It's important to clarify whether or not it will be for-profit or non-profit. There are effectively no case studies describing successful for-profit open source technology. You'd be breaking new ground.
Yeah, do you have anything more specific than "I want to make stuff?" Unlike software, hardware needs to consider cashflow as integral to the project. Even prototyping something physically costs money, unlike software which can usually cost only pizza and sleep. So, where the money comes from needs to be part of the very first steps as the concept develops. Is it going to be a hobby? Is it going to be contract work? Is it going to be run on donations?
My suggestions is to find an existing company/group that is doing open source work and manufacture hardware for them on a contractual basis. Everyone who committs to open source as a philosophy tends to want to help exand the number of open source resources, so they might use you even if you're a bit slower and more expensive.
On the other hand, maybe you don't want to be a manufacturer so much as an educator/innovator. You could develop and troubleshoot open source manufacturing processes and tools, then if they work you could sell them. Maybe ask around to see what small-scale manufacturing stuff people would pay for. Like a PCB assembly line for all the guys who like to make prototype electronics. Or a modular machine shop so people can start with a lathe, then turn it in to a mill, without buying an entirely new machine.
I dunno, man. I have to speculate because you haven't said what it is you want to do.
Okay, so it's a hobby.
If you can start to contribute more/better software that will be a real help to the rest of the community. hell, just contributing to the FreeCAD documentation would be awesome. I've barely figured out how to do anything with it.
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