Re: How do you tell if it\'s crome moly?
Lots of interesting stuff!
What I did:
It's just an ice chest rack, but it had to tee into the frame. I didn't want to weaken the frame there.
I took the rack's round legs, which were about 3/4" mild tube, teed them into a rounded mild steel section that conformed to the roundness of the frame, - which at that point was 1 1/4 CM tube. That "footing" was I think made from 1.5" tube - about 1/3 section. That gave it a footing to distribute the load, rather than just a tee type joint.
Then I welded that footing to the frame rail.
My friend brought home some gas rod he got from work he said they use on CM. I used oxy/acetelyne with a slightly carbonizing flame, heating the entire area several inches around it fairly hot - to a very dull red, then welded it. I made sure that there was no strain on the area - axle stands all around under it to prevent any bending or distortion.
I kept the torch playing on the surrounding area afterwards letting it all cool down slowly.
The actual welding was easy, I expected it to fight me but it flowed very nice. It almost felt like brass the way it flowed. I didn't use a lot of filler, trying to meld the two base metals together. The filler mostly went on top.
While I was doing it I saw 4 more cracks in the frame in the front - the TIG welds there were cracked along next to the weld. I used the oxy acet to fix those too, again pre-heating the entire surrounding area first, and cooling it very slowly.
I think one very important aspect was the pre and post heating. The TIG welds probably weren't preheated. To hot too fast, then too cold too fast caused the welds to break away from the base material.
The way it acted and felt I have a feeling it's stronger now than before. Time will tell, if it's breakable, he will. But then, since I get to run it sometimes, I probably will.
Thanks again for all the inputs - it has been very educational.
That's why we are here - to share info and help one another.
Thanks again, Rich