my first pour, a miserable failure.

Well i produced a perfect copy of the sprue. The foam of the skull disappeared but no copper skull was produced.

 

No, it didn't occur to me to take a picture before hand. I haven't found anymore foam skulls, I do have some hollow plastic skulls. Would that work?

 

I know it seems backwards, but practicing with aluminum helps you get your arms around everything. People have varied results with brass and foam, copper is tougher to cast than brass or bronze.

Thin plastic likely will not vaporize fast enough to allow an adequate casting, and if it's thin, you'll likely have the metal front cool before it can fill much of the intended space.

In your first try the copper may have cooled off before the casting was complete.

If you don't have a skull you like you might try just casting a simple shape like a rectangle of styrofoam. When you can do that successfully then you have a better shot at casting your next skull you find.

 

Yeah I tried a disk this morning I'll post the pictures soon, it's not pretty.