Question about lead and antimony?

[RLW]

I understand that melting antimony into lead can be difficult. What I am wondering is if you had say 20lbs of pure lead and 20lbs of lead with 6% antimony and you melted them together would you have 40lbs of lead with 3% antimony and would it be evenly distributed enough? Possibly a stupid question, but something I was wondering.

[JSnover]

You are correct and distribution would not be an issue, especially if your pot is big enough to melt it all at once.

[sqlbullet]

First thing you need to understand to clarify this...Antimony does not melt into lead. It dissolves.

Think salt and water. We don't heat the salt until it is liquid and then stir it into water. The salt is dissolved into the water.

Same thing here. The melting point of antimony is 1167° F. They is theoretically achievable over a propane flame, but not terribly practical.

Luckily, the melting point of lead/antimony alloys are much lower. A 94/6 lead antimony alloy will melt about 600°F. If pure lead is added, all you need to do is stir thoroughly and wait about 10 minutes and the distribution will be even.

[Mitch]

sqlbullet describes it very well.

RLW you may be thinking of melting pure Antimony into lead this is difficult.But using Antimony rich alloy such your 6% alloy is very easy being the alloying of the Antimony has been done.This why rotometals sells super hard with a 30% Antimony content.Just do the math and melt and mix.

Bob

[RLW]

Great info. Thanks for the reply's.

[LAGS]

It takes an Hour and a Half to dissolve Antimony Crystals into Pure Lead.
I have the time and materials so I do it and make up mostly Linotype and Monotype for an alloy that is easier to smelt into a softer alloy that I use like a 1-3 blend.
I made up some Super hard with the 30 % Antimony, but it took forever for the Antimony Crystals to Dissolve.
Once you get past 20 % antimony to lead, it starts to dissolve way slower.
I think the Maximum Solubility of Antimony into lead is at 19%.
It will dissolve in eventually, but you have to start cranking up the heat to get it working.
Then you are near or even past the temperature that lead starts to Vaporize, causing Harmful fumes.
But once the 70 /30 blend is acheaved, it will melt at normal casting temperatures to blend with more lead or Tin to make the Mix you want to.
IMO, if you want to mess with a 70/30 ratio, then Just buy Rotometals Superhard, and save yourself a lot of trouble.