The trim pot (it’s next to the enable pin) is
adjusted using a small Phillips screwdriver. You
have to be VERY
careful taking readings. It’s
easy to short things if you get sloppy with your
lead placement. Put your black lead on the
screw that tightened down the ground wire
(black wire) on the power connector to the CNC
shield. Place the red lead on the trim pot itself.
Pull the leads off and adjust. You can also
alligator clip from your red lead to your
screwdriver to more easily dial in the setting.
Clockwise reduces the voltage,
counterclockwise increases. Be advised that
these potentiometers can “loop back around.”
You need to get a reading of 0.60 Volts. You could go as low as 0.55 volts or as high as 0.62 volts,
but 0.60 Volts is your target. Do this for each driver.
Now, power things back completely off by unplugging your power supply from the wall and
the USB cable from your computer.
Grab the wires from your Z Motor (the one mounted at the top of the X Axis Bearing Plate) and
trap them using the included wire staple. You need to drive the nail into the Left Frame Piece
with a hammer. Put this staple on the left frame piece, about one inch (about 25mm) further
back than the V rail mounting holes. Make sure the wires are under the retainer or the
connector at the end of the wires will not fit
through it if you just hammer in the
retainer first.
Run the X and Y Motor cables underneath the
machine. Notice that where the bottom of
your frame pieces have half circles cut out at
the very bottom of the pieces. These are for
running the wires. Run them through and loop
the cord around the threaded rods running
through the bottom of the frame (only
applicable if you ordered the rigidity upgrade)
a couple of times to take up some extra wire.
Wrap them as shown below.
Now, with everything STILL POWERED OFF,
plug in the motors. The stepper motor shield
(red electronics board labels each axis. Notice
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