Foundry metal?

[fatelk]

I have a few pounds of this metal, that I got from an old timer at a gun show a few years ago. He called it foundry metal, and there was a label in with it. It's very hard and brittle.

My question is, what temperature should this stuff melt? I tried to mix some in a pot of lead and it didn't seem to want to melt. I didn't let it get real hot just in case it had some zinc or something.

The torn-up tag indicates 13% tin, 25% antimony, and 62% lead, but I have no way of knowing how real that is.

72277

[btroj]

Hard and brittle would be right. May take some serious fluxing to get it totally mixed in. Don't scrape off the lumpy dross, it is the good stuff. Flux that stuff in!

[Lloyd Smale]

Id be skeptical for two reasons. First foundry metal should be easier to melt then pure lead or wheel weights and secondly the ingots you show look so rough. Most linotype or foundry metal casts so nice id expect better looking ingots. As course as that looks inside the broken ingot id make a guess that maybe what you have is antimony or possible zinc.

[Hickory]

It's probably real from the picture.
The "lead" shows crystallization where it has been broken.
Sure sign of high antimony.

[fatelk]

Thanks guys. It's the melting point that has me concerned. I had the pot of lead at maybe 700 degrees or a little less, dipped an ingot in and it showed no signs of even starting to melt.

[dbosman]

In my very tiny experience with foundry metal, it didn't melt until it all melted. It was solid and then it wasn't there.

[fatelk]

ZINC. It's a bunch of dang zinc, 10 lbs. I emptied my pot, then threw it in and left it to heat. I forgot for a while, then came back to find a bunch of nasty, overheated mush. It was all my Lee pot would do to melt it, and I had a heck of a time getting it out. There is still a bunch of hardened deposits stuck to the bottom and sides. I'll have to see if I can chisel them off tomorrow.

I'll bet the old guy I bought this stuff from melted down a bunch of zinc and didn't know what it was, so he looked up what he thought it was and wrote down the percentages he found. I don't know what else it could be and I have fiddled with melting a little zinc before. As I recall he had a whole bunch more. I'm sure glad I didn't buy more than what I did. :(

[SciFiJim]

Before you toss it, test it with muratic acid (swimming pool acid). If it bubbles, it is zinc.

[Indio]

You sure its zinc?

I cast some foundry type in my lee 4-20 pot recently for a mate doing some experiments... I normally run the pot on a 4-5 heat setting for magnum/taracorp alloys and can add small amounts as I cast and still get a good pour .. The foundry type needed forever to melt (it looked like a metal slushy for ages), the pot need to be running flat out (10) and any air movement around the pot and it stopped pouring (had to close the doors and windows), any adding new metal and it stopped pouring.

[Lloyd Smale]

any foundry or linotype ive ever had melted eaisly. It does go from solid to liquid in on step but i never got a bunch od slush or had to use high temps. Id do just what you did and toss it!