I'm currently experimenting with making silicone molds for casting. I'm not interested in the commertially available molds and want to make my own. For financial reasons I use the cartridges of transparent silicone commonly available in home construction stores.
In my first experiment I wrapped a plastic bead in silicone to make a mold. The silicone took on the color of the bead, so it clearly reacted and melded with the plastic. I was unable to remove the bead from the silicone and threw the whole thing away.
Next I carved an object out of candle wax and covered that in silicone. When the silicone was cured, the object was covered by a thin layer of very white wax, almost like a frosting. After removing the object from the mold the white residue stayed behind and the planes of the object were not cleanly molded and full of imperfections.
Then I tried a special "casting putty". It is not polymer clay like Fimo, but a putty designed to seal gaps in molds before casting. It gets soft and malleable at body temperature and hardens when cooled down. Again, the silicone melded with the putty. I haven't tried polymer clay because I noticed that I couldn't make the planes of the putty object as smoth and shiny as I wanted.
I wasn't expecting silicone to react and meld with materials, least of all candle wax.
Is there a material that can be easily cut and carved into clean, shiny planes but that does not react with silicone? Or do I have to coat my objects in another material to protect them from the silicone?