I've purchased several custom printed flip caps for optics. And they weren't printed from a hobbyist site. They were printed by a company that manufactures custom parts.The quality is way above this and even cost less. By flexible option, I'm referring to how you can modify it, not the material it's made out of.
Yes, that makes sense that a piece of plastic would cost less plastic plus USB connector, pins, and whatever else is inside, plus a person or machine to solder components.
I understood what you meant by flexible... And if you're capable of making your own things, that's great. It would be awesome if we could all make these types of things for ourselves. I think the fact that people buy this instead shows that not everyone can do that. That's capitalism, isn't it? If you can't do it yourself, you pay someone else to do it.
I've dealt with high end plastic mfrs and their take is 3D printing is for prototyping and not something you want for end use. A 3D printed product will not have the strength or clean look that another manufacturing process will have. I would show you a 3D printed prototype plastic snap on cover that is now in production except the 3D printed version broke during my testing and I threw it away. The injection molded version is still in production and selling well.
Of course this is the case. The injection molding process is going to create a higher quality part that will hold up to the repetitive use, especially with snap components. But as far as I have seen, it's then a case of economies of scale. The molds have to be fabricated. If there's a place out there that will charge you the same for 1 unit as they would for 10,000 units I would love to know. I create marketing miniatures of product for our sales team to bring along and we're always wanting more stock but the cost of an engineer on the payroll already clicking print in the morning, and cleaning supports in the afternoon comes out cheaper every time we look.
Overall, this was a post asking about the quality of a product on ebay. A few people said it was good, worked, and looked better than the photos on the listing. Now we're on the second page of this discussion going back and forth about building something yourself vs buying. And it doesn't seem like either of you bought one. Someone probably just made one and had some spare components left. Other people bought them. I don't see why all this back and forth is really necessary.