While the patent discussion is always useful, the original poster`s question was regarding prototype development.
We have a wonderful resource here in the Bay Area - Tech Shop in Menlo Park. We found out about them through SuN member TechShopJim, who started the place, which just opened last October.
Tech Shop is amazing! They have every kind of machine you could imagine for fabricating prototypes and beyond out of metal, plastics, or just about anything else. You pay a low daily, monthly, or annual fee, plus $30 per class to get checked out on any equipment you are interested in. If you don`t know how to do something, they have people there who can help. They also have a great guy who does prototype design work for a separate fee.
We are in the process of doing a redesign of our product there. Their guy is doing the more complex design work, then we will be cutting our own molds (our product includes injected molded plastic parts). After we get the plastics shot elsewhere, we may actually do our own assembly at TechShop for the first batch of units.
So check them out www.techshop.ws
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