HAMAR LASER STEALTH Series, General Training Manual

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96
Calibration Checking Procedure
To ensure that a readout display accurately reflects changes in target position, perform the following
procedure.
1. Set the Readout Scale Switch
Set the Readout Scale Switch to the scale with the highest resolution (the .0001 in. setting).
2. Manually center and square the target to the oncoming laser beam
Make sure that the target is mounted in the target stand with the cable hanging down from the lowest
(6 o'clock) position on the target.
3. Mechanically center target with the micrometers on the target stand
Adjust the vertical axis first by turning the micrometer on the target stand until the vertical readout
display window reads 0.000. Be sure to center in such a way as to remove the micrometer backlash (if
you happen to turn the micrometer dial beyond the desired position, you will have to back the
micrometer off and, once again, approach the desired measurement). Complete the mechanical
centering by adjusting the horizontal axis micrometer control until the remaining readout display (R-
307) reads 0.000.
4. Read and record the micrometer settings (not the readout display)
Once the readout displays 0.000 (both windows on the R-307) the corresponding micrometer settings
should be noted on a worksheet (see Page 97 for a sample worksheet).
5. Turn the vertical axis micr.025 in. (one full turn)
Turn the vertical axis micrometer control one full revolution (+.025 in.). Be sure to eliminate
micrometer backlash.
6. Read and record the number on the vertical readout display window
Record the readout number on the worksheet.
Note: While adjusting only the vertical micrometer, watch both readout windows (on the R-307) for changes. If
the numbers in both windows change, the target will need to be rotated until it is square to the laser beam.
7. Re-zero the Display using both micrometers
Turn both micrometers until the readout display reads 0.000 in both axes.
8. Change the vertical axis micrometer -.025 in. (one full turn)
Turn the vertical axis micrometer control one full revolution (-.025 in.). Be sure to eliminate
micrometer backlash.
9. Read and record the number on the readout display
Record the readout number on the worksheet.
10. Re-zero the Display using the vertical micrometer
Turn the vertical micrometer until the readout display reads 0.000.
If your readout is a Model R-307, check the horizontal calibration.
11. Turn the horizontal axis micr.025 in. (one full turn)
Turn the horizontal axis micrometer control one full revolution (+.025 in.). Be sure to eliminate
micrometer backlash.
12. Read and record the number on the readout display
Record the readout number on the worksheet.
13. Re-zero the display using both micrometers
Turn both micrometers until the readout display reads 0.000 in both axes.
14. Change the horizontal axis micrometer -.025 in. (one full turn)
Turn the horizontal axis micrometer control one full revolution (-.025 in.). Be sure to eliminate
micrometer backlash.
15. Read and record the number on the readout display
Record the readout number on the worksheet. To calculate the percentage of error in the readout
display for a move of .025 in., see
Calculating Error in Calibration
on Page 96