Sub-Assembly Work - Printing in Plastic: Build Your Own 3D Printer - page 180

Figure 11-5. Enlarge one or two of the v-groove bearing holes so you can adjust them.
If you still can't get the two Strong-Tie rails securely seated between the v-groove bearings, you may
have to enlarge the holes under only one of the Strong-Tie rails. By enlarging these holes, you will give
the two bolts (used to hold the rail in place) more room to move, allowing the Strong-Tie rail to be
pushed into the v-groove bearings and securing it with additional bolts. Just make certain the rails are
perfectly parallel to one another or they will not move between the v-groove bearings smoothly.
Attaching the Upper Structural Sides
Once you have both the Z-Axis and Y-Axis rails moving smoothly on their v-groove bearings, it's time to
attach the Upper Structural Sides (Parts F and G). You will attach one side to each of the shorter edges of
Part H using two 1-1/2” bolts (1/4” diameter) and two barrel nuts.
Figure 11-6 shows one of the sides held against Part H in the location where it will be bolted. Notice
that the “arm” of the Upper Structural Side is pointing down towards the Z-Axis motor mount.