Hello! I'am new here and have (almost) read all topic's in this section, but could not find an answer. My idea is to shape a body with clay and then make molds from this body to make GRP-parts. (I hope you understand what I mean) Will this give problems or is it no problem to do this? I have seen it on Discovery Channel doing so, but also heard a story that it caused a lot of problems with the first Lotus Elise. So is it a "go" or should I use other material (PUR) for the masterbody?
The first question I have is, how many parts are you going to be making from the mold? If it is a case of making just one part then you can design your body shape from clay giving you plenty of latitude for design changes and then take plaster molds from the master design. The plaster mold will be good enough to produce one quality part and you still will have your original design. This is assuming that the molds come off of the clay surface with minimal damage.
You may be lucky enough to get two parts out but when releasing the fiberglass part you will undoubtably encounter mold damage. If you require a small batch run of parts then the mold would have to be made from something more substantial such as fiberglass. With a fiberglass mold, saving the master clay will be more of a challenge and no doubt there will be more damage but the trade off is you will have a mold where you can take multiple products from.
The third choice is to make a plaster mold, produce a master part from that mold then make a fiberglass mold from the master part. This should give you the best of both worlds. A master clay for reference and a master mold capable of producing more than one part.
Steve, thank you for your answer. I want the master mold made of fiberglass, that for sure, but I have not decided yet if I need the master clay as reference I think I try some small parts first. Regards, Martin
