I strongly believe that for at least the next 15 years at least, rapid prototyping will remain out of the home for all but the most dedicated of tinkerers (who are probably in engineering disciplines already). For the rest, occasional access to a commercial machine *may* be an option, but using the iPad as an example, the vast majority are more content to consume content than create it.

There is an issue I’ve seen raised several times over the use of RP tech in the jewellery field – that of individuals who do not have a grasp on the basic function of jewellery (being wearable, for the most part) creating elaborate designs using wax mills which then result in unusable pieces; without a grasp on the fundamentals of design, this is going to happen wherever “making stuff” has the hard work taken out of it.

I saw a rough draft of the ASTM standard for laser printed titanium a while back (actually engineers say additive manufacturing), so I think that will come out soon.

If you cast or machine something you don’t X-ray every component for cracks etc. Once a process is running you have to assume you have repeatability.

“There needs to be a standard format that is easy to print (a sort of PDF for 3D printers) and a way to share them”

The ASTM has developed this its called the additive manufacturing file format, at the moment its .STL, but they say this will kick in soon

http://en.wikipedia.org/wiki/Additive_Manufacturing_File_Format

If I have a blender I bought ages ago which is out of warranty, making a new part to fix it is a win for me, and a little skin off the nose of the vendor for charging too much for spares. However, if I have a Mercedes, fitting a part other than an official Mercedes one could have unfortunate knock-on effects if it isn’t a perfect reproduction of a standard one (I wouldn’t expect a 3D printer to have an X-ray attachment to check for cracks in printed output anytime soon, for example).

Ultimately, 3D printing ends up with Neal Stephenson’s “The Diamond Age” (admittedly, is in the same way that rocketry ends up in the kind of sci-fi Universe where space travel is commonplace, while remaining within the constraint of lightspeed). This may well be where the implicit connection between 3D printing and nanotech is coming from – as well as work on direct atomic manipulation by IBM and others.

I admit I can’t see a need for having a 3D printer myself, yet; I may find one in future. However, I remember when the easiest way to get something photocopied or faxed involved going to a corner shop; I happened to need a flatbed scanner for something a couple of months back, and found that a combined scanner-printer-copier-fax was cheaper at Staples than a standalone scanner. This gives me an opinion that one of the factors which will drive the cost of 3D printing down, is if it becomes a procedural component in some other process, as well as being a process in its own right.

I’m not a tech pioneer, but I *do* occasionally need things made that mass-manufacturing won’t provide, and which are cost-prohibitive to go the (otherwise economically-superior) dye/stamp route.

It took 20+ years for the golfball to be replaced by big expensive lasers, then cheap lasers, then expensive colour lases, then cheap colour lasers.

There is still big differentiation

Of course there would be the option for experts to use autocad or whatever produces the definition file to make their own things, but they would all be white plastic objects. There are a lot of those in your life.

A 3D printed part might be more expensive to make, perhaps $1 instead of $0.10, but I would have gotten my blender working again that day and for far less than I ended up spending. Printing parts, especially weak parts that are designed to go easily and early is a good sweet spot for the current state of the art in 3D printers.

Combined with a 3D scanner I can think of quite a few applications. Replacement parts for, well, anything that uses plastic parts. New bath plug. Fully functional silencer for a .22 – I doubt plastic would be strong enough for a bigger cartridge but it would definitely work for a .22. Of course it could also be used to create moulds with which to cast things from metal as well.

If I were the government it would be things like the latter 2 I would be worrying about. These are the areas where 3D printers would make it possible to procure things you’re not supposed to have.

A quote from a favourite SF author I’ve always liked:

“You know what your trouble is?” he says when we’re under the bridge, headed up to Fourth. “You’re the kind who always reads the handbook. Anything people build, any kind of technology, it’s going to have some specific purpose. It’s for doing something that somebody already understands. But if it’s new technology, it’ll open areas nobody’s ever thought of before. You read the manual, man, and you won’t play around with it, not the same way. And you get all funny when somebody else uses it to do something you never thought of. William Gibson – The Winter Market