What are the best cardstock printers?

There are 3D printers, there are 3D printers that print 3D printers, there could be 3D printers that print 3D printers that print 3D printers, but could there be 3D printers that print 3D printers that print 3D printers that print 3D printers?

• After two recursions, this seems to reduce to nonsense. In other words, it seems like these are equivalent: "3D printers that print 3D printers that print 3D printers" and "3D printers that print 3D printers that print 3D printers that print 3D printers", unless of course the 3D printers that each 3D printer was printing were all different, and the final 3D printer could only print "apples".

• Answer:

  This question is being asked in a pretty silly way... let's give it a serious answer.  On July 17th of 2014, as I write this, just how close are we to this goal? What remains to be done, and how far away from it are we? You are probably already aware of http://www.reprap.org: the project aimed at building a self-replicating rapid prototyping system or 3D printer. The RepRap project is, arguably, directly responsible for the rapidly growing and proliferating consumer 3D printer market today. It is certainly the direct progenitor of Makerbot. Right now, the commonly built RepRap printers are able to produce only one significant portion of themselves: The frame structure. To save on costs and replication time, the many variants of the project include frame materials that aren't 3D printed - but variants like the http://www.tantillus.org demonstrate this is convenience, not necessity. By using nontraditional motion control methods, some versions of RepRap have done away with tradtionally manufactured passive motion control components like bearings and rails: The http://reprap.org/wiki/GUS_Simpsonis a delta-platform RepRap using 3D-printed arms to translate motor input to extruder motion. That's not an insignificant progression towards replication: With some more design work, there's no reason to believe that an inexpensive 3D printer could reproduce all its own mechanical and structural components. So, what else do we need to be able to make to get a working 3D printer out of another 3D printers? Electronics, of course. We need to make circuit boards and motors. Well, no one is selling a real, commercial solution that can 3D print circuits... but they are very, very close. Leaving aside some limited success with printing low-temperature metals into prepared traces, the most promising options right now seem to involve conductive inks - http://www.rabbitproto.com/ is developing a toolhead and printer for prosumer-level enthusiasts;  http://www.nscrypt.com/ has done some demonstrations combining their industrial microdispensing platforms with thermoplastic extrusion (I first found out about this in person at Rapid 2014 and was extremely impressed). Based on the progress I've seen, I would be shocked if there was not a viable option for a 3D printer that can embed conductive elements in the next 12 months. With a pick-and-place tool to add in integrated circuit packages, that means we're just about done. Getting usable motors is going to take some more time after we have conductive elements, but should not be insurmountable. Chttp://www.designboom.com/technology/cornell-researchers-3d-print-a-fully-functional-loudspeaker-12-16-2013/d a working speaker last year - a motor is a couple orders of magnitude more difficult but does not contain any novel components or structures we don't already know how to process with 3D printing.