Tighten both eccentric spacers an equal amount. These wheels will need very little tightening with
the spacer. TAKE VERY CAREFUL NOTE OF THE FOLLOWING, OR YOU WILL CAUSE YOURSELF A
PROBLEM LATER. DO NOT OVERTIGTHEN THE V WHEELS INTO THE V RAIL. THE V WHEELS ARE
MADE OF A VERY TOUGH PLASTIC (ACETAL OR POLYCARBONTE), BUT THEY WILL DEFORM IF
TIGTHENED TOO MUCH, LEAVING YOU WITH
CLUNKY MOTION WHICH WILL RESULT IN POOR
CUTS. SET THE TENSION SUCH THAT YOU CAN
DRIVE THE ENTIRE Y AXIS BEARING PLATE BY
ROLLING A WHEEL WITH YOUR FINGER BUT LOOSE
ENOUGH THAT THE WHEEL WILL SLIP IN THE RAIL
IF YOU LIGHTLY HOLD THE Y AXIS BEARING PLATE
WHILE YOU SPIN A WHEEL. Slide the bearing plate
back and forth to make sure that it glides
smoothly along the rail. If the wheels are too
tight, loosen the spacer a bit and recheck. Note
that, if over time, you find the wheels develop a
flat spot over time from being too tight, you can
loosen the wheel and it will move back to its
circular shape in a few hours.
Now find the back frame piece (the other long
rectangular piece). Slide the Y Axis Bearing Plates
that you just installed onto the rails all the way to
the Front Frame Piece. Hold the Back Frame Piece
upside down and cantilever the Front Frame Piece
and Y Axis Bearing Plates over the edge of your
table so the other side of the rail flushes up to the
Back Frame Piece. Slide an M5 washer onto a
self-
drilling screw and place it in the appropriate hole. If it’s snug in that hole, continue to turn it
through the Back Frame Piece until the drill point of the screw is sticking out. Slide the tip of that
screw into the center tap how of the V Rail. Do the same with the other rail. Grab the rail firmly
with your hand as you tighten. The torque of threading the screw tends to cause the rail to spin,
which you want to prevent. As you start to get good bite into the V rail with both screws, you can
set this assembly in its natural position (as it will be on the completed machine) in order to make
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