View Full Version : Don't Let the Zinc WW's Melt in with the Lead!!

November 6, 2009, 07:48 PM
I have heard this for years, and smelt my WW's with care and at low temps so the zinc can be culled out. Good advice......Uh, Why?

What happens to the lead if you do melt zinc in it too? As far as I know, I've never let it happen, but I'm not sure anyones ever said why?

Usually I learn the hard way but I guess I get lucky this time, so lets hear your horror story of what happened when you didn't start culling the zinc soon enough!

November 6, 2009, 08:17 PM
Zinc is a contaminate that prevents the mold from filling out completely. The Zinc significantly increases the surface tension of the melt, meaning it will be impossible to get good fill. The zinc cannot be easily separated and the metal that has been contaminated is now worthless for casting.

From what I have read, a 1-to-10,000 ratio is enough to cause problems.

November 11, 2009, 11:14 PM
If the zinc floats to the top while youre melting the WW, why wouldnt it float to top in the lead pot? Anyone?? I havent had this problem or know anyone else that has so I cant ask them. I dont know, but it seems to me it would.

November 12, 2009, 07:30 AM
when ya get ahold of some contaminated alloy you`ll know it!!!

Just as Crosshair posted you`ll never cast a good bullet with it no matter what ya do !!

You can dilute it to get acceptable results but I would keep doing what your doing , keep the temps low & skim em off!!!

November 12, 2009, 11:54 AM
how do you tell if ww are zinc

November 12, 2009, 01:42 PM
how do you tell if ww are zinc

There are two reliable ways.

1) Watch the melt temp and skim off the ones that don't melt, these ones are either still or zinc. Keep the melt below 700-725°F (650-675°F preferably.) and you will be fine. Lead melts at 621.43°F while Zinc melts at 787.96°F. Until it gets hot enough to melt, all that Zinc WW will do is float.

2) Drop the wheel weights onto the ground. There is a saying, "If it *tinks*, it's zinc." There is a very obvious difference in sound when they hit the floor. This method is a great way to get people to not be so paranoid and just use the first method because it takes FOREVER to get through even a small quantity of weights. You'll be sick of this method after about 15 minutes.

November 12, 2009, 08:11 PM
Another way to tell zinc weights is some of them are stamped with the letters Zn on them and they are rivited to the steel clip, not poured onto them. A lot of them will be shiny too compared to the dull drab color of lead weights.