Depends on how big your extruder barrel. We used to specify #31 AWG. In recent times, however, we've been looking at much longer lengths of glass insulated nichrome from Pelican Wire in heavier gauges like #27-28. The longer lengths lower the temperature on the surface of the nichrome and keep the insulation from perishing. I put together a Rapman 3 extruder head with #28 {7 ohms} and Kaptonby Forrest Higgs - Reprappers
Acrylic? It's pretty brittle, but it's used in laser cut versions of Darwin with fair success.by Forrest Higgs - Mechanics
I'm currently trying to use Kapton after some indifferent results with fire cement. I think you see the fire cement solution and the kapton tape solution both in use largely because we don't have enough operating hours on either yet to know which method, if either, is clearly superior. I think the issue will sort itself out in the next year or two.by Forrest Higgs - Mechanics
GeertB Wrote: ------------------------------------------------------- > The 624 bearings are $99 per 100, see > . > That's pretty cheap. Now, if only MakerBot would > carry Mendel hardware packages... They'd have the > volumes to get prices down to reasonable levels. > I think they're too far into Makerbot to do that kind of switch at this point. Nothing to stop you from doingby Forrest Higgs - Mechanics
bo190e Wrote: ------------------------------------------------------- > Does the RepRap Mendel and the MakerBot machines > share all electronics or are there differences. > > Makerbot och Mendel använda samma Generation 3 elektronik. Jag misstänker dock att BitsFromBytes styrkort kan lätt anpassas till det. Vore det så skulle jag bara köpa en Rapman från BitsFromBytes och använda deby Forrest Higgs - Reprappers
Nope! Would love to see the formulae behind the model.by Forrest Higgs - Reprappers
Needles are cheap, if you can legally purchase them. Here in California if you go into a chemists and try to buy one they will just about call the police unless you have a doctor's prescription. Doctors are very hesitant to prescribe them for non-medical uses. This is bizarre in that the California gov't provides clean needles free to people using illegal drugs. That said, you can go to the vby Forrest Higgs - Mechanics
jbayless Wrote: ------------------------------------------------------- > I wonder how the economics would be if they were > to switch to a full mass-production model > (injection molding, etc). I think it has always been understood that you could mass produce a Reprap machine considerably cheaper than you could locally produce one. The question for me has always been whether the mass-by Forrest Higgs - Reprappers
I recently started working seriously with Mathematica 7 and am also building up a BitsFromBytes Rapman. In that a lot is known about the operating characteristics of the Rapman I decided to see if I could calculate what it would cost to run one. Assumptions: ABS filament - $9/lb Rapman built out - $1500 Duty cycle - 50% Service life - 36 months Interest rate - 10% Capital Recovery Factorby Forrest Higgs - Reprappers
Have two written in VB.NET 2005 and VB.NET 2008 Express. The VB.NET 2008 Express one is under development and is by far the more promising. :-)by Forrest Higgs - General
I think you're probably in pretty good shape with the firmware as long as you are using NEMA steppers and belts. The extruder firmware code could be a problem what with BitsFromBytes use of a threaded rod driven extruder when everybody else is using pinch wheels.by Forrest Higgs - General
unfold Wrote: ------------------------------------------------------- > OK, the BfB electronics kit is not the same as the > Gen 3 RepRap electronics. Its a completely > standalone solution. Totally separate solutions. And, it appears, quite a good one.by Forrest Higgs - General
I frankly don't see that situation changing any time soon. From what I've heard, Makerbot is selling the Cupcake printer as fast as they can make them. That makes keeping extra controller kits for repstrappers a bit of a difficult situation.by Forrest Higgs - General
I checked the Cotronics 989FS ceramic adhesive that I bought last year and discovered that it had really gone off. Having a shelf life of 6 months, this was not surprising. I checked with Cotronics and discovered that they now retail quite a few of their products through McMaster-Carr in the US. Danny at Cotronics recommended this one... After having had a bad experience with fire cement onby Forrest Higgs - RepRap Host
Tolerances for large projects are rarely as close as you find for CNC apps. A long-time rule of thumb in house construction, for example, is that if your stud wall positioning is okay as long as they are within 4-6 inches of where they are supposed to be as long as the errors are consistent. Builders know that people can simply not see differences that small in room dimensions. Mind, ceiling hby Forrest Higgs - General
It isn't. It's getting to the point where a couple of variations on that theme are going to get made and tested. That's all.by Forrest Higgs - Reprappers
I don't expect HP to change it's business model any time soon.by Forrest Higgs - General
I found several references to such a printer on the web. It's apparently something back in the labs at HP and not yet ready to be mass-produced. Plan on the filament costing you a fortune, if previous HP business models with their inkjet printers are any guide.by Forrest Higgs - General
by Forrest Higgs - Tissue Engineering
I'm building the bitsfrombytes Rapman kit just now. It's pretty good so far.by Forrest Higgs - General
VDX Wrote: ------------------------------------------------------ > > So it's a much more complex task than "simple > print with two or more toolheads" ... > So were "simple prints"by Forrest Higgs - Tissue Engineering
You don't know you history, obviously. Bird droppings were used directly as the main ingredient in medieval gunpowder. If ever you wondered why people built dovecotes, it wasn't just for fertilizer. Oddly, the Wikipedia entry doesn't wonder why peasants weren't allowed to build them. Stupid gets. :-pby Forrest Higgs - General
All you're doing is working on a rationale for denying people tools. The coercive, authoritarian state that is in the making these days is perfectively capable of trying to destroy Reprap without Reprappers showing them how.by Forrest Higgs - General
Reprap is about building things, not destroying things.by Forrest Higgs - General
You can easily carry that through to the US. Ten years ago about half the students in computer science were women. Now, virtually no women are studying computer science. They pretty much migrated into law from CS. Ask yourself, do lawyers do anything productive or do they just get in everybody's way on behalf of people with money to hire them?by Forrest Higgs - General