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trip_sticker
September 24, 2009, 03:12 PM
I just finished melting down 70 pounds of wheel weights. I scored just over half a 5 gallon bucket from a tire shop that I hadn't tried before. Anyway, when I melted them down cleaned off the dross, and fluxed them, I kept getting a bright gold colored film over the surface. I haven't seen this with other batches before. Any idea what this golden color is?

Unclenick
September 24, 2009, 08:00 PM
Some metal oxides change color with temperature. I am assuming it goes away when the alloy cools? Chances are if you used a slightly lower melt temperature you wouldn't see it. What it is an oxide of, I can't say? I assume wheel weights have a number of contaminates because there is no motivation for them to spend money on pure alloys for the purpose.

trip_sticker
September 24, 2009, 08:17 PM
No, the yellow color was still there when the ingots cooled. I'm not really worried about it, I was just curious if other peolpe had seen this before.

DiscoRacing
September 24, 2009, 08:20 PM
new one on me.... ive never seen that before on mine... tho i have heard that they are adding new alloys to the new weights...

IllinoisCoyoteHunter
September 24, 2009, 08:55 PM
It might be real gold. Did you get your wheel weights from a leprachaun? :D

Rusty W
September 25, 2009, 10:33 PM
I've seen the same gold tint in my Lee pot when I was casting some bullets just the other day. I added about 1/2 of a pound of 60/40 solder to 10 pounds of wheel weights to make some 44-250-KT's. I think it's the tin content making the gold color. I've smelted pure lead and it gets a blue/purple color to it sometimes.

Unclenick
September 26, 2009, 06:01 PM
Hmm. I'd still look for an oxide layer. Did you score an ingot with a file and see if it is through and through, or just on the surface?

Another possibility is some kind of scum from the stick-on wheel weight glue. Just don't know?