I was thinking about this question today as someone used our work printer for some personal stuff.
As for me, I am printing little things that I would say make it worth it. I’ve printed lens adapters for my camera for example. That’s worth a good 14 to 30 bucks per print. My most favorite photo was with an adapted lens that came from a projector. I also printed IEMs and those things are worth it. Listening to music is second to none on those things. Plus I printed the same shell but for ear protection and again the fit is perfect and sure there’s post processing to get smooth surfaces but in the end it looks like a professional made it. So I think 3d printers are worth it.
Haven’t made any money from mine nor did I ever intend to. Well, the thought has crossed my mind, but I get more of a thrill out of the looks on peoples’ faces when I gift them something off my machine at no cost to them.
My girlfriend has recently been asking for a lot of customized crochet needle hooks for her collection. They’re not hard at all to design and then send off to the printer. She’s so excited and tells everyone about them and how much she adores them. She’s crocheted me a blanket which I adore too.
I have made a lot of practical things for myself. I don’t know if any of it would ever make up for the amount of money I invested into the 3D printer, monetarily speaking, but the amount of time and energy saved has been worth it when I really needed something custom made and on the fly. The creativity and knowledge built up from using this has also been a plus. Been a nice talent to grow and expand upon and a neat thing to bring up to people.