Thermoplast Extruder Improvements
A good extruder is critical to proper 3D printing quality. There have been many people with problems with an unstable extruder.
High quality can be achieved by: 1. Keeping the flow rate of the extruder well controlled (proportional to XY movement speed, not necessarily constant) 2. A well shaped extruder tip. If the orifice (hole) is long and small this will restrict the flow and put pressure on the extruder. 3. Correct temperatures 4. XY movement resolution (not an extruder, but a cartesian bot challenge)
Here are some of the solutions I (Erik de Bruijn) came up with: 1. Nophead made a wonderful printable encoder system. To prevent a chicken and egg situation where you can't print an encoder wheel with an adequate quality and can't gain quality because you don't have one, I designed a wheel that could be printed on transparencies:
Here's the source code (it's pure SVG). Of course it is usable for other parts of a RepRap and other robotics projects than the RepRap... so go ahead. If you make one in a different resolution, please send it back and I'll update my pages as well.