[singleshotbuff]

Hey guys, newbie to casting here.

I've been reloading for 15 years but am just now taking up casting. I'm using a propane burner (turkey fryer) and an iron skillet to clean metal and make it into ingots for casting with an electric furnace later. The metal is range scrap from a local indoor pistol range. I know this probably isn't the best metal but for what it costs me ($0.00), I'll use it for low velocity handgun rounds and save the wheelweights for the rifles later. My question is, when I melt the metal and skim off all the junk (jackets etc.), then flux the metal, a sort of yellowish gold colored scum forms on top of the lead. What is this? Is it junk to be discarded or ingrediaents to be mixed back in? Also would a different flux make a difference? I'm currently using candle wax, and I have Lyman bullet lube available to flux with. Any help or input is appreciated.

SSB

 

[Jack Monteith]

Hi, SSB:
That yellow scum is likely lead oxide. If so, it's unhealthy for you. Some of it's likely already in your range scrap, but you'll make more if you overheat the melt. So turn the heat down as soon as your lead melts and just keep it fluid. Overheating will burn off your tin too. Check out this article and the others by Mr. Fryxell.
http://www.sixguns.com/crew/simplefluxing.htm
I find that wax is OK for flushing the dross off wheelweight clips and fluxing the dross off already clean metal, but it burns off too fast to do a good job of reducing the metal oxides. A half inch of sawdust takes about 15 minutes to burn off and does a much better job.

If you can't flux off the yellow scum, dispose of it safely.

Bye
Jack

 

[Paul Nichols]

Yellow Scum

I agree with Jack and the oxide factor. In addition, it stinks. Be sure that you are casting with lots of venting or outside. (On rainy days I cast in the garage with the door open and a big fan at my back. Range scrap to me has always been a pain to clean and work with. Wheel weights are not tough to come up with cheap or for nothing if you really ask around. Hit the junk yards for linotype for a mix for rifle bullets. I have fluxed with candle wax, bees wax, sawdust etc, and some commercial products. All work to various degrees, but time considered, usually end up with beeswax. As you get into this more, you will want I am sure a bottom pour furnace, and if you are serious about the whole thing, and want to shoot a lot, go with a 20 pounder. Good luck!
Paul

 

[singleshotbuff]

Guys,

Thanks for the replies. I turned my burner down tonight and processed 25lbs of metal. It seemed to help. I'm gonna get a thermometer this weekend and continue my experiments with the temp. I'm also gonna try the sawdust fluxing.

Any idea what temp I should be shooting for?

I'm thinking I may eventually mix this lead (since I have hundreds of lbs of it) with wheelweights to harden it before making bullets out of it.

 

[MikeG]

Get a casting thermometer, if you don't already have one. Also the Lyman or RCBS cast bullet handbook.

If I recall.... tin starts to oxidize and comes out of the mix around 700F (bad, you want to keep it in the mix) and lead start to evaporate around 900 (Very bad!).

When you are rendering down old junk, if you keep the pot just above the melting point of lead, sometimes you can skim out undesireable stuff like zinc and copper before they dissolve into the mix. Don't have to have a casting therometer for this, just heat until lead isn't 'lumpy' any more, then cut heat, flux, and scrap out gunk.

 

[Capt_C]

I think it takes more like 1100-F to get lead to enter the vapor-phase. Casting temperatures should run 650 to 700. Still, good exhaust is critical for safe casting IMO. --CC