Using the Nova Mercury Lathe
The Variable Speed DC 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
mornings.
The motor is one of the most important elements in the lathe. The Mercury lathe uses a high
quality and powerful DC (direct current) motor to provide the best turning characteristics. It
has been wired in such a way that 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 1/2 Hp (180watts) but can produce a higher output than this.
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.
Optimal Speeds on Each Band
Speed
Band
Type of Work
RPM
Range
1
Slower Speed Range:
Larger faceplate & spindle work
140-1750
2
Medium Speed Range:
Small faceplate work (up to 5") & smaller diameter
spindle work
320-3670
3
Fast Speed Range:
Small turning & miniature turning work
470-5350
Total Speed Ranges Available
Belt
Step
1
2
3
RPM
Slow
Medium
Fast
140
320
470
200
510
760
510
1170
1780
810
1780
2770
1110
2400
3650
1430
3000
4600
1640
3570
5000
1750
3670
5350
The speed ranges are achieved with a variable speed controller. A microprocessor chip in conjunction with
other electronic components allows the input power to be manipulated. In return smooth variable DC power c
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 workings occur.
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