TB 9-5210-207-24
Table 2. Minimum Specifications of Equipment Required
Minimum use
Manufacturer and model
Common name
specifications
(part number)
GAGE BLOCK SETS
Range: 1 to 42 in.
7901372
Accuracy: Grade AS-1
7901961
7915946
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 table 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.
7. Equipment Setup
a. Prepare a clean work area and allow equipment and TI to stabilize at room
temperature for 1 hour.
b. Observe that the TI is free of nicks and burrs.
c. Gently push and pull the TI micrometer head laterally to insure that there is no
excessive backlash in the threads. If backlash is indicated, refer to paragraph 8 b below.
8. Micrometer Head Calibration
a. Performance Check
(1) Select the appropriate gage blocks required to verify the range of the TI from
gage block set.
(2) Assemble the gage blocks as shown in figure 5. Each stack of gage blocks must
have an inside caliper jaw at each end of the gage blocks to serve as end stops for the TI.
The gage blocks and end stops must be firmly wrung together and secured with the tie rods
supplied with the gage block set.