Any reason I can't melt lead in an old propane tank?

[Cucumbermonkey]

I have a ton of lead that I want to re melt and try to remove what I believe is zinc. It was made from wheel weights and I believe it's contaminated. I didnt do it. Can I cut the top off an old propane tank and use it for a big pot? Ive gathered here that I can use sulphur or copper sulfate to remove zinc from melted lead. Does that sound right? Thanks Im new here and pretty new to casting. I probably wont be posting much because I dont know a lot and Im just trying to sponge up whatever information I can. Thanks.


Edit Mods I put this in the wrong section. I meant to put it in "Casting Equipment" Can you move it please?

[dbosman]

Lots of folks use the bottom half of propane tanks. Make sure the tank is safe to cut with a cutoff wheel. A mistake would be explosive.
Now, there is or are threads here and online about experiments on using sulphur to flux out zinc. Read those and decide if the effort is worth what the return might be. If there is a sinker caster in your area, they might buy your contaminated alloy.

[Moleman-]

Made a foundry from a 20# propane tank. Took the valve out and filled it with water to make sure there was no gas left inside. There was a bunch of really stinky propane smelling oil in it, so it still smelled like propane. Used a cutoff wheel to make a hole then switched to a sawzall.

[trapper9260]

When you do use the tank .Make sure you keep it hot.Because it will hold the heat like cast pot dose. I made one and it was from a tank for the thing they use in place of free on. I use a wood fire for what you looking of doing of melt. As for if you just start to melt the WW the zinc ones will float.That is with low heat that only the lead will melt.

[jeepyj]

That has been the key to my bulk lead clean-up for several years. A cut off tank coupled with an old propane turkey cooker makes it quite easy to clean up several hundred pounds at a time.

[Ballistics in Scotland]

You can just make sure the valve is out - really sure - and heat it up on the burner before any cutting, to make sure any residue is evaporated or burned. I can't imagine it doing anything drastic if you start it slowly with a low flame and stand back. If you didn't have a burner, why would you be doing it?

[725]

If you can remove the valve and refill with water, before torching or cutting, the volatile vapors will have been driven out.

[Ballistics in Scotland]

Volatile isn't the problem. It is the residue Moleman mentions. I confess I have just gone to my workshop and shaken an empty propane cylinder I have, without hearing anything. But if it is gooey, water isn't going to lift it out.

[Budzilla 19]

That stinky propane smell, is probably mercaptan, the stuff that puts the "smell" in propane or natural gas! In natural gas systems, mercaptan or "odorants"is added to be able to detect leakages. Safer to use the little tanks for helium balloons like you buy at the local store! Safe to cut and easy to do! Just my .02

[jeepyj]

Speaking only from what I did not advising anyone to do anything. My method was I took the old empty tank with me when I went shooting and shot a hole in the top half with my 357 then I took a long stick with paper wrapped around it and lit it on fire. The vent burned for approxametly 15 minutes after that I shook it up and re-lit this time it burned for just a few minutes. Next I transported it home and tried to light again this time it didn't really light. Next I put a band of blue tape around it showing where I wanted to cut then filled with water from the garden hose and took a 4" cut off and zipped it off. The smell is horable so I sat it on the burner and gave it a light to get rid of mercaptan smell. Mine holds about 140 pounds. If you decide to to play around with method on be sure to wear all your safety equipment. Once again this is only MY experance and I'm not an expert with the effects propane and the do's and don'ts and advise anyone to use there best judgement.

[dsh1106]

I just completed a project that required I do this.

I had to melt and pour over 1000# of pure Pb ....

I used an old propane tank cut at the top radius of the tank. I purchase a bayou burner @ 200,000 btu. The tank will hold just shy of 400# filled to within an inch of the top.

Scott

[anthont1]

I just cut a old freon tank in half works great for my uses. Used a cutoff wheel took all of ten minutes. Old freon tanks are easy to find if you talk to hvac guys and the freon is not flammable so no worries when cutting, at least for me. Just open the valve to make sure it is empty, freon can get pretty cold.

[kmrra]

The best way is to take the valve out , they are a bugger to get out I took mine to the place where they fill them , and they took it out for me , they have the tools and vice to hold the tank , cause they are in there tight tight

[Cucumbermonkey]

Thanks for all the replies guys. I was unable to remove the valve so I'll fill it with water to purge whatever's in there and then take a cutting wheel to it.