A re-designed UP! Extruder Feeder/Cable Tray design. Removing the roller bearing and housing and replacing with spring steel guide element. This gives greater flexibility in filament thickness diameter, along with the added simplicity of design. Includes a fitting for air line supply to cool the extruder gear.
Version 2 has been released with fittings for two 50mm fans (to suit heatsinks) and adjusted filament outlet and air line positions to minimise mis-feeds.
New files below, and am keeping the originals for those who don't want to add a fan.
Buy an Artline felt pen (this is an Australian brand pen with a steel pocket clip - see here http://www.pelikanartline.com.au/index.php?option=com_content_ex&view=category&layout=multi-view&id=69&Itemid=154 )and remove the steel clip from the lid.
Print out, clear all holes and guides and install pen clip as shown. Install onto servo motor, and ensure the clip clears the gear.
Reinstall onto printer, and extrude!
You may need to adjust the size of the outlet guide hole if your spool curls too much (only open it up a little).
This is a prototype design, but has been tested to work with some pretty bad filament!
See the thread for more info: http://www.pp3dp.com/forum/viewtopic.php?f=3&p=5646&sid=6f128c7472db717e051d901921f69eeb#p5646