im wanting to make product . it needs to be very strong and made from polyurethane. i understand i will need to make a silicone mould but my problem is here... i cant use the model i have now as i need to make it much small and since its made of rubber its impossible for me to do this. so im wondering is it possible to make a replica of the model using clay or some thing like this. then using the clay model to make the silicone mould. then i can make many of them out of polyurethane. Tom