Thursday, May 29, 2008

RepRap: Big step up in print quality!

This posting on the RepRap blog shows the massive progress these guys have made recently in their printing quality. The progression is clearly visible in this photo of some door handles. The most recent incarnation is the work of a guy known as "Nophead", with his own blog describing his work. His machine uses a RepRap extruder on a purchased CNC table rather than the RepRap 3D platform, which made me think that the RepRap platform must be the reason for the less-than-commercial-grade print quality. I asked him about this in a comment, and he replied that the improvements were:
  • his extruder has a shaft encoder to control the speed precisely
  • he has temperature control to +/- 3C
  • he doesn't have any comms delays (I don't know the architecture well enough to know exactly what he means here)
  • he runs his head faster so as to stretch the filament down to 0.5mm.
  • careful choice of printing material
To conclude, he says "All these things can be sorted out on Darwin [the current RepRap prototype] so I expect its prints to be this good in a month or two." That's a very cool thing. It's wonderful to see such progress.

Within just a year or two, RepRap will be much further along in terms of both quality and ease of use, and it will be affordable for small clubs in high schools and colleges all over the world, and large numbers of individual hobbyists. By then it will probably print multiple materials including conductive ones, so you'll be able to embed circuitry in a widget. Today one of the big killer apps for 3D printers is little action figures based on avatars from Second Life and similar games, but when 3D printers really are ubiquitous, people will move on to far more interesting apps that I can hardly imagine.

Let me not forget this very nice list of a lot of different commercial and hobbyist 3D printers.

Still waiting for my CNC mill platform, the eBay fellow has been getting a huge volume of business and his shop is a bit swamped. I've been getting a bit more organized with the electronics, including resuscitating an old FX2 board design, and I've ordered some stepper motor driver parts that should arrive soon.

Wednesday, May 7, 2008

Affordable CNC gadgets

CNC has existed as a hobbyist pursuit much longer than 3D printers have been. I finally broke down and purchased one of these on eBay. It will take a couple weeks to arrive, and the one I got did not include stepper motors, couplers, or motor drive electronics. Those are things I'd enjoy doing myself anyway, so no problem.

I like this project which is along similar lines.

For my own gadget, I need to order stepper motors, think about couplers, and start planning how the electronics will go together. I'm thinking about being lazy and using the parallel port.

I got to see a real RepRap up close!

This evening I went to a presentation and demonstration of a real live RepRap by Bruce Wattendorf and his son. It was very cool to meet somebody who's built a real one and is totally up to speed on every aspect of the project. I asked some questions about the long-term future of the RepRap project.
  • Can they get much better spatial resolution without compromising the social goal of serving the developing world? Yes: better spatial resolutions can be gotten with finer nozzles, which would print slower. You could build a duel-nozzle gadget with a wide nozzle for fast clumsy printing, and a narrow fine nozzle for slow elegant finishing.
  • Will they bump into patent problems as they move toward the state of the art currently occupied by commercial 3D printers? A number of patents will expire in about three years and the RepRap guys will then be much freer in this area.
He wrapped up his presentation by showing the nanofactory video, "Productive Nanosystems: from Molecules to Superproducts". I came to 3D printers from an interest in nanotech, and he came to nanotech from working on 3D printers. It was gratifying to see that the similarity is clear to people on the other side of the fence.

It was a heck of a lot of fun. I took some pictures. Bruce also has many more pictures on his blog. Interestingly, the parts that are normally plastic in a RepRap are made of wood in Bruce's machine, and he's in the process of printing a set of plastic parts.

Bruce's talk was sponsored by a group called DC401, a bunch of Rhode Island folks who enjoy going to DefCon. They are working with a woman in real estate to arrange a lab space in a building in downtown Providence where they can do electronic and mechanical tinkering. It was fascinating to hear her talk about how she's making it all work by using the other floors for businesses and residential space. This reminds me a lot of MITERS, and it warms my heart.