[Boatanchors] Refabricating knobs and other plastics

[Boatanchor at alliedinformation.com]

I am working to restore some old radios and I have a need for fabricating 
my own plastic parts; knobs, and the like. I saw a great web site on a 
fellow that restored a Hallicrafters S-38 by making his own knobs from RTV 
and cast in polyurethane.

( http://www.stanwatkins.com/hals38.htm )

I think this process sounds just what I need.

Does anyone have a web source for how to do this and where to get the 
necessary compounds for making simple cast plastic parts at home?

Thanks.

Matt, KB8WFH
Boatanchor at alliedinformation.com