Makerbot’s MK5 Plastruder is a significant improvement to the previous MK4. The new model is designed for reliablity, low maintenance, and ease of use. They have completely redesigned the heating element, barrel, and nozzle to make the extruder as long-lasting as possible. In comparison with the MK4, the components screw more tightly together, and the tool is smaller in general. The resistors in the heating element heat very evenly and provide a very consistent temperature. The new filament guide system and drive gear have been redesigned to produce a much greater push strength and a smoother slide than the MK4. The new tool can extrude smoothly for extended periods of time.
I have redesigned this tool so that it can be powered by a snap motor by JrKerr. In order to accomplish this, it was necessary to turn the entire assembly upside down so that the filament moves downward during printing. The filament now runs alongside the right side of the drive shaft instead of the left as in Makerbot’s version. All the acrylic plates have been modified, and the tool now includes top and back plates so that it fits on a standard Fab@Home tool mount. The Plastruder needs to be heated to 230 degrees, and it sits at just the right distance from the build base, which is heated to 100 degrees. Once calibrated correctly, the tool can be used in almost the same way as the MK4 was on the Fab@Home, and will produce ABS models with a high level of accuracy.
Thermoplastic Tool on the wiki page: http://fabathome.org/wiki/index.php/Fab%40Home:Tools#Thermoplastic_tool
Pictures, DXF files, and assembly instructions on Thingiverse: http://www.thingiverse.com/thing:4892
I have just completed the design of a vacuum attachment for the Dremel Tool holder. Before, it was often awkward to hold and maneuver a vacuum hose while milling a piece of foam or wood. Now, the holder can house an attachment for a Shop-Vac (for ease of vacuuming dust that results from milling). I found an attachment that is just the right size and provides the right amount of suction for gathering the dust of the materials commonly milled on the fabber. It can be purchased along with a set of other attachments here: http://www.shopvac.com/shopvac-accessories/Products/1-14-Micro-Cleaning-...
The vacuum attachment fits onto the end of a standard Shop-Vac hose and easily slides into the right side of the Dremel tool holder. It was a little tricky to get the correct size of the two holes and the height between the two side pieces projecting from the right side of the holder. As it is now, the attachment sits just low enough to provide enough suction, and just high enough as to not interfere with the piece sitting on the platform.