Development is under way on the Plastruder MK5. Here is where we'll try to keep you updated on the progress.
We are attempting a remote-drive style extruder for the MK5. A remote-drive system involves separating the filament drive mechanism, such as the pinchwheel in the current design, from the rest of the extruder. This will allow us to stack more toolheads on a single printer. It also allows us to logically separate the filament drive system from the hot end much more easily.
(Status as of June 2010: in production! per Google Group msg from Zach)
Filament Drive System
Technology: Paxtruder based pinch wheel.
Charles Edward Pax shows a prototype of this system in the video below.
Lasercut Design
Status: Beta
Subversion: http://svn.makerbot.com/users/charles/bowden/
Pax is working on the design and the prototypes are looking good. It will be a filament mounted drive system with a remote hot end for maximum extrusion awesomeness. The same drive mechanism can be combined with a new mount, an MK4 and a few extra bolts to create a stand alone extruder for use in the CupCakeCNC.
A test was performed in which 4.5 lbs of ABS were driven through the drive mechanism proving it robust and reliable. The timing pulley marks in the filament were identical from beginning to end without. The varying marking depth indicative of an eccentric idler wheel were notably absent. Note: the filment was only driven through the drive mechanism and not extruded through a nozzle.
Drive Pulley
Status: Beta
Subversion: http://svn.makerbot.com/users/charles/bowden/drive-pulley.dxf
The first prototype worked great, but the pitch diameter was too large. The drawings have been modified and new prototypes are being tested. Preliminary results have been positive.
Hot End
PTFE Barrier
Status: Under Development
Subversion: http://svn.makerbot.com/users/hoeken/mk5-hot-end/
This will be a PTFE barrier that will screw into the nozzle with 1/8" NPT threads. Design needs to be made, checked, and prototyped.
Heater Block
Status: Under Development
Subversion: http://svn.makerbot.com/users/hoeken/mk5-hot-end/heater-block.dxf
An aluminum heater block that will have 4 mounting holes for M3 bolts. It will have mounting holes for 2 x 12.5W chassis mount power resistors (for heat) as well as mounting holes for a thermocouple. It will have 1/4" NPT threads for attaching the nozzle.
Nozzle
Status: Under Development
Subversion: http://svn.makerbot.com/users/hoeken/mk5-hot-end/
This will be an aluminum heater block that will be threaded 1/4" NPT on the outside and 1/8" NPT on the inside for maximum compatibility / hackability. Design needs to be created / tested and send off to production.
