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I am looking for some advice on how to design my product for silicon tooling.
I intent to have it made in 50 shore rubber. My tricky part is that it has to house a small gps device.
Any suggestion, however ridiculous, would be greatly appreciated.
Same geometry design rules apply as with plastic injection molding. You might consult with your silicon molding vendor and ask for recommendations.
Nothing looks irregular about that part. That could easily be injection molded, the silicone also isn't a problem for injection molding. For low volume stuff, especially if you don't have the capital to cover the tooling for injection molding, you could have a rapid prototyping company do urethane castings. They are temporary molds that can be made quickly and cheaply to pump out lower volume stuff at a fairly reasonable cost.