posted:Gordon, I like it!
but...I had these made for my buddy/mechanic Jim Ansite for all his great work this past year on Whitecloud...and I kept a few for myself
Dwight Knowlton who wrote and illustrated the Little Silver Speedster designed them
Nice Will, I just had one made myself. ...
Nice...who made it for you, Ray ?
Wolfgang, that rear clip looks like the front of a VW Bus!
David vistaprint.ca. You upload your pict add text andchoose your shirt and colour
Voila
They embroider too but I wasn’t sure the IM logo would turn out nice and they only had kids size in golf shirt
men’s siZe is 3x
dang...
Safety Jim posted:One more note about stainless fasteners.... Don't put them into aluminum and use caution around magnesium as the electrolytic action can destroy the softer metals. Don't ask me how I know. ;-0
A little word of caution about never seize and anti seize...never use it when your using a torque wrench and tightening to a specific value. You may twist off your fastener before you reach your torque value. Always us the lubricant called for for the fastener. Sometimes they state No lubricant or dry. Wheel lug nuts are a common abuse of never seize......be careful.............Bruce
