Depending on how accurate "accurate" has to be and what material you are using for the prototypes, Latex (sold as molding compound at places like Hobby Lobby and some hardware stores) will make accurate soft low temperature molds in which you can make copies with plaster, casting wax or, perhaps the best, casting resin which is also sold at the same places. From places like MCS
- posted
19 years ago
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you can get casting metals that melt below the boiling point of water and can be cast in the latex, but cost a small fortune. You can use the wax copies to make lost wax molds in plaster or investment for casting in lead, zinc, or aluminum at more or less reasonable temps and glass and brass at higher temps. RTV is a casting rubber developed by GE that is available in liquid (and paste but you don't want that) that will stand temps to molten lead for several castings and perhaps molten zinc at higher temps.