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Using the Nova Comet II Wood Lathe:
The Variable-Speed DC (Direct Current) Motor
The DC motor contains brushes that contact the commutator. It is very important to
allow between 30 to 45 minutes of 'run-in' time of these brushes before any turning or significant
load is applied. This should be done in the higher rpm range. A clicking or swishing noise in the
motor is normal which will reduce as the brushes wear in. During normal operation, 5 minutes of
warm-up may also be required on cold weather days.
The motor is one of the most important elements in the lathe. The Comet II Wood Lathe uses a high
quality and powerful DC motor to provide the best turning performance. It has been pre-wired in such a
way that it allows the lathe spindle to rotate in a counter-clockwise direction when facing the spindle.
We use a Permanent Magnet DC Motor (PMDC) which produces the most torque for conventional motors.
The motor is nominally rated at 3/4 HP (550watts), however, can produce a higher output.
Belt and Variable Speed Range:
Coupled with the high torque DC motor, we also use a 3-step pulley to provide optimum power bands.
The label on the controller displays the ranges as 1, 2 and 3. With the unit facing the operator, Band 1
is the left most drive-belt position for the slower turning. Band 2 is in the middle and Band 3 on the
right.
Speed Band Type of Work
RPM Range
1
Slow Speed:
Large faceplate and spindle work.
250
– 680
2
Medium speed:
Small faceplate and smaller diameter spindle work.
530
– 1420
3
Fast speed:
Small turning and miniature turning work.
1380
– 4000
The Controller also has
approximate speeds in
relation to the speed
control Knob for each
belt setting
The speed range is achieved with a Variable Speed Controller. A micro-processor chip, in conjunction
with other electronic components, allows the input power to be manipulated. In return, smooth
Variable DC power can be delivered from the controller to the motor.
This is a Y-Type Appliance where all electrical workings and attachments are NOT to be altered,
replaced or worked on. Any work in this area is to be done by TEKNATOOL International Only. Please
contact Teknatool International should any damage to the electrical components occur.
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