asciilifeform: although Bell Labs was denied the patent on the basis of his prior art.

asciilifeform: TLDR: an obscure German fellow almost certainly had working transistors in the '20s.

asciilifeform: "...a paper, JVST A Volume 20, Issue 4, pp. 1365-1368 describing transistors made with anodized aluminum gate insulator and a chemical bath deposited semiconductor (CdS/CdSe). Both are techniques that do not require complicated equipment (beaker, current source, heater) and should have been accessible in the 1920s."

asciilifeform: "in 1995 R. G. Arns found a 1948 legal deposition by Johnson which said the opposite: that Bell Labs back then had a project to test Lilienfeld's transistors, and before Johnson took over the project,"

asciilifeform: mostly useless for semiconductor work, though

asciilifeform: benkay: one can trivially build an STM out of junkyard parts: http://www.e-basteln.de/index_m.htm

asciilifeform: I'm more interested in the ion beam deposition approach, rather than optical masks, though

asciilifeform: (granted the latter gives you LSI at best, 1970s level)

asciilifeform: no, you get the SAWs from the uni junkyard

asciilifeform: Kerr cell for toggling

asciilifeform: although I do have access to university surplus lab junk.

asciilifeform: btw, I am personally researching a means for fabricating 1980s-level VLSI in "bush conditions." No prizes for guessing why. But I cannot promise that anything will come of it.

asciilifeform: astronomical tooling cost

asciilifeform: mircea_popescu: do you own a chip fab? does it fit in your house? why, or why not? using the term "printing" for photomask fabrication is disingenuous.

asciilifeform: I can see the political virtues of reviving the skills of building 18th century muskets, but 3d printers aren't usefully in the mix.

asciilifeform: producing crude but working small arms is trivial. modern ammunition, not so much.

asciilifeform: contrary to popular delusion, the fist of the State will come down in the future not on guns, but on ammunition.

asciilifeform: mircea_popescu: if you want to go the whole hog, dispense with cartridges. fire nails or ball bearings, with injected gasoline for the propellant.

asciilifeform: btw, I personally have a design for a 3d printer which prints solid steel. think "TIG welder" plus XYZ frame. but this would be ruinously expensive to run, and would burn down the house of the first idiot who builds on in his garage. so, unpublished.

asciilifeform: my point wasn't that it is physically impossible to make small arms out of garbage (it is possible) but that a 3d printer gains you nothing compared to using parts straight from the junkyard.

asciilifeform: if you don't need many shots, even this works: http://en.wikipedia.org/wiki/Leather_cannon

asciilifeform: did you really suggest guar gum or the like?

asciilifeform: mircea_popescu: look up the temperature of the inside of a barrel (of the smallest pistol) after one shot.

asciilifeform: if all you want is 17th century tech, you can easily make single-shot pistol or shotgun from hardware store pipes. and it will be far more reliable (and deadly to the enemy, vs. the user) than anything you can get out of a $3k 3d printer.

asciilifeform: mircea_popescu: yes, sintering. even in the USSR, they had it.

asciilifeform: 3d printers are being touted by idiots as "we can now produce modern arms in our basement without knowing any machining." which is patently false, and is likely to remain so.

asciilifeform: mircea_popescu: if you can produce a polymer which reliably stays in one piece in the form of a rifled barrel, you can become a far, far richer man than you already are.

asciilifeform: for those who have never seen an AR, the "lower" is simply a small can which holds the trigger/hammer mechanism, with the stock screwing into one end and the bold carrier/barrel assembly (known as the "upper") into the other end.

asciilifeform: inhies: exactly. hence the 3d printer folks interest in the AR.

asciilifeform: hardness is not the only issue. (temperature is another.)

asciilifeform: mircea_popescu: find me a polymer which can be used to produce a barrel reliably firing modern calibers. I know people who will pay very serious moneys for such.

asciilifeform: so you can buy the entire metal portion of a Glock, for example (barrel and striker mechanism) with no paperwork, as if it were a video card. because the SN is stamped on an aluminum plate embedded in the lower, plastic portion.

asciilifeform: in the U.S., the part which legally counts as "the gun" is the piece with the serial number on it.

asciilifeform: mircea_popescu: it may help to know that the focus on the AR is solely because of a weird quirk of U.S. law

asciilifeform: a CNC mill is infinitely more useful in practice. but it doesn't have the same sexy appeal to noobs who think they can produce arbitrary widgets just by hitting a button (actually false for both solid printing and cnc)

asciilifeform: if 3d printers actually were what their enthusiasts imagine them to be (a substitute for industrial production) rather than machines for churning out brittle crap, the same dynamic would apply here.

asciilifeform: mircea_popescu: if someone found a way to "fix" the atrociously-inefficient RuBisCO enzyme, you could feed a family on what you can grow in a flower vase.

asciilifeform: cads: the way I understand it, the main virtue of 3d printing is that you can build the thing in your basement out of junkyard parts and not give a rat's arse about patents or copyrights.