I have a collection of large and small ball bearings that I want to make into forming stakes by welding into a mild steel stem. I am thinking of using either 7018 or SS 309. Please advise.

Thank you

I would use the stainless. If you can find some "Hi-Alloy 500" that would be awesome. I have welded B-7 stud bolts to bearing races (in order to remove races) with no failures. Most impressive rod and runs like stainless.

I tend to lean twords using stainless also, but I would personally go with ER308L if you have any handy.

I agree that the stainless is probably going to be the best. I believe you can also weld it with 7018, but I would preheat the brg to 350.

Definitely pre-heat and postheat ballbearings, often 52100 and prone to HAZ issues.

Thx for the advice. I do have some 308L which I picked up very cheaply. And yes, I definitely plan to preheat.

I hate to keep asking but doesn anyone have a good method for putting a collar around the 1" stem so it sits on the hardy? I was thinking of notching 3/8" bar at one inch intervals, welding it on to the stem and welding in the corners to fill them.

Thank you.

I'd go with 309L stainless rod or wire for dissimilar steels. I've found some ball bearings will weld very easily and others not at all. Not sure what the difference was as they were unidentified scrap bearings.