I got into 3D printing a little over a year ago and have been enjoying the hell out of it.

It's the ultimate geek hobby. There are different mechanical systems you need to understand inside and out. There are physical properties of different plastics you simply have to understand in order to see what's going on. "Why didn't it work?" becomes a complex question, and you have to understand the fundamentals of how 3D printing happens in order to begin to answer it.

You can manufacture nearly any part you can imagine right in your home. Some applications are silly - desk toys, figurines, busts. Some are practical - tool holders, replacement parts for commercial products, etc. The best are practical and custom. Those are the things you design yourself to solve an incredibly specific problem. For example, I had a pair of kitchen tongs I really liked, but a plastic part disintegrated and they wouldn't lock anymore. A new pair of tongs is only $10, but it's a shame to have to toss the old ones because a small piece broke. 30 minutes of 3D modeling and 20 minutes of printing and the tongs are working as before.

It's less about printing stupid little plastic things as it is about the freedom. 3D printing lets you create anything you need from scratch, instead of having to source a commercial product/part, or physically fabricate your part from wood or metal. You have unlimited freedom to create what you need without depending on anyone else. Even though some prints can take hours (and days), that's still faster than chasing down an international vendor to find an obscure part.

All kinds of things can go wrong (especially with DIY printers), and it's the constant R&D part I love the most. Sure, your printer could be stable and crank out stuff reliably, but where's the fun in that? There's always a new horizon. You can try to increase your print area, or fiddle with your print speed to make it faster, or try new materials, like wood or flexible material.

Do any old farts remember the PC kits in the 70s and 80s? When Radio Shack was relevant, they sold kits to build your own PC. It was a wild west - different parts weren't compatible. Lack of standards. Lack of codified "best practices" to describe how things ought to be done. It was a bunch of hackers figuring out what personal computers might be good for. Now we have multi-billion dollar industries, ISO standards, and university programs teaching "how computer stuff should be done". The hardware wild west is over. 3D printing today is where PCs were in the kit days. Nobody knows what the end game will look like because it's still changing so fast. It's exciting to be in on the chaotic action, and exciting to think what home manufacturing is going to look like in 20 years.