You're probably right, but keep in mind that mass production imposes some costs of its own. There are the up-front costs you allude to when you say "short-run" --- even if you're cutting your mold from aluminum, that's an expensive way to make five instances --- but there are also costs associated with the "mass" nature of the production.
First, mass production must be geographically centralized. This means you have shipping costs. For fragile or bulky objects, the shipping cost can sometimes exceed the material cost.
Second, mass production involves inventory at every stage of the supply chain, although you can cut inventory down quite a lot from what we used to do 60 years ago. Maintaining inventory is expensive.
So it's possible that 3-D printers will beat molding for mass production. It's just not likely in the foreseeable future.
Molecular nanotechnology will, of course, make 3-D printers beat molding.
> Molecular nanotechnology will, of course, make 3-D printers beat molding.
It will?
Fiction and facts don't mix in the same discussion, molecular nanotechnology if it will ever be a reality will possibly make 3-D printers beat molding.
Injection molding is very fast, extremely cheap and can be used for very large runs. We do not know any of those parameters for nanotech yet assuming that we can can actually implement it.
Well, I didn't mean to imply that it was a certainty that MNT would exist, and of course it's possible for it to exist but only in some limited form, with limits we can't easily predict today. So you are correct: everything about it is uncertain.
On the other hand, it seems very likely that at some point we'll have flexibly programmable universal assemblers capable of relatively rapid self-reproduction (say, less than three months) and of making materials at least as strong as the cheap thermoplastics we use in injection molding out of relatively common elements. There are a lot of different avenues that could get us to that goal.
The intrinsic cost of making something consists, as I understand it, of amortized capital costs, marginal raw material costs, marginal energy costs, and marginal labor. Self-reproducing assemblers eliminate the physical part of the capital costs; automated manufacturing of any kind eliminates marginal labor, leaving only the labor component of the capital costs; and the raw material and energy costs probably will be about the same for artificial molecular assemblers as they are for natural ones such as potatoes.
The labor component of the capital cost is simply the R&D required to automate the making of the thing. It seems very likely to me that this will be similar to what we do today for injection molding, a guy building 3-D models in a CAD/CAM system, but with much less in the way of concerns about taper and the like.
I recognize that you know a great deal more about modern manufacturing than I do, so if I am wrong about something, please do not hesitate to correct me.
>Molecular nanotechnology will, of course, make 3-D printers beat molding.
Why bother with the nanotech when you can buy a flute in a 4D immersive environment and use it via a haptic interface (with feedback) that to your brain is no different than using a regular flute. Oh and it costs equivalent of an iPhone app and an orchestra comes bundled with the flute.
Why bother with the intermediation/illusion of an 4D immersive environment when you can have a richer/more nuanced experience playing a "real" flute. ;)
I'm going to guess that there are a lot of people that would use a holodeck if they had one, why bother if you can live real life?
If you've got a 4D immersive environment on hand then why bother buying a real flute? If you can't tell the difference I mean. In the case of the flute you could have the best flute in the world [for you], break it and it doesn't need fixing just re-rendering, the pads wouldn't wear out, you could alter the weight/tone/colour/taste at will, you could play along with an orchestra without the trouble of hiring one etc.. VR theoretically will give as far more nuance than real life.
First, mass production must be geographically centralized. This means you have shipping costs. For fragile or bulky objects, the shipping cost can sometimes exceed the material cost.
Second, mass production involves inventory at every stage of the supply chain, although you can cut inventory down quite a lot from what we used to do 60 years ago. Maintaining inventory is expensive.
So it's possible that 3-D printers will beat molding for mass production. It's just not likely in the foreseeable future.
Molecular nanotechnology will, of course, make 3-D printers beat molding.