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Ed Huntress
 
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Default Strongest / Toughest material moldable in a Silicone RTV Mold?

"Tim Williams" wrote in message
...
"Ed Huntress" wrote in message
...
If you want metal, spincasters have cast aluminum diecasting alloys in
silicone rubber. The rubber is a very hard, high-temperature version. It
doesn't last for many shots but it does work. It doesn't much resemble

the
common RTV type that's used for low-temperature casting.


I would suggest ZA-27 (27% aluminum, balance zinc, you can whip it up with

a
dollar or two of 1983-or-newer pennies and some scrap aluminum). Strong

as
mild steel, hard as heck, melting point less than aluminum (circa 1000
degrees).

The Zamak family of alloys (look into ZA-8) have
tensile and compression strengths on the order of 40 kpsi and good

bearing
properties.


Oh...there you have it

I don't like the looks of ZA-8, at least the stuff I've made; makes big

huge
crystals, visible when you break a face.

Tim


What kind of mold are you casting it in? If you're using plaster, it chills
too slowly for ZA-8.

Ed Huntress