Well, a traditional non-temperature-controlled kiln does not heat uniformly, leading to slightly deformed part, or a part you can't fit threaded rod through. Fortunately, it shouldn't be too hard to hard to make a temperature controlled electric kiln using nichrome and fire brick.by Gene Hacker - Mechanics
People aren't going to be interested in pirating copyrighted or patented products, yeah right. It's going to happen eventually I guarantee it. Just look at papercraft: You mean it is legal to scan a product and 3d print it?by Gene Hacker - General
Not to mention that lead free low melting point alloys tend to be expensive.by Gene Hacker - General
The stratasys insulation foam appears to be fairly thick and fragile: So apparently material shrinkage might be an issueby Gene Hacker - Plastic Extruder Working Group
Well, if your gonna have a vacuum, why not do electron beam melting. It's like laser sintering, but with electrons. If you can do electron beam melting, it might be possible to have a lot less moving parts. It might even be possible to highly focus the electron beam to etch chips. In fact, electron microscope can easily be converted into electron beam lithography machines with a simple attachby Gene Hacker - General
Are you suggesting a microscopic reprap?by Gene Hacker - General
Are you suggesting a microscopic reprap?by Gene Hacker - General
Hey, if you could find a way to massively etch hair on the small scale, you can set up structures to selectively reflect certain wavelengths of light using destructive interference. Sorta like morphos butterfly scales. Not to mention the possibility of using it to etch chips, like the semiconductor industry already does(except they use masks instead of a controlled ion beam). Only problem is thby Gene Hacker - General
Or send them to a junkyard and periodically resupply microchips.by Gene Hacker - Mechanics
I just found this interesting video of a Hexapod drawing with a pen, which the robot's creator intends to replace with a CNC routing head. This is pretty much a subtractive reprap, considering that it draws one of its own parts in the video. Having a reprap capable of moving itself presents some interesting possibilities, namely that it is capable of having infinite tool heads without a complexby Gene Hacker - Mechanics
Well, there is only one problem I see with PLA, it's biodegradable. A while back, Mercedes started putting wires with biodegradable insulation. As time passed the insulation degraded and caused shorts which caused engine failure. Speaking of PLA, the local grocery stores have just now started to sell food in containers made of it. So if anyone wants to try some PLA extrusion tests, try your locby Gene Hacker - Plastic Extruder Working Group
I am talking about printing out technical ceramics, which require a bit more than just fire and dirt. And apparently, small electric pottery kilns can be converted to make high grade technical ceramics(superconductors), so I guess this solves the problem. Heres some information on making high temperature superconductors, for all who are interested in the specialized processes needed for techniby Gene Hacker - Paste Extrusion Working Group
Your kidding me! High frequency piezoelectric actuators are the most expensive part needed for metallic extrusion! There is only one problem with ceramics, they need to be fired in a specially controlled kiln.by Gene Hacker - Paste Extrusion Working Group
Hey, if you can adjust the pore size to really small, you could print out water filters. Maybe even reverse osmosis filters. Well, from watching some cooking shows, I just learned that pasta is more like a gel then a granular media.by Gene Hacker - Paste Extrusion Working Group
Almost forgot, does anyone know any ceramic formulations?by Gene Hacker - Paste Extrusion Working Group
The thing with pasta dough is it is only good as a support material. You can't make a engine with pasta dough. But, extruding pasta dough demonstrates that you can extrude granular media with a syringe extruder. Maybe something in the dough makes it easier to extrude? Reprap really needs to extrude true ceramics, as reprap is currently having melting problems. Just think of when reprap startsby Gene Hacker - Paste Extrusion Working Group
Hey, why not just do what the MIT fab lab people do and just use cheap off the shelf atmel microcontrollers? Speaking of FPGAs, I heard about some super-FPGAs awhile back that could reconfigure in milliseconds or less.by Gene Hacker - General
Well my school has a semiconductor fab, it takes up a garage sized room. It would be awesome to have something that does the same and fits on a table top. Did I mention the hydrofluoric acid(eats away glass) bath used to etch the chips and that its not automated? It also uses normal visible light halogen lights to expose the chips(old hand-me-down apparatus from local semi-industries). The hardby Gene Hacker - General
You know, you can cupric sulfate onto a metal and get a copper plating? If your looking for copper sulfate, try a garden store, it is commonly used as an algaecide for small ponds. Maybe instead of putting down expensive conductive ink why not put down copper powder and plate it together?by Gene Hacker - Plastic Extruder Working Group
You don't need steel balls, and in fact steel balls are not fit for the job. Steel corrodes, so use something that dosen't corrode, like bits of rock or ceramic. I will post my ball mill design as soon as I get a chance.by Gene Hacker - Polymer Working Group
On the circle closing and the start and stop look, that was due to air bubbles in syringe. Some of the first layers actually turned out to be remarkably smooth. The blob is where I lifted the extruder off. The indentation on the side of one of the extrusions was due a "bump" when I was taking the picture. But I do see your point on pneumatic extruders. As for syringe extruders, it also might bby Gene Hacker - Polymer Working Group