Well see, that's kind of a big deal, selling the means to consumers. It's open source now making it the veritable Wild West of self-manufacturable plastics. And so much of our societies structure is already built around plastic bits and pieces.
The cost benefit ratio is the issue here, and a 3D printer needs to be cheap and able to produce high-quality pieces at the same time. The technology's just not there yet though, but it will be very soon and that's what to look forward to. I mean something like this, if marketed and utilized properly, could make a huge dent in almost every consumer market imaginable while cutting out shipping costs to boot. The possibilities and sheer utilitarian values are staggering, honestly it very well could put your favorite keycap manufacturer's out of business over a weekend.
I highlighted a section of your text to make it clear what is irritating me about this hype surrounding 3D printing.
In more than 30 years, the industry has not been able to produce materials and methods of printing to rival molded plastics or machined metals. Why do you think this is going to change "very soon"? It's great that people see the possibilities, but not so great that they ignore the downfalls. Just because 3D printing is getting a lot of exposure right now doesn't mean it's the solution to all consumer's problems.
The cost and effort required to print an article are still far more than a mass-produced molded version of the same thing and the quality is lower. It still makes more sense to make accurate metal molds and then mold plastic articles in bulk than to 3D print them. And I don't see the gap closing, since there has been plenty of time to improve things, but the main issues are still not solved.
So sure, you may be satisfied with an inaccurate, rough surfaced, single colour, blank 3D printed keycap which cost you time, effort and inconvenience to print on your (relatively) expensive 3D printer and that pops off your board when you use it, but many wouldn't be, myself included.
I guess this is my point: 3D printing will not
replace molded mass manufactured plastics in any significant quantity, even if it is improved from it's current state. Making your own molds at home on your own affordable, accurate CNC machine, however, could. With a good CNC machine and a few other decent tools, there isn't much you can't make and the costs are dropping. That's why I think machines like the PocketNC are more exciting and "hype-worthy" than all these 3D printing devices.
It's the economy of scale. For some unique, individual pieces, it could be useful if they improve the materials and accuracy, though (like individual works of art, for instance), but then again, if you can machine them to greater accuracy from more durable materials for roughly the same cost, why bother.
It IS useful for rapidly prototyping through a few iterations of improvements of a product BEFORE using CNC to make molds, etc, though. Not so useful for a home user, but nice for a small startup. Again, if you are planning to CNC molds anyway, why pay the extra for a 3D printer when you can spend that on getting a better CNC machine and machine your prototypes using that.
I speak as a person considering a startup, prototyping parts and designing and redesigning a product before commiting to production. I'm building my own CNC machine, because I can, because the cost will be less than a 3D printer and because it will be the most useful to me. With a good machine you can mill replacement parts for practically anything. Cost to benefit ratio, just as you said.
