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moses
03-01-2012, 06:24 AM
I recently got some foundry type, OK it might be monotype, how do I know?

Anyway, when I was smelting it, it got real slushy and no matter how long I let it sit on the propane burner it still had some of this silver slushy looking stuff on top, so I fluxed with wax and it looked like the slush turned to a powdery looking dirt, I then scooped this stuff off and after fluxing again I poured the ingots.

I was concerned that this stuff might be antimony, then tonight I read this
http://www.lasc.us/CastBulletAlloy.htm
Below is the paragraph that concerns me.

"Lead/antimony alloy drosses considerably. As your melt reaches liquidus temperature that silvery, lumpy, oatmeal looking stuff floating on top is antimony. Skimming it off seriously depletes the alloy; it needs to be fluxed back into the melt."

I fluxed a few times trying to get this stuff to mix back in the alloy but it wasn't happening.

Is this stuff antimony or is it just **** that was in the foundry type?

BTW the ingots I poured are very very hard so I know there is antimony in them.
I tried to put a mark on the ingots with my finger nail and it doesn't even come close to making a mark, or scratch.

I can take pics of what the stuff looks like if that will help, as I saved it.

Thanks for any help.
btroj
03-01-2012, 07:59 AM
That's the antimony alright. I have so monotype and it does the same thing.
I flux it heavily with sawdust. That and so more heat seems to do the trick for me. Firs few times I melted some imhad the same troubles.

And a good amount of sawdust and let it sit and char. Once it has started to char and you know it has the moisture driven out of it I start stirring . This is when the slush starts going away. It may take a few flux cycles to totally get the slush mixed in.

I have never melted just monotype to make ingots. I like the little blocks, they are easy to deal with and are pretty clean already.
imashooter2
03-01-2012, 08:01 AM
Reducing the slush to powder means you fluxed correctly. Your alloy and ingots are fine.
bumpo628
03-01-2012, 12:11 PM
Next time just leave monotype/foundrytype in raw form. Weigh and add to your alloy as needed.
mpmarty
03-01-2012, 06:30 PM
I too use monotype in my casting. I never smelt it but add it to molten wheel weights and flux it in with sawdust. No crud on the surface at all.
Charlie Two Tracks
03-01-2012, 07:54 PM
I turned 50lbs of Foundry type into ingots last year and I wish I had not done that. It is much easier to use if left in its original form. A 5 lb. ingot of Foundry type will do some serious hardening. Live and learn.
moses
03-01-2012, 08:45 PM
My ingots are 2lbs, I figured one 2lb monotype ingot with 18 lbs of range lead would make for a good alloy for 9mm boolits. Is that not a good ratio?

Imashooter2, so what is the powder that is left after I fluxed the slushy antimony?



thanks
btroj
03-01-2012, 08:58 PM
That should be a reasonable alloy. If it is too soft you could add another pound of the monotype. Even then it won't be much harder than wheel weights.
imashooter2
03-01-2012, 09:10 PM
My ingots are 2lbs, I figured one 2lb monotype ingot with 18 lbs of range lead would make for a good alloy for 9mm boolits. Is that not a good ratio?

Imashooter2, so what is the powder that is left after I fluxed the slushy antimony?



thanks

Dirt, burnt ink... could have been anything.
runfiverun
03-01-2012, 09:39 PM
i don't know what the powder is but if you squeeze it against the side of the pot it will keep on giving up little silver beads.
i finally just toss it.
bumpo628
03-01-2012, 11:15 PM
My ingots are 2lbs, I figured one 2lb monotype ingot with 18 lbs of range lead would make for a good alloy for 9mm boolits. Is that not a good ratio?

That will get you in the neighborhood of 1% tin, 2.5 to 3% antimony.
Sounds good to me.
runfiverun
03-02-2012, 01:00 AM
My ingots are 2lbs, I figured one 2lb monotype ingot with 18 lbs of range lead would make for a good alloy for 9mm boolits. Is that not a good ratio?
thanks

range scrap is often harder than ww's are.
you have a complete unknown there and it can change from batch to batch.
you need to make as large of a batch of the range scrap as possible.
then have a way to check it's hardness after 10 days or thereabouts.
you then have an idea of it's bhn.
adding monotype to a bunch of lazercast/commercial cast boolits and some other stuff would be counter productive.
pick a hardness say 12 bhn then only add the hard or some soft to keep things close to that hardness.
at least each batch will be somewhat close in makeup.
imashooter2
03-02-2012, 07:51 AM
Sound advice from runfiverun.