Do it yourself. Almost.
Originally published 2005 in Atomic: Maximum Power Computing Last modified 03-Dec-2011.
Things are moving fast in the world of 3D printing.
"Rapid prototyping" ("solid freeform fabrication", to its friends) is reaching an interesting stage in its development. And it's a stage we've seen before.
There was a period, before the development of decent home photo printers, when you could already get top-quality prints of your digital files. Just not at home.
You sent your files to an output bureau (probably on 44Mb SyQuest cartridges; the first CD burners cost as much as a decent used car...), and they squirted 'em onto paper as big as you liked, for vaguely reasonable prices.
Output bureaux still exist, from the basic online photo printing services to specialist giant-print places for those times when nothing smaller than a billboard will do.
The photo-print places aren't terribly attractive now that we've got modern eight-cartridge ultra-long-print-life home photo printers (and some pretty impressive dye sublimation units, too), but if you want prints bigger than A3+ (a.k.a. "Super B", 13 by 19 inches), there's still a lot to be said for any option that doesn't involve filling a room and emptying your bank account by buying your very own Stylus Pro 9600.
We're in the same situation with rapid prototyping, except it's likely to last a lot longer. Even if money is no object for you, the number of kinds of "3D printer" out there mean that you're unlikely to want to spend the time to learn how to do every kind of rapid prototyping. It's not necessarily even just making parts; it can also involve putting them all together and delivering a final, working mechanism. Check out Pad2Pad, for instance. And eMachineShop, though they don't do assembly in-house yet. As soon as someone does, eBay stores will start getting a lot more interesting.
In The Beginning of "additive" 3D printing (as opposed to the old "subtractive" milling machines that cut a shape out of a block of source material), there were stereolithography machines, that UV-lasered a slowly growing resin prototype out of a bath of liquid, layer by layer. Now the big news in general purpose 3D printing is a similar layered arrangement, but using a fusible powder that gives more rapid printing with less fuss, and a more durable result. This is the same basic idea as was used by MIT's original 3D printing machines, but those machines used cornflour or plaster as the powder. Today's powder-printers (and their wire-fed competitors) can make objects that don't, um, fall apart in the rain.
There are even multi-powder printers, which can make parts of an assembly out of different materials (which can be electrically conductive...), and use low-melting-point filler powder so you can easily melt the supporting filler out of the finished part, instead of having to winkle it out of nooks and crannies by the use of dental picks, compressed air and profanity.
To make the output of these printers truly durable you need to work on it a bit more, though. There's good old casting, in which you make a mould from the part (destroying it in the process), pour in something tougher like molten metal, and then spend time cleaning up the result. And there's sintered-metal printing, where the printer produces a porous metal original which then gets dipped in some lower-melting-point metal to fill all of the pores. (And then you spend time cleaning up the result.)
Doing this can give results that could otherwise only have been made by elves (people have already, of course, made things that can't be made at all), but it's hardly suitable for a garage operation. And, for now, the same goes for every other really cool kind of rapid prototyping.
(Making signs with your very own computer-controlled vinyl cutter doesn't really count.)
Rapid prototyping output bureaux, though, will let us do this stuff at reasonable prices soon. Just like having your posters printed, or your memoirs vanity-published. Make up your own source file (or, more likely, download it from 0dayhardwarez.net), delete the circuit board text that says "10KW HERF GUN" and replace it with "AUNT EILEEN'S ROSE FUNGUS REDUCER", squirt it off to instafab.com.tw, wait for the package in the mail.
This, of course, will give various governments and big corporations conniptions, as modchips and pay TV stealers pop up like mushrooms all over the world, and every boutique gadget store creates its very own branded line of... whatever.
But all of the really bad grey-area devices I can think of - RF jammers of all kinds, for instance, and remote bomb triggers - are simple enough that any bright teenager can knock one up on veroboard today. And the prototypers probably won't accept plans that are obviously for a Gatling gun.
The up side of all this, for people who aren't interested in breaking any laws worse than the ones that make VCRs functionally illegal in Australia (PDF), will be easy access to far, far more wonderful toys.
You decide.