Re Dan Graves' original Youtube link -
This is a Z Corp 3D printer
http://www.zcorp.com/en/home.aspx. It works by depositing a thin layer of powder (typically corn starch or plaster 10 years ago, maybe other materials now) on a platen, then using an inkjet print head to print an image of the lowest layer right on the powder. The ink causes the powder to stick together where it's wetted. Then the platen is lowered a small amount (maybe .004" or so), a new layer of powder deposited, and the next layer printed, etc. etc.
Once the part is completely printed, and as shown on the video, you pull the object out of the powder and blow off excess powder.
What they don't show is that the part is
not very strong at this point. So you either saturate it with cyanoacrylate (super glue) or lower it into molten wax. This adds strength. Then you can safely handle the part and sort-of use it ... but the part will
never be as strong as metal! You'll notice that they don't really reef down too hard on the nut they're using as a "test" in the video. Also, if you carefully compare the printed wrench to the original, you'll note that they've made some changes to the shape of the worm - giving it more strength and allowing it to will work more smoothly with the rough surfaces involved. Impressive, nonetheless.
One of Z Corp's big claims to fame, of course, is that you can produce authentically colored objects. This can be very valuable when evaluating the "look and feel" of something like a new shampoo bottle. You can even give the appearance of the label! And I believe the 0.004" resolution of their top-of-the-line printer is better than that of melt-and-squeeze 3D printers. IIRC, the laser hardening/liquid based machines have the best resolution.
I was able to use a Z Corp 3D printer about 10 years ago, while an engineer at HP's inkjet production/R&D division in Corvallis, OR. At the time, Z Corp was using HP's inkjet print heads, and HP was working with them on optimization, etc. We were encouraged to do "G-job" projects, as well as work related stuff on the printer, so that a wide variety of capabilities could be thoroughly tested. My own "G-job" was a section of bathroom cabinetry I was rebuilding for a friend. Good, clean fun!
Of course, Z Corp's products have continued to advance since I worked with them (~2002) and since the video was produced (~2011 or a bit earlier).
- hman
(John Herrmann)
