Is it possible to remove tin, etc. from lead?

[35 Whelen]

So I'm trying to get some pure lead to use as the basis for some 20-1 or 25-1 alloy. I have some think sheet lead that was used around telephone cables. When I smelt this lead, is there some procedure by which I can remove all traces of any other metals?

Thanks,
35W

[mpbarry1]

It might be, but i would think your local salvage yard would have roof flashing for 40 cents a pound. best soft lead you can find! any impurities would be minimal!

[runfiverun]

the foundry's use zinc to strip tin from recycled alloys.
you pour the melted alloy into a thin waterfall like sheet then shoot the melted zinc through this sheet of alloy. [it grabs the tin on it's way through]
it seems like a lot of work to me to build all that equipment and don all that gear to clean 30-40 pounds of alloy though.

[lightman]

That phone cable sheathing should be 98% plus pure. The seams are soldered, so you will have a little tin in the mix, unless you cut them out. Is that not close enough for what you have planned? I have a lot of that stuff and it test out to have a hardness of 5 or 6.

Some of mine was heavily oxidized and had tape all over it, but melted out to be very soft. Lightman

[Smoke4320]

just another to chime in .. your phone sheathing SHOULD be very close to pure ..I would melt it, flux with cedar or pine sawdust and pour.
the minor tin from the solder joints will only help the mold fill out and will not be enough to affect say a muzzleloader bullet .. YMMV

[Defcon-One]

Why do that? If you want to ad more Tin to it anyway.

20-1 and 25-1 are binary Lead/Tin alloys. Just melt all your soft lead into one big pot so it will all be the same exact mix, then pour ingots.

Use any method available to find the actual Tin content and add enough Tin to it to get to your desired percentage.

20-1 is 4.76% Tin
25-1 is 3.85% Tin (This makes great Hollow Point Bullets!)

If you can't get it tested, then make a good guess based on hardness, etc.

Or, if you have any known Pure Lead (I meant like one ounce or less!) you can pour just one bullet from that (say a .45 cal 230 gr.), then use the same exact mold and pour one from your binary Lead/Tin alloy. The weight difference will tell you how much Tin is in your unknown alloy. I can provide you an example of the math later, via PM, if I need to. It is base on mass per unit volume. Just gotta find it in my files.

[35 Whelen]

I want to start with pure lead so I can end up with an exact alloy; either 25-1 or 30-1, probably the former. I'm looking for bullets in the 9.0 - 9.5 BHn range.

If I had a way to test my lead, this little project would be a no-brainer. If I had known pure lead, again, no-brainer. To do it based on hardness, I have smelt the lead, pour it into ingots, wait for it to harden, etc. etc. I much rAther spend time shooting than casting!

I recently the Fryxel write up on why alloys need to be fluxed and how tin seperates from the alloy through oxidization. That being the case, sounds like a fella could melt his lead, NOT flux it and over time the tin would float to the top. Or am I oversimplifying it?

35W

[mold maker]

Just like a mixed drink, once mixed, it's beyond most of our equipment and knowledge to separate it.
If it casts well, and is about the hardness you feel you need, just use it.

[Bullshop]

I have pure soft lead from x-ray sheeting. I will tarde at 1.5 to 1

[bangerjim]

Using sulfur will remove pretty much all tin and antimony and zinc in your smelting pot. Horrid smell, but it does seem to work. Get it at plant supply stores.

Copper sulfate will do it also with less smoke/smell, but is has been written that it adds a bit of copper.

Get it as root killer in the plumbing section of your favorite big box.

banger

[boltaction308]

I read on another post here that using sulphur as a flux will remove zinc and tin.

[Defcon-One]

OK, then just do what I said and then melt one ingot, add some Tin and see where the hardness is. Keep adding Tin until you get in the 9.0 - 9.5 BHN range. Once you have a recipe, use it on the rest of the ingots as required.

Yes, you are simplifying it! You will not get the Tin back out without a refinery!


I went through this myself once, I wanted to make Lyman#2 (EXACTLY). So I got a ton of Large Core Isotope Lead, known to be 1% Tin, 3% Antimony and 96% Lead. I then got some factory bars of 50/50 Solder and some Linotype, known to be 4% Tin, 12% Antimony and 84% Lead.

I was all set. Everything going in was a known alloy so, I made 300 lbs. of Lyman #2 which should have been EXACTLY 5% Tin, 5% Antimony and 90% Lead. It wasn't!

I found out later via XRF that the Linotype was only 3.12% Tin, 10.23% Antimony and the rest Lead. The Isotope Lead was only 1.45% Antimony, the rest Lead and it had no Tin at all.

Know alloys aren't alway what you think they are, either! I have proved it in my casting more than once.

Even the XRF units are not perfect and introduce some error or lack of repeatability.

DC-1

[fryboy]

if you really wish to remove some tin ...heat a smelting pot full up to around 800-850 F , let it sit , tin will oxidize out ,when there's a heavy layer carefully skim it off ,once skimmed stir the pot real good ( no flux ) and let it sit again until you have a heavy layer on top , repeat as many times as desired , it's slow , it's hot and it sucks and while it will not remove antimony nor all the tin it will remove a fair amount , patience is the key

[bangerjim]

I get the distinct feeling many are getting "lost down in the weeds" on this alloy % thing. It is NOT that critical to have 2.3455% of something in an alloy. 2-3% is a SWAG.....and darn close enough.

An x-ray gun will give different readings on the same metal......at two or three significant digits "in the weeds". Just like our hardness testers, readings are within a band of errors and should treated as such.

That is the way I do it and it works for me!


banger

[onomrbil]

Electrolysis works every time

[35 Whelen]

if you really wish to remove some tin ...heat a smelting pot full up to around 800-850 F , let it sit , tin will oxidize out ,when there's a heavy layer carefully skim it off ,once skimmed stir the pot real good ( no flux ) and let it sit again until you have a heavy layer on top , repeat as many times as desired , it's slow , it's hot and it sucks and while it will not remove antimony nor all the tin it will remove a fair amount , patience is the key

This is exactly what I did yesterday, then poured it into ingots. Waiting a day or two to check the Bhn.


I get the distinct feeling many are getting "lost down in the weeds" on this alloy % thing. It is NOT that critical to have 2.3455% of something in an alloy. 2-3% is a SWAG.....and darn close enough.

I normally pay little to no attention to hardness and alloy ratios, but I want to begin casting HP's for hunting and have a specific Bhn goal in mind and want as little antimony in the allow as possible so as to reduce the brittleness of the bullet.

35E

[fryboy]

while i do not use my current hp's for hunting i do like the addition of tin , unlike antimony tins adds much in the way of malleability , up to a point added tin also reduces antimony's brittleness , my hp alloy is currently 3 to 1 Pb/coww with around 2-3% tin added , it cast a lil small compared to ww's straight ( of course ) but out of a 45 acp the expansion is phenomenal !!
not sure how much you got out of yesterday's umm smelting procedure , i use a separate dross can for such instances and it goes back into a later smelt of ww's used for plain plinking , the heat and patience is what does it , tedious for true but as long as you're happy that's what counts , sadly even stick on ww's can be a mixed bag leaving me to suggest it is much easier and possibly cheaper to start with some scrap sot lead such as pipe or roof flashings to obtain a "desired" percentage
i've also noticed that while tin can and does harden a alloy somewhat that tin and most solder remain on the soft end of the hardness scale

[Texantothecore]

Electrolysis works every time

Can ypu expand on your comment?