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0 pointsCamperBob211y ago0 comments

The real solution is to make sure your product is above $100 (preferably significantly) so you can actually 3D print the required plastics (which will be around $10 per part). Now, you can tune your plastic parts and you don't have the NRE of molds. After you have everything tuned and have some volume, THEN you can cut a mold. And, you may never cut a mold--you can print over a thousand parts at $10 per part for $10K. How many Kickstarters ever ship more that a thousand of anything?

Good points there -- I have a scenario in mind that resembles this example. Do you have a favorite 3D printer for small instrument/device cases? Or do you outsource that work to someone who does?

So, I'm above $50K for injection molds without blinking for even a VERY simple product.

Also, something I've never understood about injection molding is why the hobbyist-accessible CNC revolution of the past 10 years or so hasn't reduced the cost of creating molds. If I do a GIS for "injection molds," it shows me a lot of pictures of things that, although concave, could easily be built by aggregating a small number of machined parts.

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bsder11y ago

> Do you have a favorite 3D printer for small instrument/device cases? Or do you outsource that work to someone who does?

Outsource. I want a useful 3D printer with materials like nylon, not a MakerBot. There should be people around in any reasonably sized city. I believe that some of the Solidworks resellers now do 3D printing as a service.

One thing that people continue to underestimate are silicone molds. 3D print the positive--create a silicone negative mold from the 3D positive. Now you can make your own parts out of liquid silicone rubber--some durometers of which are almost as hard as some plastics.

Yes, this is incredibly messy, time consuming work, but if you have more time and/or hands than money, it's not a bad choice.

> Also, something I've never understood about injection molding is why the hobbyist-accessible CNC revolution of the past 10 years or so hasn't reduced the cost of creating molds.

Because no injection molder wants to deal with people producing <10,000 parts. The setup time on the injection machine exceeds the profit.

I don't even need a CNC machine to create a metal mold--people did do this by hand for a whole lot of years. However, even if I could produce the mold for free, the molder doesn't want to waste the time on me.

For that reason, practically every successful electronics component producing company has both a machine shop and an injection molding machine on site. Both of them tend to sit idle 90+% of the time, but every time they get used, they save $50,000.

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