The difficulty with welding pot metal is probably determining what kind of alloy it is. It's probably mostly zinc or aluminum. You don't want to be welding zinc; it will release toxic fumes. And the aluminum alloy may be unweldable. Don't know about solder... or brazing... again, the type of alloy will be the problem there. And there's a chance you could wind up melting the piece to an unrecognizable lump before the solder or braze melted.

If the stress on the piece is not excessive, JB Weld might work. You could try reinforcing the back side with some extra metal (steel) and holding it in place with JB Weld. JB Weld is a high strength epoxy. Make sure the piece is very clean and oil/grease free first. Some brake cleaner (acetone) should handle that ok.

You can't braze or solder any type of aluminum.
I would first try the JB weld or any other epoxy you find that is for aluminum. Try a boat shop.

I'd want to see the foot- in a lot of cases, a bit like that will want a sprue- not hard to do, I use hanger wire clipped to size and ground smooth. but if the break is on a curve, or had a bend in it, it gets much trickier...

how big is it, and how much weight will it need to carry?

If this is a nice piece and you really want to save it you can get the right stuff for the job here.

http://www.muggyweld.com/potmetal.html

They even have videos showing how easy it is.

Here is a link that might be useful: muggyweld

My profession is pot metal repair, modification and fabrication of all pot metal parts. If you need a pot metal part repaired, please feel free to send me a description and photos of your part(s) via my website at https://potmetal.repair or text message to 7076215052. I will be happy to help you with your pot metal repair

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