It seems to me they've ignored time in their cost equation. An injection mold can kick out dozens of widgets in a hour; how much time would it take for a 3D printer to print one widget? If your company needs several hundred widgets quickly, wouldn't this enter into your calculations?"At the same cost and quality, companies will always choose the flexibility of 3D printing over mass production. At the same cost and quality, 3D printing irreversibly overtakes conventional manufacturing as the preferred method of production."
I take it that you are assuming only one 3D printer. That won’t be the case when wonderful 3D printers are dirt cheap. Which is a necessary condition for 3D printers to deliver “the same cost and quality."The theory, I take it, is that the 3D printers will self-replicate, driving down their cost toward that of the “ink” it takes to manufacture them.
No, I assume any large facility would use multiple printers, but the 3D printer has to "draw" the widget and I don't see how that could possible be faster then molten plastic being shot into a mold and then kicked out as a finished piece. Don't get me wrong, I think 3D printers are fantastic and probably will dominate in many many areas; I just thought the article tried to make it sound like 3D printers will replace all the older production methods.
3D printers capable of working with metals will NEVER be "dirt cheap".
Crude devices extruding plastic and/or photopolymerizable polymer precursors are the only types that will ever be "dirt cheap".
3D printing will be used where it has advantages, just like every other technique of manufacture, but it is just another tool. All this hyperventilation about "3D printing will change the world" is just silly.
3D printing certainly offers many opportunities for improving things, but it is NOT a panacea.