BOLT 1087931 - Caterpillar

The 6V7899 Size Setting Fixture Group can be used to check or calibrate the 6V7898 Dial Bore Gauge Group. See Special Instruction Form SMHS8253 for information on how to use this dial bore gauge.
This is a precision instrument. Always be careful when using the setting fixture to prevent damage and/or loss of adjustment to the setting fixture. Always use the procedure shown in this instruction to adjust the setting fixture. Make sure all parts are the same temperature during the calibration procedure.
Components Of The 6V7899 Size Setting Fixture Group
1 - Storage Case. 2 - Master Standard (for checking accuracy of fixture).3 - Setting Fixture.4 - Magnifier.5 - Anti-rust Compound.6 - Setting Standard, 50-75 mm Range.7 - Setting Standard, 75-100 mm Range.8 - Setting Standard, 100-125 mm Range.9 - Setting Standard, 125-150 mm Range.10 - Setting Standard, 150-175 mm Range.11 - Hex Wrench.12 - Spanner Wrench.13 - Adapter Plate -- For use when Setting Early Style Dial Bore Gauge (has "Made in England" Stamped on Extension Sleeve).Using The 6V7899 Size Setting Fixture Group
1 The following procedure shows how to calibrate 6V7898 Dial Bore Gauge (1) with size setting fixture (2). It is not necessary to remove fixture (2) from the storage case; however, if it is removed, do not lift the fixture by micrometer head (A).2 Find the correct setting standard for the diameter size to be checked. For example, if the gauge is to be set to 78.468 mm, the correct setting standard is marked 75.000 + mm. Clean both ends of the setting standard, the V-block and micrometer spindle tip (B). Be sure spindle lock (C) is loose to permit the micrometer to turn freely. 3 Set the micrometer head to the size desired, and lightly tighten spindle lock (C). For example, if the gauge is to be set to 78.468 mm, set the micrometer head to 3.468 mm.4 Put the correct setting standard in the V-block against the micrometer spindle tip. Install the correct gauge point (3) as far as it will go into the dial bore gauge. Carefully put dial bore gauge (1), with gauge point, in the nest of the size setting fixture.5 Loosen gauge point (3) until it touches the setting standard (D) and the dial indicator hand moves.6 With zero (0) on the dial indicator face at approximately the 12 o'clock position (or the position where it is easiest to read) adjust gauge point (3) until the hand of the dial indicator is approximately at zero position. (Do not hold the gauge during this procedure -- the fixture will keep the gauge in a stable position). Tighten gauge point lock nut (4) to hold the gauge point in the adjusted position. 7 Move the gauge back and forth in the horizontal plane until the dial indicator hand shows the "most minus" (-) reading. Move the gauge back and forth in the vertical plane until the dial indicator hand shows the "most minus" (-) reading. Adjust the dial face as necessary to