About a year and a half ago I had a guy ask if I could weld repair his
favorite wheelchair. I told him to bring it by and I'd look at it. It
was some kind of mystery metal that was magnetic. I ended up tig
welding it with stainless because I've found SS would often make a
better repair than 70S2 when the iron alloy is unknown but not likely
to be tool steel. My policy on these types of repairs is to guarantee
my weld but not the edge of the HAZ and beyond. So, if the weld
breaks, or if the bead breaks out of the part, I fix it for free.
Forever. But if it breaks beyond the weld then it's tough beans. It's
hard to tell where the HAZ ends sometimes so I figure about .060"
beyond the bead is where the guarantee ends. Anyway, all this was
explained to the wheelchair owner and he said sure, weld it up. Then,
I get a call this morning from the guy. He asks if I remember the job
and I say yeah. He says it's still holding and thanks for the good job
done. Boy, did that make my day!
Eric R Snow,
E T Precision Machine