What is it?

[silly goose]

Hey guys, yes I'm new. Started casting a couple weeks ago, and was having a good time. Smelted down wheelweights into ingots. used a propane burner and cast iron pot. Don't have a thermometer. Meltod some of my muffins in 10lb bp and fluxed. Couldn,t get that mirror finish that I was able to get before. Noticed yellowish film on spoon and sides of pot. Fluxed several times w/old candles, and a wood stick. Have not noticed clumpy oatmeal like consistency that I have read about with zinc. Also having trouble getting 45 cal bullets to fill out completely. And they have like a partial frosting look, maybe galvanized looking in spots. I couldnt get bullets to fillout (some werent too bad)or frost with pot all the way up. Is it zinc? What now? I have about 120lbs that may be contaminated. Decoy anchors, sinkers?

[docone31]

The yellowish colouring is a colour I get once in a while. It is not something I worry about.
Your clumping might be an area of zinc in the melt. Might.
Were It me, I would make ingots of the melt you have, seperate it from the rest, add some pure lead. Roof Boots work well.
Crank up the heat and see if it is still clumping.
I do run zinc in my melts. I cast with it. It takes high heat, but I get it to work. Not a lot, but some. I have to run my melt at top frame, and the molds hot.

[silly goose]

I dont have any clumping, just this yellowish stuff, and a constant coating of an elasticky skim on top. As well as less than great fill out. I don't know.

[KYCaster]

The only time I've seen a yellow crud was when the pot was way too hot.

Too much heat can cause poor fill out and localized shrinkage.

Jerry

[silly goose]

Messed around with it some more today. Tried it cool, tried it hot. Best fillout hot, but still not great. Emptied pot and went with my first batch of ww ingots. Problem solved. When I get some good boolits put up, I'll tinker around and add some pure lead to the mix, bout the best I can do I suppose.