Da Vinci 78mm rear spool holder

EDIT: I was still getting some tangling with this spool holder. Sideways spool holders lend themselves from separating from the back of the printer, and then occasionally if the print head moves all the way to the front, and then all the way to the back, the released tension will cause the filament to wrap around the holder.

I'm still going to leave the files up, but I'd strongly recommend moving to either of these straight-feed holders:

http://www.thingiverse.com/thing:722110

or

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