Lead - Antimony alloy

[GeorgeGreek]

Hi people,

I'm perhaps the newest member (though 67) of the forum.
My question : Has anyone tried to make such an alloy and how ?
I have the antimony already and hate to waste it.

George

[trk]

George -

How much depends on how hard you want your alloy.

Lots of folks don't use any, keeping to a 20:1 or 30:1 lead-tin alloy.

Others use wheel weights, which generally have 3 to 4 % antimony, the rest lead.
They're moderately hard air cooled out of the mould, and right-much hard when dropped into water right out of the mould.

[imashooter2]

Back in the day, I acquired a 5 pound lump of antimony from a local metals supplier. I built a charcoal blast furnace from firebrick and a shop vac to achieve the over 1,167 degrees required to melt it. I placed the antimony and 5 pounds of lead in a heavy cast iron crucible and put a thick layer of powdered charcoal over the surface of the raw material. The end result was a 50/50 mix with lead that would then melt at normal casting pot temperatures. It was an enormous PITA. I'd never do it again. Type metal is too cheap and available.

I've heard that the theantimonyman.com will provide finely powdered antimony and a special flux that will alloy it to lead at low temperature. I've never tried it, but it seems to be very process sensitive.

[Ricochet]

It should dissolve in molten lead at temperatures well below antimony's melting point, but it might take a long time. I haven't tried it.

[Bass Ackward]

try this from the Antimony Man.

ANTIMONY
The product looks like small metal gravel. It is quite pure with dust and fines removed.
ALLOYING FLUX
The flux is a pink powder which absorbs moisture so it must be stored in a sealed container with a desiccant such as silica gel when not in use. It has a MAXIMUM alloying temperature limit of 635F. The lowest temperature is that where the metal to be alloyed, LEAD, or LEAD/TIN or TIN is completely liquid. These temperatures range from 621F for pure lead to 450F for pure tin. 93/7 tin/antimony pewter is made at 500F.

PROCEDURE
1. Start with a clean pot and clean metal or alloy. Bring up to operating temperature, minimums as given above.
2. Spread a very light film of flux over the melt surface and let it melt. The simplest applicator is a 'salt shaker' type container. Letting it melt insures evaporation of any adsorbed moisture.
3. Sprinkle on a light coat of granulated antimony. Follow with another thin film of flux. When the flux has melted the antimony will have warmed up enough to not 'chill' the melt.
4. Start stirring slowly and smoothly. The antimony and flux float so there is no advantage to agitation. Stirring rolls the antimony particles over in the film of flux on the surface of the melt. EXCESS FLUX is indicated by a dark foam or crust. As the antimony is encased in this flux it will not contact the melt and solution slows and stops.
5. Learn the lesson, skim off all foam, antimony and excess flux. When cool, wash with water, the flux and flux products dissolve leaving the antimony. Dry it.
6.Start over again and control flux properly. As the antimony goes into solution, add very thin film of minimum flux when reaction appears to have stopped and continue stirring.
7. Eight to ten minutes is usually adequate time to make linotype " IF " the procedure is followed properly. As with any process it takes practice to maintain proper temperature (as low as possible), add minimum flux and spread antimony in the proper amounts.

Ahhhhh, you do have a thermometer don't you? :grin:

[38 Super Auto]

Richochet is right. Antimony will alloy with lead below it's 1200ish degree F melting point. It does take awhile. I usually all the Sb early in the smelting process to give it time to alloy into the melt. It seems to do better if I can keep it submerged.

A casting buddy and I did a buy on some antimony a few years ago. I add ~2% Sb chunks and 1% Sn to WW lead for high velocity bullets (1300+fps) With water drop out of the mold, I get some dandy bullets.. Otherwise, I use WW for .45ACP and .38 spec.

Sn will improve fill and shinyness - we like good lookin' bullets, right? I think tin's beneficial effect on hardness at higher concentrations is small, so go easy on the solder.

I'm a scrounger and try to base my boolits on WW or range lead, but my scrap metal dealer here in town sells lead for 65c/lb. They separate out the hard lead, which is usually some kind of type metal or bar solder. It's pretty sweet to get solder at 65c with tin over $7/lb and lead over $1.50/lb

It's a good option and it's local.

[GeorgeGreek]

Thank you all for useful info.
Agree that type metal is best and I want to make that alloy for other purposes than bullets (small model metal castings) but such is not available in Greece anymore...

Thanks again,

George

[testhop]

welcome george
if you cant use it now just wiiait soner or later you will get some soft lead and then you can
mix up some good mix of course you will need some tin

[John Boy]

George, give this alloy calculator program a try to mix your antimony and lead to a specific ratio