TB 9-5210-217-24
5. Accessories Required. The accessories required for this calibration are common
usage accessories, issued as indicated in paragraph 4 above, and are not listed in this
calibration procedure.
CALIBRATION PROCESS
6. Preliminary Instructions
a. The instructions outlined in paragraphs 6 and 7 are preparatory to the calibration
process. Personnel should become familiar with the entire bulletin before beginning the
calibration.
b. Items of equipment used in this procedure are referenced within the text by common
name as listed in tables 2.
c. Unless otherwise specified, verify the result of each test and, whenever the test
requirement is not met, take corrective action before continuing with the calibration.
Adjustments required to calibrate the TI are included in this procedure. Additional
maintenance information is contained in the manufacturers' manuals for this TI.
d. Unless otherwise specified, all controls and control settings refer to the TI.
7. Equipment Setup
a. Remove TI from protective case.
b. Visually inspect TI for any damage that will affect the accuracy of measurement.
c. Exercise TI several times along full length of range to determine if roughness,
binding, or irregularities occur.
d. If necessary, clean thimble and spindle.
e. Ensure setting rings are clean and free of debris.
8. Bore/Hole Diameter Indication
a. Performance Check
(1) Place Gage Ring on surface plate.
(2) Set TI to a smaller size of the Gage Ring to be used prior to inserting TI into
setting ring.
(3) Ensure that the TI is vertical with all of its sensing probes, or feet, in contact
with the inner diameter of the setting ring.
(4) Rotate the TI in the Gage Ring to obtain a minimum indication on the TI
dial indicator.
(5) Ensure TI measuring arm is retracted prior to being withdrawn from Gage Ring.
(6) Repeat technique of (1) through (5) above using Gage Ring sizes and TI ranges
listed in table 3. TI will indicate within tolerance. If TI does not indicate within tolerance,
perform b below.
