Am Samstag, 16. Mai 2020 17:49:37 UTC+2 schrieb :
On Thu, 14 May 2020 17:11:23 -0700 (PDT), Christopher Tidy
wrote:

Hi folks,

I have a 1/2 hp dual-shaft electric motor from 1937. It runs and I'm planning to add a couple of buffing mops for polishing metal. But it's missing part of a mounting foot. Here's a pictu

http://sphinx.mythic-beasts.com/~cdt...Motor_Foot.jpg

Do I stand a reasonable chance of repairing the foot using 2 mm stainless welding electrodes and an oil-cooled AC welding set?

I was thinking of grinding away a large, neat piece and making a mild steel slotted piece to match, and also bevelling the edges, but I can't really pre-heat the part.

Will this work? What do people think? Thanks!

Best wishes,

Chris
Greetings Chris,
You're in luck because the base unbolts from the motor, which makes a
repair much easier. If you can find your DC welder then Stoody
Castweld 55 will work to repair your motor base. The weld deposit is
hard so you would need to grind, rather than machine, any excess weld
off. I have used Castweld 55 to weld cast iron to steel as well as
cast iron to cast iron. It really does a good job. There are other 55%
nickel rods available that can be welded with AC but I have never used
them. You could also use NI 99 rod and it is softer, so the deposit
can be filed rather than ground. The nice thing about the Castweld 55
is that it won't shrink and cause cracking. In any case, since the
foot is removable, you should pop it in the oven at 350 or so degrees
F so that it is good and hot when you weld it. This will really help
to keep everything from cracking.
Cheers,
Eric

Thanks very much for the detailed advice, Eric. I was hoping to use the AC welder, but it sounds like the (big and heavy) DC machine might be better.

I was planning to grind out a square from the motor foot and make a piece of steel which fits into the gap and features the complete mounting slot. This way the welds will be longer, and hopefully stronger. I was also going to vee out the edges and hopefully complete the whole weld from the underside. Not sure if it would need one or two passes with a thin rod.

Chris