Sulfur rabbit hole

[triggerhappy243]

So, i want to run some questionable lead alloy i have from wheel weights and sulfur. I have a "65 pound" capacity melting pot. Could someone who has done this give me an idea of how much yellow sulfur i should put on top of the melt?

[poppy42]

First off have you tested it to determine that it actually contains zinc? That’s your first step. If you can put some pool acid on your cooled alloy and it doesn’t bubble there is absolutely no reason to treat it with sulfur! As far as the process, I’ve done it and it’s a process. Add some sulfur, mix it in, skim off the sludge, and repeat until the zinc stops binding with the sulfur and you no longer have a crust. Basically depends on how much zinc is in your alloy. When you can skim it and you no longer find any oatmeal floating on the top and it looks like clean lead alloy you’ve got the zinc out. It stinks! It’s time consuming! It’s a royal pain! But it works! It’s not something I would do for a small amount of contaminated alloy. It’s just not worth it. And it’s certainly not something I would do because I think maybe possibly there’s some zinc in my alloy. It is a last resort! That’s about all I can tell you about it I don’t know if there’s an actual way to determine the percentage of sulfur to use other than a lot!
Good luck!

[triggerhappy243]

first off have you tested it to determine that it actually contains zinc? That’s your first step. If you can put some pool acid on your cooled alloy and it doesn’t bubble there is absolutely no reason to treat it with sulfur! As far as the process, i’ve done it and it’s a process. Add some sulfur, mix it in, skim off the sludge, and repeat until the zinc stops binding with the sulfur and you no longer have a crust. Basically depends on how much zinc is in your alloy. When you can skim it and you no longer find any oatmeal floating on the top and it looks like clean lead alloy you’ve got the zinc out. It stinks! It’s time consuming! It’s a royal pain! But it works! It’s not something i would do for a small amount of contaminated alloy. It’s just not worth it. And it’s certainly not something i would do because i think maybe possibly there’s some zinc in my alloy. It is a last resort! That’s about all i can tell you about it i don’t know if there’s an actual way to determine the percentage of sulfur to use other than a lot!
Good luck!

thank you.............. I have maybe 60-80 pounds that test positive For zinc. And i wanted to clean it up and use it for roundball alloy.

[Delkal]

Most people use pure lead for muzzle loader roundballs and not an alloy containing wheel weights. You would probably be better off obtaining pure lead for the balls and use your potentially contaminated lead for handgun bullets.

I have some zinc contaminated lead that crud start forming at the top of the melt. I don't let it bother me and just crank up the temperature to cast .45 bullets for my 1911. Some of the bullets do have wrinkles or slight imperfections but they make great blasting ammo and I don't notice a significant difference in accuracy

[popper]

Sulfur will harden bullets. Probably not what you want for balls. And it never stops stinking.

[Dan Cash]

I don't know about hardening bullets but sulpher added to a pot of melted lead will flash a blue flame and produce corrosive fumes which are hard on your lungs and any metal exposed to them. Be up wind or use an effective evacuation system. The process is somewhat dangerous.

[hunter74]

Blend it with pure sb. When below 1%zn it's a castable alloy.

Sent fra min Pixel 8 via Tapatalk

[triggerhappy243]

Sulfur will harden bullets. Probably not what you want for balls. And it never stops stinking.

Have you ever used sulfur to extract zinc or any other alloys out of a batch of lead?

[MUSTANG]

Have you ever used sulfur to extract zinc or any other alloys out of a batch of lead?

Yes. I have.

Sulfur will combine with the Zinc and a scum appears on the surface - scrape it off and it pulls the amount of zinc in the mixture down.

It will also do the same with Tin in the mixture.

In this process; it does harden the boolits cast from the remaining mixture.

Some writings on the subject that might be of benefit:

https://castboolits.gunloads.com/sho...om-molten-lead

https://castboolits.gunloads.com/sho...-Sulfur-Report

[justindad]

Make sure you have the proper grade respirator.
*
I use copper sulphate (eg Zep Root Kill) as a safer way to remove zinc from lead.

[triggerhappy243]

Yes. I have.

Sulfur will combine with the Zinc and a scum appears on the surface - scrape it off and it pulls the amount of zinc in the mixture down.

It will also do the same with Tin in the mixture.

In this process; it does harden the boolits cast from the remaining mixture.

Some writings on the subject that might be of benefit:

https://castboolits.gunloads.com/sho...om-molten-lead

https://castboolits.gunloads.com/sho...-Sulfur-Report

if the sulfur treatment removes the zinc, antimony, tin, what makes what is left........... hard??

[triggerhappy243]

thanks to all who have commented and offered insight. My question is now......... if all the zinc, antimony, tin is removed............ what is it that makes the leftover harder than pure lead? I will try this with 10 pounds instead of the 60 pounds. I am curious as to the outcome.

[mehavey]

Same question here: Why would 'sulfering' a lead alloy make it harder ?
'Tis a puzzlement.



postscript:
As noted above the Gentle Readers want pure lead for patched roundball

[justindad]

Some of the sulfur alloys into the lead.
*
http://www.lasc.us/heattreat.htm

[2TM101]

thank you.............. I have maybe 60-80 pounds that test ***. For zinc. And i wanted to clean it up and use it for roundball alloy.

I have a bunch of lead I bought cheap that I know has Zinc mixed into it. I use it to cast for my smoothbore flintlocks. They go through a lot of lead, and the alloy doesn't matter.

[triggerhappy243]

Some of the sulfur alloys into the lead.
*
http://www.lasc.us/heattreat.htm

I read this and did not see where the sulfur will alloy in. can you point to where you saw it?

[popper]

Solubility of sufur in lead is quite high at higher temps, decreases at lower temps. Correct, it is held in the lead lattice but does NOT form a new molecule. Same with most added elements in lead. It hardens by making the lattice tougher to slippage, like chocks around a wheel. This is the method of ALL lead hardening.

[triggerhappy243]

Solubility of sufur in lead is quite high at higher temps, decreases at lower temps. Correct, it is held in the lead lattice but does NOT form a new molecule. Same with most added elements in lead. It hardens by making the lattice tougher to slippage, like chocks around a wheel. This is the method of ALL lead hardening.

sO, IS THEIR A WAY OR METHOD TO PREVENT THE SULFUR FROM DOING THIS OR AT LEAST MINIMIZING IT?

[popper]

Trigger, not sure what you are asking. yes sulfur will combine ( form a molecule) with zinc to remove zinc. Yes, remaining sulfur will stay in the lead. I did cast for 40sw, pure & zinc <1%, alloy reacted just like pure. 1/2 bullets hit sideways as they were small dia.

[triggerhappy243]

Trigger, not sure what you are asking. yes sulfur will combine ( form a molecule) with zinc to remove zinc. Yes, remaining sulfur will stay in the lead. I did cast for 40sw, pure & zinc <1%, alloy reacted just like pure. 1/2 bullets hit sideways as they were small dia.

i read an article on the lasc page about abatement of zinc and antimony. I wanted to work over a batch of lead (as an experiment) to remove the zinc and some of the antimony and then to XRF test the remaining alloy for content and hardness. My curiosity is killing me.
each step would be tested for hardness and content before and after each treatment.