Bibo enhanced bed clamps

Redesigned bed clamps for the Bibo2 Laser Touch X (and similar) printers-- easier to assemble than originals, and hold heat bed and glass more firmly together as well. Included in the print are bolt covers for the opposite contact points of the glass bed, as well as some simple bed clips for custom bed fastening.

Assemble as in photos, or refer to post-printing instructions for details.

Printed in PLA these are good for bed temps of about 75 C or below. As @VladimirKHV mentions, these will fail at higher (80+ C) bed temperatures. As shown in photos, my white PLA clamps eventually deformed at higher bed temps. They still did a good job for quite some time at 60C bed temp.

My clamps printed using PETG with 100% infill (in photo printed w/red PETG, on Amazon http://a.co/hhiR7aS) will hopefully withstand higher temps.

Version 2 changes:
- reinforcement around top clamp mounting hole to reduce deformation at higher bed temps.
- Bottom clamp hole for threading screw has new