Wood ingot molds

[Longwood]

Someone was asking about wood for molds.

http://www.youtube.com/watch?v=nKJWrc0VEoQ&feature=related

[letsmeltlead2693]

Neat video, the lead bubbles like boiling water.

[CollinLeon]

I suspect that it is either the moisture in the wood or the gases produced during the burning of the wood that is causing the bubbling...