How did you come to have the skills to design and build whatever it is you manufacture? I'm guessing you have a mix of mechanical and electrical background.
I always have ideas for little products (some involve electronics others not) I'd like to build, but how to go from raw idea in my head to working assembly, I'm lost on: choosing motors, control board, mechanical reliability, etc. Maybe I just need to read some ME books, but if they are like math and physics texts, there is gulf between the text how to do build something practical.
I have a background in electrical engineering, but a) it's 20 years out of date (I got the degree and immediately went into software), and b) my training was somewhat niche in that I focused on microprocessor design. So I'd never (for example) learned how to lay out a circuit board, or deal with mixed digital & analog effects (well, at least not at the scale of a PCB).
Recently I had a small project idea that involved a pretty basic PCB. I was surprised at how easy it was to teach myself board layout (using KiCAD) and several related skills. You can get one(ish)-off PCBs manufactured by PCBWay or OSH Park on the cheap. I haven't finished the project yet (supply chain issues), but I'm pretty sure it'll be successful, and fairly cheap, considering.
There are lots of resources online if you need more external help learning. Two I was pointed to (but haven't really dug into too deeply yet) are All About Circuits (https://www.allaboutcircuits.com/) and Ultimate Electronics (https://ultimateelectronicsbook.com/). For the more physical aspects, YouTube has been a great resource -- for example I needed to solder a 5mm x 5mm QFN IC to a breakout board, and didn't want to spend the money on a high-end rework station. A random video on YouTube taught me how to do it with some flux, solder paste, and a cheap hot air gun I bought on Amazon.
Next I'm going to look into getting a 3D printer, and learn how to design stuff for that. I expect the learning curve there will be higher (at least for me), but I don't see it as out of reach.
> Next I'm going to look into getting a 3D printer, and learn how to design stuff for that.
I'm in the high power rocketry hobby and a 3d printer was a game changer for me. I have a prusa i3 mk3s+ and can't recommend it enough. For software i originally started with onshape but then went to Fusion360 because that's what everyone else in the hobby uses. Learning curve is steep but there's tons and tons of good material to help you learn. My workflow is Fusion360 then PrusaSlicer then save to sdcard then print. You can really optimize further but i don't sell 3d printed parts so it's good for me.
On the other hand, i do have a big arse laser and i stood up a little website and sell a simple cutting service to my buddies in the rocketry hobby. I like my website, i have no database! I actually use some metadata features of the stripe api for my order database hah.
I always have ideas for little products (some involve electronics others not) I'd like to build, but how to go from raw idea in my head to working assembly, I'm lost on: choosing motors, control board, mechanical reliability, etc. Maybe I just need to read some ME books, but if they are like math and physics texts, there is gulf between the text how to do build something practical.