Combination of Digikey, Amazon… I’m starting to look at mouser and Alibaba as well. I use McMaster Carr for hardware components. My two thoughts are:

1. they’re not good for mass production because they have a markup. However, if I find a good product through them, I’m sure I can just reach out to the manufacturer of the parts… however…
2. picking the right part is a bit tough. For example, let’s say you want to step down from A/C to DC voltage. Well, I see transformers all over the place in terms of price. And while I can certainly come up with constraints such as what’s the input voltage range and output voltage and current range, I can’t help but wonder if I’ll be making a mistake picking the wrong thing. And for DC motors, honestly I thought they were supposed to be super cheap, but on Amazon they’re usually $10-$15 and even then I can’t find one with my torque requirements. So on the one hand, I thought 12-24V DC motors were way cheaper (maybe incorrect assumption), and on the other hand they’re hardly cheaper than similarly sized stepper motors… which is confusing to me because I thought stepper motors were generally much more expensive.

So either my expectation of how much they cost is wrong, or companies usually get really cost effective suppliers that I can’t see from my own searching.

Wow that’s really generous of you, thank you! I will DM you!

Thank you! Yes, proof of concept is designed in CAD and functionally working via 3D printing, off the shelf hardware, Arduino based software I programmed. However, it doesn’t make sense to ship an Arduino in each product because the cost of an Arduino is high since it comes with a plethora of I/O that for a broad set of use cases.

So migrating to a purpose-driven board seems to be pretty standard. Yes, I believe I would want to get help on that, as the time it would take me to learn PCB design and part selection might be much longer than I could afford.

But at least the scope of that part is clear.

But for things like DC motors, AC to DC converters, even down to a particular capacitor or switch… how do you go from off the shelf parts to an optimized set of cost effective parts?

Thank you! That’s helpful…by the way are industrial engineers usually a part of an industrial design firm, or are they separate?