Graber I3 4 linear bearing table

Tired of seeing the front left side of my print bed vibrating, and with one linear bearing to spare, I decided to conceive this design. It uses 4 LM8UU bearings, instead of the original 3, to hold the Y axis table. Provides a more stable and rigid structure for printing.

Based on larger version designed by Alex Borro: http://www.thingiverse.com/AlexBorro/designs