Service Home How To Procedures Spindle Drive Belt - Tension Adjustment - Gates Sonic Meter - Mill
Last updated: 10/24/2024

Spindle Drive Belt - Tension Adjustment - Gates Sonic Meter - Mill

Spindle Drive Belt - Tension Adjustment - Gates Sonic Meter

1

Change the units to lbf, as follows:

  • With the unit powered off, hold [0] and [9] and push [POWER] at the same time [1]. The unit will turn on with the current units displayed. 
  • Push [SELECT]until the display shows lbf.
  • Hold [POWER] until the power goes off.
  • Push [POWER] again to start the meter in normal operation.

To display frequency in Hz, push [HZ] [2] repeatedly until the display shows Hz [3].

2

Push [MASS] [1]. 

Reference the VMC spindle belt tension specification for updated belt tension values and settings.

Enter the correct value from the Mass, Width, and Spans column in the table from the reference above. For example, if you have a 40-Taper, Transmission, and 7500 RPM, push this sequence: 0, 0, 4, 7. This sets the value to 4.7.

VMC - Spindle Drive Belt - Tension Adjustment - Gates Sonic Meter

This procedure tells you how to use a Gates 508C or 550 sonic tension meter to correctly adjust the tension in the spindle drive belt of a VMC. The illustrations show a VF-series mill, but the procedure is the same for the VM and Toolroom mills.

Tools Required:

  • For 40-taper spindles: Belt Tension Tool 40 T (T-1488)
  • For 50-taper spindles: Belt Tension Tool 50 T ( (T-1805)

1

Loosen the (4) screws for the plate that holds the motor.

Attach the belt tension tool on the head casting.

Tighten the belt tension tool against the plate that holds the motor. Do this until the belt has tension.

Use you hand to tighten (4) screws for the plate.

2

Attach the sensor cable to the Gates sonic tension meter.

Push this button sequence on the Gates sonic tension meter:

  1. Push [POWER].
  2. Push [MEASURE].

Place the sensor approximately 3/8 in (1 cm) away from the belt. Quickly pull your finger across the edge of the belt ("Pluck" the belt like a guitar string). Do not let the sensor touch the belt.

 Note: If you cannot make the necessary vibration with your finger, you can tap the belt with the handle of a screwdriver.

3

Compare the "Tension" value from the table to the value on the meter.

If the tension is too low, use the belt tension tool to tighten the belt.

If the tension is too high, use the belt tension tool to loosen the belt.

Measure the tension again, and make adjustments until the belt tension is correct.

Torque the (4) screws [1] to 50 ft-lb (68 Nm).

Remove the belt tension tool.

Office Mill - Spindle Drive Belt - Tension Adjustment - Gates Sonic Meter

1

Loosen the (4) motor mount screws [1].

Push the motor mount plate away from the spindle until there is tension in the belt.

Use your hand to tighten the (4) motor mount screws [1].

2

Attach the sensor cable to the Gates sonic tension meter.

Push this button sequence on the Gates sonic tension meter:

  1. Push [POWER].
  2. Push [MEASURE].

Place the sensor approximately 3/8 in (1 cm) away from the belt. Quickly pull your finger across the edge of the belt ("Pluck" the belt like a guitar string). Do not let the sensor touch the belt.

 Note: If you cannot make the necessary vibration with your finger, you can tap the belt with the handle of a screwdriver.

3

Compare the "Tension" value from the table to the value on the meter.

If the tension is too low, push the motor mount plate away from the spindle.

If the tension too high, push the motor mount plate to the spindle.

Measure the tension again, and make adjustments until the belt tension is correct.

Torque the motor mount screws to 30 ft-lb (40.7 Nm).

HMC - Spindle Drive Belt - Tension Adjustment - Gates Sonic Meter

This procedure tells you how to use a Gates 508C or 550 sonic tension meter to correctly adjust the tension in the spindle drive belt on a horizontal mill. This procedure is shown on an EC-1600. The procedure is the same for other horizontal mills.

Tools Required:

  • 24" (610 mm) socket extension
  • Scissor jack
  • Block of wood, approximately 2" x 4" x 6" (51 x 102 x 152 mm)

1

Loosen the (4) motor mount screws [1].

 Note: The view in the illustration is from the front, from above the spindle head casting.

2

Push [EMERGENCY STOP].

Put a scissor jack [1] in the bottom of the column casting.

Put a 2" x 4" x 6" (51 x 102 x 152 mm) piece of wood [2] on top of the jack.

Release the [EMERGENCY STOP].

Jog the Z Axis down until the bottom of the transmission is approximately 1" (25 mm) above the wood.

Push [EMERGENCY STOP].

Put the jack directly below the oil sump [3].

Release the [EMERGENCY STOP].

Push [0.0001/1.].

Jog the Z Axis down until the wood cannot be moved.

Push [EMERGENCY STOP].

3

Attach the sensor cable to the Gates sonic tension meter.

Push this button sequence on the Gates sonic tension meter:

  1. Push [POWER].
  2. Push [MEASURE].

Open the plate under the spindle to get access to the belt.

Place the sensor approximately 3/8 in (1 cm) away from the belt. Quickly pull your finger across the edge of the belt ("Pluck" the belt like a guitar string). Do not let the sensor touch the belt.

 Note: If you cannot make the necessary vibration with your finger, you can tap the belt with the handle of a screwdriver.

4

Compare the "Tension" value from the table to the value on the meter.

If the tension is too low, increase the height of the scissor jack.

If the tension is too high, decrease the height of the scissor jack.

Measure the tension again. Make adjustments until the belt tension is correct.

5

Use a torque wrench [1] to tighten the (4) motor mount screws [2] to 50 ft-lb (67 Nm). Use a torque wrench [1] to tighten the (4) motor mount screws [2] to 50 ft-lb (67 Nm).

Use a 24" (610 mm) socket extension to reach the lower screws.

 Note: The view in the illustration is from the front, looking down over the spindle head casting. The tool release piston has been removed.