Hey all, heres my story..

I've got an idea for a new part I want to design for a car.  Its a very very simple part, but being the newbie that I am, I have no idea how to make a prototype that is suitable to be used for mass-manufacturing.

My plan was to take existing PU parts, sand and shape the part to what I like.  Then take the PU prototype to a plastics manufacturer in my area and have them mass produce it.  

Is this at all feasable?  Or do I need to make the original prototype out of a certain type of material?  One of the people I called said that I would have to have a prototype made out of aluminum first to be used as a plug, I thanked him and hung up because I have no ability to shape and mould aluminum.  :)

this is a project in my garage pretty much, but I'd like to mass produce my product.. whats the best way to do this ?

thanks for listening, and hopefully im coherent :P

A prototype for shape and fit only can be made of anything from Kraft wood or balsa to plaster of paris or clay or polyester resins.

If you want to test the prototype for function, then material properties become an issue.

Once you have the shape, moulds can be made from that shape by a number of methods, including copy milling, casting in silicone rubber, casting in epoxy, digitising then using a CAD system. Digitising can be done with a stylus or by laser.

Regards

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I have experience in this area. As a design guy myself, i designed aftermarket instrument gauge needles that contained a fluorescent mineral. Had tooling made and injection mold the parts. I provided my hand made parts to the in house CAD guy who made the tool from T-6 alluminum (Soft Tooling). It is a little cheaper than steel molds. But it is very durable. To keep costs down, stay with a simple 2 part mold and if your part is shallow enough, go without ejector pins.