On 06/16/2013 04:24 AM, Erik Christiansen wrote: > current printer implementations just drag the spool > with the filament feed capstan
It's brutally simple: the filament drive hauls filament through a flexible tube that arches between a holder at the spool and the extruder, so the drive must overcome the tension required to unroll the spool plus the friction required to drag the filament: http://softsolder.com/2013/04/24/makergear-m2-filament-guide-tube-friction/ Bowden drives put the feed at the spool end of the guide tube, which makes retraction less effective. > a couple of microswitches The gotcha is that the filament loop thrashes around as the extruder head zips back and forth. On the M2, that's only along the X axis, but printers like the Ultimaker and Replicator move the extruder along both X and Y. I'm not sure where the sensor would be happiest, because you don't want to constrain the loop motion too much: pinning it to a board at the top of the arch might be too confining. -- Ed softsolder.com ------------------------------------------------------------------------------ This SF.net email is sponsored by Windows: Build for Windows Store. http://p.sf.net/sfu/windows-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
