Smelting alloy question

[jeff100]

Happy new years everyone. I am new to boolit casting, never done this before. I've been studying it for some time now, especially on this site. Also study the Lyman CB handbook 3rd ed.. I have a question about how to alloy lead.

I have purchased some scrap lead sash weights to use for casting boolits. Wheel weights are no longer available in Washington state. It appears to be very soft lead, I can easily scratch the surface with my fingernail. After I smelt it down, I'm planning to add tin and antimony to create a harder alloy for my big bore rifles? I was planning to buy some tin and antimony from Rotometals, the tin in short cut wire shape and the antimony in shot form. I'm worried about the antimony, will using pure antimony shot be difficult to get it to alloy with the lead? I notice that the melt point for pure antimony is quite a bit higher than normal smelting temps. I'm wondering if I would be better off to forget the separate tin and antimony and use something like solder or linotype to increase the hardness of my lead alloy? Any help would really be appreciated to get me started on the right path. Thanks. Jeff

[onesonek]

Well,,,,,I know lead and or lead/tin lowers the melting temp of antimony. How it acts or what temp is needed when introduced to molten lead, I don't know. I'm sure someone with that knowledge will chim in.
I just figured what I'm using for an alloy, that if I started with pure lead, that the pure antimony shot would cost me 40 cent per lb. of alloy. Providing I bought the Sb shot in enough quanity to not have shipping charges. Then you have to add the Sn cost, of which is twice the cost of Sb. But I would use 1/2 as much, so again the cost is 40 cents. (dang, I hope my math is right, it's early and only on the second cup of coffee,,,lol) I would have to get my pure lead for around 33 cents to match what I'm doing.
I'm buying WW ingot from "the Captain here, as well as Iso lead from Muddy Creek Sam. Then I have a source for used/salvaged Linotype from elsewhere. Problem with used lino. one never knows how much depletion it has gone through. So far what I have gotten has been good enough with an avgerage cost $1.37. My alloy cost runs right around $1.13 /lb. (avg)
I know that got slightly off track of your question,,,just making note, I think there is less costly ways to achieve your wants. Of course that depends on what you got your sash weights for. Esentially though, if you can find a reasonable source for linoype, it may be your least costly way. 1 lino to 3 pure lead will give about what WW's are. The you can water quench them or heat treat them if you want harder boolits. Or mix 1 to 1 and have roughly a 6-2 "hardball". Roto's "superhard" might be another route, but I didn't figure the what my alloy cost would be with that.

[white eagle]

rotometals make a product called super hard
you could alloy that with your soft
I do believe that it has all the antimony and tin you will need

[WHITETAIL]

You can always try Magnum Bird shot to add to your lead.

[lwknight]

Antimony shot is a lot more trouble to deal with than its worth. You can buy the superhard and actually get the antimony cheaper than in shot form if you count the balance of lead being worth about $1.00 per pound.

[Bloodman14]

As I understand, the antimony will dissolve slowly in lead, much like a piece of hard candy will in a persons mouth. Whether it is worth it to buy pure metals and alloy your own is something only you can figure out; I use WW's when I can get them, and scrap range lead, carefully separated into soft/alloy.

[lwknight]

I just found some 95/5 solder for $6.13 per 1/2 pound. The 1 pound rolls are $15.95 so the 1/2s are a lot cheaper
Lead free solder

I have bought from these people before with no problems.

[runfiverun]

i think i'd buy the super hard alloy and use that.
you at least would have a repeatable alloy.
if you mix lino and pure 3 parts to one you end up with @ ww alloy with 1% tin, a good alloy.
you can mix antimony ore into lead alloys but it is time consuming with a lot of stirring and fluxing..

[montana_charlie]

You can use home casting equipment to get antimony alloyed with your soft lead, but I think it takes a special flux.
There used to be information on that subject here...
http://www.theantimonyman.com/

EDIT...
It looks like he has quit selling straight antimony...and the flux needed to alloy it with lead.

CM

[onesonek]

i think i'd buy the super hard alloy and use that.
you at least would have a repeatable alloy.
if you mix lino and pure 3 parts to one you end up with @ ww alloy with 1% tin, a good alloy.
you can mix antimony ore into lead alloys but it is time consuming with a lot of stirring and fluxing..

Opps, I made a correction to my above post to 3:1 ( knew that but typed 2:1 ww/lino).

I totally agree that you would get a repeatable alloy with Roto's SH.
It looks like that would be 30 cents per lb. to get to a WW mix, not counting shipping and tin cost,,,,,,if my calculator didnt screw up

[Von Gruff]

You are lucky to get sash weight that are lead. All the weights I have seen in New Zealand are cast iron.

Von Gruff.

[Matt_G]

Good advice above about the Super Hard. If you have access to lino, that would work too.

This article will probably come in handy.
Alloying with SuperHard

[fredj338]

Antimony shot is a lot more trouble to deal with than its worth. You can buy the superhard and actually get the antimony cheaper than in shot form if you count the balance of lead being worth about $1.00 per pound.

I agree, getting antimony to melt & blend w/ your other metals is tougher than just buying an alloy & using that to tweek your alloy. Linotype ot monotype works great for alloying pure lead.

[rob45]

The best advice has already been given- obtain some typemetal or get Rotometal's "superhard" alloy.

For purposes of economy, the purchase of pure antimony should be considered only when already-alloyed sources are unavailable.
Or if you absolutely "have to know" what's in your alloy. Considering the fact that your base metal composition is not 100% certain (scrap sash weights), you are not operating under precise parameters to begin with, so this would not apply.


Do this stuff long enough and eventually you may run across a deal on pure antimony so good you can't pass it up. Or maybe you decide that you have a need for a more "precise" alloy. Or maybe you just get bored.
Whatever the reason, know that it can be done at home. Alloying raw antimony with lead does not require high heat; it requires patience and basic knowledge of the process.

Antimony tends to combine with other elements much easier than with lead. This includes oxygen, so best results are obtained by having an oxygen barrier. It also means that pure antimony will alloy more readily with an alloy that already has tin or antimony in it.
The home caster will obtain best results using crushed charcoal or kitty litter (bentonite clay) to inhibit oxide formation. A more elaborate setup would use argon gas.

Doing it this way produces perfectly acceptable results, but takes time. A specialized flux can be used to considerably speed things up. But the LETS flux is very difficult to obtain in small quantities, and it is not only extremely toxic, but also very corrosive.
These are but a few of the reasons why Bill Ferguson no longer offers it. For that matter, antimony itself is very toxic, and it would not surprise me that offering both antimony and the specialized flux present unique liabilities.

This subject comes up occasionally. Here are some references:
http://castboolits.gunloads.com/showthread.php?t=65747
http://castboolits.gunloads.com/show...alloy+antimony
http://castboolits.gunloads.com/showthread.php?t=66147


All said, you're probably better served by using an alloy with antimony already in it. Various typemetals or the 30% superhard.

Good luck,
Rob