How much to add?

[GARCIA]

Getting some 95% tin and 5% antimony solder from one of the board members. Being new to this endevor of casting and pretty darn poor in the math arena how much of this should I add to a 20lb pot?

I fully realize that my base metal is a deciding factor. I am only using a mix of 50% WW's and 50% sheet lead for one. The other is pure WW"s.

Really looking for a good sharp fill and a little more hardness.

Any help from the guru's of Galena is always appreciated!

Tom

[white eagle]

6.4 oz. if and that a big IF you want 2%

[bumpo628]

Here are the specs for your current alloys:
Pb/WW mix: 0.25% Tin, 1.01% Antimony, estimated hardness 10 Bhn
Clip on WW: 0.5% Tin, 2% Antimony, estimated hardness 10-12 Bhn

The tin is a little low on the 50/50 mix. You should add 2 oz of 50/50 solder per 20 lbs to bump up the Tin.
The new specs would be 0.56% Tin, 1.00% Antimony, estimated hardness 10 Bhn.

Mixing the 5% with pure lead
Regarding your new lead with the 5% Antimony, you might want to save that for mixing with pure lead and solder instead of your other two alloys.
In a 50/50 ratio, your specs would be:
0% Tin, 2.5% Antimony, estimated hardness 11
With 4 oz of 50/50 solder added:
0.62% Tin, 2.47% Antimony, estimated hardness 11

Mixing the 5% with your existing alloys:
If you mix the 5% alloy with WW in a 50/50 ratio, your specs will be:
0.25% Tin, 3.5% Antimony, estimated hardness 12
Adding 2 oz of 50/50 solder to the mix:
0.56% Tin, 3.48% Antimony, estimated hardness 12

If you mix the 5% alloy with the Pb/WW mix in a 50/50 ratio, your specs will be:
0.13% Tin, 3.01% Antimony, estimated hardness 11
With 2 oz of tin added:
0.44% Tin, 2.99% Antimony, estimated hardness 11.5

You can download my excel alloy calculator here:
http://castboolits.gunloads.com/showthread.php?t=105952
Be sure to get the 2/6/11 updated version with the hardness estimates.

[lwknight]

Garcia, if thats a 20# Lee pot it only holds 16 pounds running over full.

[GARCIA]

Yeap, Lee pot. Learn something new everyday.

O.K. since I admitted to not being a math wizard, just how much weight wise should i add to the 16lb mix?

White Eagle is saying around 6.4oz per pot.

bumpo628 is giving me all kinds of info plus a calculator.

Heck, I am going to really have to play with all this!

Thanks to all!!

Tom

[stubshaft]

Believe it or not it gets easier as you work with it. Keep good notes of your alloy mix so that when you find one for the boolit you are casting you can repeat it.

[bumpo628]

Yeap, Lee pot. Learn something new everyday.

O.K. since I admitted to not being a math wizard, just how much weight wise should i add to the 16lb mix?

White Eagle is saying around 6.4oz per pot.

bumpo628 is giving me all kinds of info plus a calculator.

Heck, I am going to really have to play with all this!

Thanks to all!!

Tom

16 is 20% less than 20, so reduce the weights of all the info I listed above by 20%.
Just play around with the calculator and print out recipes that you use. That will make record keeping easy and repeatable.

[Smoke-um if you got-um]

There was a post a while back........ claimed that adding 3" of the 95/5 wire solder per pound of alloy added 1% tin to that pound. I can't seem to find it right now but that is what I have in my notes here at the house.

Mike

[lwknight]

Actually about 15 pounds is the most that you can safely work with in the Lee 4-20

Anyway about 5 oz of tyhe 95-5 solder will fix you up nicely. It does not have to be precise. I like to aim for 2% tin but a lot of folks do just fine with 1% and up to 5% can't hurt you either.

[Matt_G]

...a lot of folks do just fine with 1% and up to 5% can't hurt you either.
True, but with the price of tin being what it is, 5% will sure hurt your wallet. [smilie=l: