Daryl,

Always outdoors.

Have you never accidently had a valve stem get into the mix? If not, you have a charmed life. The way I get my wheel weights is in a 5 gallon bucket from the tire store. It isn't entirely unusual to find a stray valve stem or two in with the weights.

If you are casting indoors I hope you use good ventilation. Lead fumes are said to be dangerous.

Curl