First, you will need to have your 3D work done before having a prototype done. Find a designer in your local area because it is easier to sit down face to face and describe you ideas in person. Once you have your 3D CAD model complete you can have a prototype manufactured.
While it is often cheaper to have a prototype done in China, the best solution is to work with a domestic company that already has contacts in China. Find a local prototyping firm and ask them if they outsource any work to China, and do they have relationships with reputable vendors there. I would not recommend trying to work with China directly.
We sometimes use China sources for plastic injection molding tooling. We have good relationships with several manufacturers there, but we prefer to use ones with US based offices and contacts as it insures a more problem free transaction.
Premier Plastic Molding & Tooling, Inc.
I am a plastic molding manufacturer here in the US. I cannot tell you how many projects are making there way back to the US from China. Wham-o has moved production of Frisbees and Hoola-Hoops back already.
Mostly small market things are coming back first. Companies with production being done in China are having increasingly hard times getting decent service and the price keeps going up. Transport cost have gone through the roof.
Watch this new video from MSN http://video.msnbc.msn.com/rock-center/46198559#null
Made in the USA is making a comeback!
Premier Plastic Molding
Tooling for injection molding is relatively expensive. Why do you say aluminum tooling will not work for your project?
I am running aluminum tooling right now that has produced over 250,000 parts and is still in good shape. While many people say aluminum tooling is short life or temporary tooling, that is just not the case.
However - aluminum tooling is not always the least expensive tooling anymore. Most often the least expensive tooling is built in P20 steel off shore, then have it shipped to the US for production.
Really - you need to do an interim step first, which is to have a prototype or prototypes made. This will prove out your design, give you a working product to use for marketing and or fund finding, and give you an opportunity to make any design changes needed before you spend the big dollars on tooling. Remember - tool modifications are hugely expensive.
There is a more detailed explanation on my website of the steps you should follow to develop a plastic product. www.premierplasticmolding.com
We sign NDA's all the time. Personally I think that DNA's and patents are things promoted by the companies that are trying to sell patent and NDA services for a living.
As a manufacturer, I really am not interested in stealing your idea. I make things for a living that other people invent. I would not be in business today if I stole other peoples ideas.
Finding an investor is hard. Money is tight and even the big companies are holding back on new projects. I have a plastic injection molding company and we make a living taking small projects and getting them started with plastic product.
You need to have a prototype made - you will need it to find an investor, or even more importantly to make sure your concept is sound. Quit worrying about the patent and get a product in hand that you can show and demonstrate.
I currently work with a company that does equipment for law enforcement and times are tough in their business too. Budget cuts have made them cut down on their toys quite a bit. If you can market it as a money saving tool - you will do much better.