Anybody here ever heard of making castings of plastic kit parts by using rubber mold material, and then filling the molds with auto body Bondo? I’ve seen it done it with amazing results. Hundreds of tunnel portals, buidling walls, windows, etc, can be easily reproduced, but I can’t find details on how to make the molds, etc. Anyone done this before?
Lots of info available online to make rubber molds to use with any number of casting materials. I use a two-part silicone rubber from Smooth-On and they have excellent online instructions: http://www.smoothon.com/silicones.asp but here are countless other suppliers such as Micro-Mark http://www.ares-server.com/Ares/Ares.asp?MerchantID=RET01229&Action=Catalog&Type=Department&ID=64
The interesting question here is what casting advantages Bondo might have over other materials such as plastic, Sculptamold, Hydrocal or other plasters.
Wayne
Bondo is fairly heavy. How does it compare to hydrocal, sculptamold, etc.?
Bondo is a brand name. It’s actually a polyester based plastic filler composed primarily of clay and talic.
It can be useful for castings, however, for those of you that live in very humid or wet climates be aware that the cheaper plastic fillers, such as Bondo, tend to absorb moisture, which over the long run can lead to cracking as the material becomes more brittle…
Quality plastic fillers, such as the 3M brands may work even better as the texture is less porous.
Body filler is very useful for many applications and is worth experimenting with. I can still remember my late father using it for minor drywall repairs on his carpentry jobs.