8
PM-30MV v3 2020-10
Copyright © 2020 Quality Machine Tools, LLC
MOTOR CONTROLS
Before doing anything, check the installation in-
structions in Section 1
•
Connect the mill to a 220Vac outlet.
•
Press and release the green Power
ON
button to energize
the control circuit; the tachometer should light. This is a
self-latching circuit – when the
ON
button is released, a
contactor in the electrical box maintains power until re-
leased by the red
OFF
button (also a momentary switch).
•
The round orange E-stop button, right, is in series with
the
OFF
button. Like the
OFF
button it de-energizes the
control circuit completely, but it should be used only for
its intended purpose – emergency disconnect. Once the
E-stop button is pushed in, it stays in until twisted
firmly
clockwise
to release.
•
Also in series with the Power and E-stop buttons is a mi-
croswitch actuated by the acrylic Chip Guard in front of the
spindle. The motor will not run if the chip guard is open.
•
The spindle motor is controlled by a three position switch,
Forward
F
- Stop
O
- Reverse
R
, and a continuously-vari-
able speed control knob.
F
= Forward (clockwise, looking down on workpiece, used
for most milling and drilling
O
= Stop
R
= Reverse (counter clockwise, looking down)
Figure 3-1
Motor controls
Figure 3-2
Belt adjustment
SPINDLE SPEEDS
The PM-30MV is a belt-driven machine with two speed ranges,
(
L
) 50-1500 rpm and (
H
)1400-3000 rpm.
To select a speed range, disconnect power, then remove the
blue motor cover (4 screws). Loosen the socket head screws
on each side of the motor, then swing the motor forward to free
the belt, Figure 3-2. Make sure that the ribbed belt is prop-
erly engaged with the selected pair of grooved pulleys, then
re-tighten. Before powering up, rotate the spindle by hand to
check tracking and tightness of the belt. Do not over-tighten –
aim for ± ¼” slack between the motor and spindle pulleys.
Excessive cutter noise, chatter, poor finish and
tool wear are often the result of too high a feed
rate, and/or too high a spindle speed. If unsure,
go slow!
Section 3 USING THE MILL