Service manual

1
Y-Gantry Replacement
The Y-gantry assembly may be replaced in the event of damage or premature wear to
the steel bearing tracks. The Y-gantry assembly consists of:
- Aluminum extrusion with 2 steel-rod tracks
- Top and bottom reversing units (top unit with notched shaft)
- Y-axis bearing cart assembly
- Y-axis main drive belt (clear)
- 4 mounting bolts and T-nuts, and 1 captive T-nut on left side of extrusion
A new large-diameter pulley (# 12-828), and motor mounting plate may be used, instead
of transferring them from the original gantry. This will facilitate the repair procedure, and
assure that all hardware is compatible.
Follow the procedural steps below in sequence to maintain the squaring alignment as
much as possible.
1) Shut down the machine normally, and disconnect the main air hose from the rear of
the machine.
2) Remove the Y-axis motor housing from the top of the gantry assembly. Remove all
four mounting screws with either a 1/8” Allen wrench or a 5/16” nut driver or wrench.
3) Manually move the gantry to the approximate center of the machine. Mount an angle
bracket on each side of both top and bottom X-axis bearing carts: Insert spring-
loaded T-nuts into the frame extrusions, and tighten the flat-head bolts securely with
a 5mm Allen wrench. Make sure there is no left-to-right movement of the gantry
possible once the four brackets are locked in place.