TECHNICAL MANUAL CALIBRATION PROCEDURE FOR GAGE BLOCKS MECHANICAL COMPARISON. This publication replaces T.O. 33K dated 30 December 2013.

Transcription

1 TECHNICAL MANUAL CALIBRATION PROCEDURE FOR GAGE BLOCKS MECHANICAL COMPARISON This publication replaces T.O. 33K dated 30 December Distribution Statement C - Distribution authorized to U. S. Government agencies and their contractors for official use or for administrative or operational purposes only, 30 November Requests for this document shall be referred to AFMETCAL, 813 Irving-Wick Dr W, Heath, OH Destruction Notice - For unclassified, limited documents, destroy by any method that will prevent disclosure of the contents or reconstruction of the document. Published under Authority of the Secretary of the Air Force 30 AUGUST 2014

2 LIST OF EFFECTIVE PAGES INSERT LATEST CHANGED PAGES. DESTROY SUPERSEDED PAGES. : The portion of the tet and illustrations affected by the changes is indicated by a vertical line in the outer margins of the page. Date of issue for original and changed pages are: Original August 2014 TOTAL NUMBER OF PAGES IN THIS PUBLICATION IS 26, CONSISTING OF THE FOLLOWING: Page * Change Page * Change Page * Change No. No. No. No. No. No. Title...0 A A A-2 Blank...0 B B-2 Blank...0 C C-2 Blank...0 *Zero in this column indicates an original page A USAF

3 GAGE BLOCKS MECHANICAL COMPARISON 1 CALIBRATION DESCRIPTION: Table 1. Test Instrument (TI) Performance Test Characteristics Specifications Method Gage Blocks: to 4 in (0.20 to mm) (w) Length Accuracy of 12 in from stated value Flatness Range: to in Flatness not measured (0.20 to 2.50 mm) Accuracy: Not Measured Range: to 4 in Flatness measured using an (2.50 to 100 mm) Inspection Interferometer Accuracy: 6 in TIR Parallelism Range: to 4 in Parallelism measured using a (0.20 to 100 mm) Gage Block Comparator Gage Blocks: to 4 in (0.20 to mm) (w) Length Accuracy of 20 in from stated value Accuracy: 6 in TIR Flatness Range: to in Flatness not measured (0.20 to 2.50 mm) Accuracy: Not Measured Range: to 4 in Flatness measured using an (2.50 to 100 mm) Inspection Interferometer Accuracy: 12 in TIR Parallelism Range: to 4 in Parallelism measured using a (0.20 to 100 mm) Gage Block Comparator Accuracy: 12 in TIR 1

4 Table 1. (Cont.) Test Instrument (TI) Performance Test Characteristics Specifications Method Gage Blocks: 5 to 20 in (125 to 500 mm) (w) Length Accuracy of 2 in/in from stated value Flatness and Parallelism Range: 5 to 6 in Flatness measured using an (125 to 150 mm) Inspection Interferometer Parallelism Measured using Accuracy: 5 in TIR a Gage Block Comparator Gage Blocks: 5 to 20 in (125 to 500 mm) (w) Length Accuracy of 3 in/in from stated value Range: >6 to 10 in (>150 to 250 mm) Accuracy: 6 in TIR Range: >10 to 12 in (>250 to 300 mm) Accuracy: 7 in TIR Range: >12 to 16 in (>300 to 400 mm) Accuracy: 8 in TIR Range: >16 to 20 in (>400 to 500 mm) Accuracy: 10 in TIR Flatness and Parallelism Range: 5 to 6 in (125 to 150 mm) Accuracy: 8 in TIR Range: >6 to 10 in (>150 to 250 mm) Accuracy: 10 in TIR 2

5 Table 1. (Cont.) Test Instrument (TI) Performance Test Characteristics Specifications Method Gage Blocks: 5 to 20 in (125 to 500 mm) (w) Length Accuracy of 3 in/in from stated value (Cont.) Flatness and Parallelism Range: >10 to 12 in Flatness measured using an (Cont.) (>250 to 300 mm) Inspection Interferometer Parallelism Measured using Accuracy: 10 in TIR a Gage Block Comparator Gage Blocks: 5 to 20 in (125 to 500 mm) (w) Length Accuracy of 5 in/in from stated value Range: >12 to 16 in (>300 to 400 mm) Accuracy: 12 in TIR Range: >16 to 20 in (>400 to 500 mm) Accuracy: 14 in TIR Flatness and Parallelism Range: 5 to 6 in (125 to 150 mm) Accuracy: 16 in TIR Range: >6 to 10 in (>150 to 250 mm) Accuracy: 18 in TIR Range: >10 to 12 in (>250 to 300 mm) Accuracy: 20 in TIR Range: >12 to 16 in (>300 to 400 mm) Accuracy: 20 in TIR Range: >16 to 20 in (>400 to 500 mm) Accuracy: 24 in TIR 3

6 Table 1. (Cont.) Test Instrument (TI) Performance Test Characteristics Specifications Method Gage Block Accessories Flatness measured using an Flatness and Parallelism Inspection Interferometer Parallelism measured using Triangular Base Range: N/A a Gage Block Comparator (All) or an Electronic Height Accuracy: Flatness and Gage and Surface Plate Parallelism not to eceed 12 in TIR Half Round Jaw Range: N/A Accuracy: Flatness, not to eceed 12 in TIR Straight Jaw Range: N/A Accuracy: Flatness and Parallelism not to eceed 12 in TIR Center Point Range: N/A Accuracy: not certified Scriber Point Range: N/A Accuracy: not certified 2 EQUIPMENT REQUIREMENTS: Minimum Use Calibration Sub- Noun Specifications Equipment Item 2.1 GAGE BLOCK Range: to 4 in Mahr Federal Mahr Federal COMPARATOR 130B B-24 Accuracy: 1 in/ in * SOFTWARE Range: N/A T.O. 33K PACKAGE Accuracy: N/A 2.2 GAGE BLOCK SET Range: to 4 in L.S. Starrett Co. Mitutoyo Accuracy: 6 in from stated value See footnotes at end of Equipment Requirements. 4

7 Minimum Use Calibration Sub- Noun Specifications Equipment Item 2.3 GAGE BLOCK Range: 5 to 20 in Mahr Federal Mahr Federal COMPARATOR 130B-58AF 130B-16 Accuracy: 1 in/ in * 2, * SOFTWARE Range: N/A T.O. 33K PACKAGE Accuracy: N/A 2.4 GAGE BLOCK SET Range: 5 to 20 in L.S. Starrett Co. 8 Accuracy: 1 in/in from stated value * 2, * LABMASTER Range: 0 to 4 in Pratt & Whitney UNIVERSAL U Accuracy: 4 μin * 4, * 5, * SOFTWARE Range: N/A T.O. 33K PACKAGE Accuracy: N/A 2.6 GAGE BLOCK Range: 0.2 to 1 in Mitutoyo SET 5 Accuracy: not to eceed 2 μin from stated value Range: 2 to 4 in Accuracy: ( L) µin from stated value, where L = length in inches * 6, * INSPECTION Range: Length, 20 in Davidson INTERFEROMETER D Accuracy: 3 in TIR * 8, * 9, * SURFACE PLATE Range: in GGG-P-463 Accuracy: Grade A * ELECTRONIC Range: in Federal HEIGHT GAGE EAS-1226 Accuracy: 1 div * ALCOHOL-ETHYL Range: N/A As Available (200 PROOF) Accuracy: N/A See footnotes at end of Equipment Requirements. 5

8 Minimum Use Calibration Sub- Noun Specifications Equipment Item 2.11 SOAK PLATE Range: N/A As Available Accuracy: N/A 2.12 ARKANSAS STONE Range: N/A As Available Accuracy: N/A 2.13 DEBURRING STONE Range: N/A As Available Accuracy: N/A 2.14 PRESERVATIVE Range: N/A As Available Accuracy: N/A * 1 The accuracy specification 1µin/ inch is equivalent to the accuracies identified T.O. 33K * 2 For the Length Calibration of Gage Block sizes 5 to 20 inches (125 to 500 mm) (w) Length Accuracy of 2 in/in from stated value, the combined TAR of (2.3) and (2.4) is 2.1:1. * 3 For the Length Calibration of Gage Block sizes 5 to 20 inches (125 to 500 mm) (w) Length Accuracy of 3 in/in from stated value, the combined TAR of (2.3) and (2.4) is 3.1:1. * 4 Only used to measure non-standard Gage Block sizes. * 5 Accuracy calculated using AFCAV uncertainty calculations using Gage Block Set (2.6). * 6 See step 3.8. * 7 For setup and referencing the Labmaster Universal only. * 8 For the Flatness Calibration of Gage Block sizes to 4 inches (2.50 to 100 mm) (w) Length Accuracy of 12 in from stated value, the TAR is 2:1. * 9 For the Flatness Calibration of Gage Block sizes 5 to 20 inches (125 to 500 mm) (w) Length Accuracy of 2 in/in from stated value, the TAR is 1.7:1. * 10 For the Flatness Calibration of Gage Block sizes 5 to 20 inches (125 to 500 mm) (w) Length Accuracy of 3 in/in from stated value, the TAR is 2.7:1. * 11 For Parallelism Calibration of the Triangular Base with offset step, the combined TAR of (2.8) and (2.9) is 2:1. 3 PRELIMINARY OPERATIONS: 3.1 Review and become familiar with the entire procedure before beginning the Calibration Process. WARNING Unless otherwise designated, and prior to beginning the Calibration Process, ensure that all test equipment voltage and/or current outputs are set to zero (0) or turned off, where applicable. Ensure that all equipment switches are set to the proper position before making connections or applying power. If not strictly observed, could result in injury to, or death of, personnel or long term health hazards. 6

9 WARNING Alcohol is an eye and skin irritant. Use protective equipment (chemical splash goggles and gloves) where potential of splash and skin contact may occur. Failure to do so may result in injury. If eye contact should occur, flush well with water and seek immediate medical attention. If not strictly observed, could result in injury to, or death of, personnel or long term health hazards. WARNING Alcohol is a flammable liquid and may be ignited by heat, sparks, or flames. Vapors may travel to a source of ignition and flash back. Alcohol burns with an almost invisible flame. If not strictly observed, could result in injury to, or death of, personnel or long term health hazards. m = micrometers µin = microinch 1 µin = in 1 µin = mm 1 µin = µm 1 µm = mm 3.2 This Calibration Process is for Gage Blocks that will be certified with one of the following Length Accuracies identified below or Length Accuracy identified in AFCAV. Certification documentation for all Gage Block Sets or individual Gage Blocks will include one of the Length Accuracies identified below. All Gage Blocks within the set will be certified with the same Length Accuracy. Gage Blocks within the set that do not meet the assigned Length Accuracy must be replaced/repaired or identified on the Report of Measurement as not certified. A replacement/repair agreement should be established between the PMEL and owning organizations. Nominal Gage Block Length: to 4 inches Length Accuracy: 12 in from stated value Length Accuracy: 20 in from stated value Nominal Gage Block Length: 5 to 20 inches Length Accuracy: 2 in/in from stated value Length Accuracy: 3 in/in from stated value Length Accuracy: 5 in/in from stated value The Length Accuracy to be assigned to the Gage Block Set or individual Gage Block can be determined by the Flatness and Parallelism measurement results, owner/user requirements or original manufacturer specifications, whichever is applicable. Some Gage Block Sets or individual Gage Blocks may have labels and/or manufacturing documentation identifying the accuracy as Grade 3, AS-1 or AS-2. In all cases, Gage Blocks identified to be calibrated using this calibration procedure must be calibrated and certified to one of the Length Accuracies in Table 1. 7

10 3.3 For individual Gage Blocks: The Limited Certification Label will be annotated with the Gage Block Serial Number, Certified Deviation from Nominal Length and Accuracy to which the Gage Block is certified For Gage Block Sets: The Limited Certification Label will be annotated with the Length Accuracy to which the entire Gage Block Set (TI) is certified. All Gage Blocks within the set must be certified with the same Length Accuracy. If some Gage Blocks within the set do not meet the Length Accuracy, the Gage Block(s) must be repaired/replaced or identified on the Report of Measurement as not being certified. Refer to Appendi A eample, generate a Report of Measurement that identifies the following TI Gage Block Set information: If the software generated calibration documentation does not provide all required information, it may be necessary to develop and provide a cover page. Part Number (Model Number) Date of Calibration Gage Block Material Nominal Lengths Serial Numbers Measured/Calculated deviations from nominal Accuracy Laboratory Environment Gage Blocks that are missing and/or not certified Meaning of plus (+) and minus (-) associated with the deviations from nominal length Accessory Accuracy Accessory Description Accessory Serial Numbers Accessories that are missing and/or not certified 3.4 All certified Gage Blocks within a set must be manufactured from the same material. All Gage Blocks manufactured from a different material than the rest of the set must be replaced or identified on the Report of Measurement as not being certified. 3.5 For unanswered questions concerning equipment, software, instructions and specifications, refer to applicable manuals. 3.6 All Gage Blocks must be serialized. Serialization must be accomplished by laser or acid etching IAW with manufacturer specifications. 3.7 Ensure that the appropriate AFPSL Certificate of Calibration is available to obtain the deviations from nominal size (corrections) for all Master Gage Blocks being used. 3.8 For non-standard Gage Blocks: TIs that are manufactured to non-standard Gage Block lengths can be calibrated using the Gage Block Comparator or the Labmaster Universal. Non-standard Gage Blocks up to 4 inches in length can be certified to Length Accuracies of 12 or 20 µin. Non-standard Gage Blocks larger than 4 inches in length can only be certified to Length Accuracies of 3 in/in or 5 in/in When using the Gage Block Comparator to calibrate non-standard Gage Block lengths: No more than two AFPSL certified Gage Blocks (2.2) can be wrung together to create a single Master Gage Block nearly the same length as the TI. Calculate the actual length or deviation from nominal using certified deviations as documented on the AFPSL Certificate of Calibration. TAR using this measurement process is 1.9: When using the Labmaster Universal to calibrate non-standard Gage Block lengths: Measure Flatness following para 4.1 and measure Parallelism following para 4.2. Measure the length of the Gage Block following para 4.5. The Datum and Scale Factor must be standardized using AFPSL certified Gage Blocks (2.6). Calculate the actual length or deviation from nominal using certified deviations as documented on the AFPSL Certificate of Calibration. TAR using this measurement process is 1.6:1. 8

11 3.9 All TIs must be in the laboratory environment a minimum of 8 hours prior to making any measurements The TI measured/calculated deviation from nominal length is accomplished using the Gage Block Comparator and comparing the TI to a Master Gage Block. It is recommended the TI and the Master Gage Block be manufactured from the same material The precision wringing surfaces on the TI will be referred to as the face Refer to Figure 1 for location of gaging point. The gaging point on a square TI with the nominal length etched on the face is located halfway between the hole and the right edge adjacent to the etched side. TI GAGING POINT TI GAGING POINT TI NOMINAL SIZE TI GAGING POINT TI NOMINAL SIZE Figure Initially clean all TIs and case with a degreasing solution. The final cleaning of the TIs must be done using Alcohol-Ethyl and wipe dry Perform only those portions of the Calibration Process, which pertain to the TI being calibrated When using Gage Block Comparator (2.1) and (2.3), verify that T.O. 33K is the most recent version per the AF TO Catalog or equivalent When using Lab Master Universal (2.5), verify that T.O. 33K is the most recent version per the AF TO Catalog or equivalent. 4 CALIBRATION PROCESS: Unless otherwise specified, verify the results of each test and take corrective action whenever the test requirement is not met, before proceeding. 4.1 FLATNESS CALIBRATION: (Using the Inspection Interferometer) Use the Inspection Interferometer to inspect both faces on each TI for raised burrs, scratches and other surface defects. Raised surfaces must be removed. Damage at the gaging point is cause for replacement. Fan is a function of surface flatness and is only measured if present. The measured flatness error and fan error are not combined. 9

12 4.1.2 Refer to Figure 2 and use the Inspection Interferometer to measure the Flatness and/or Fan in two aes of both faces for each TI. Replace TIs that eceed the Table 1 specifications for the tolerance of the TI set. TI FRINGE PATTERN TI FRINGE PATTERN A B C B A A= Fringe Deviation B= 1 Fringe (1/2 Wavelength) C= Fan Deviation Eample Flatness Calculation: A= Fringe Deviation, about 1/4 of B B= 11.7 in (1/2 Wavelength Inspection interferometer) Flatness Error = 2.9 in For Gage Block with Fan. Fan Fringes are not parallel Measure Fan using B and C. Eample Fan Calculation: B= 11.7 in (1/2 Wavelength Inspection Interferometer) C= Fan Deviation = 1/3 of B Fan Error = 3.9 in 4.2 PARALLELISM CALIBRATION: Figure For all TIs up to 4 inches in length: When measuring Parallelism using the short Gage Block Comparator (2.1). Gage on the TI and measure the parallelism error between the two faces at a minimum of five positions (near each corner and the gaging point). The difference between the smallest and largest observed indications from the measured positions must not eceed the specifications listed in Table 1. Replace TIs that eceed the Table 1 specifications for the tolerance of the TI set For all TIs 5 inches to and including 20 inches: When measuring Parallelism using long Gage Block Comparator (2.3) that is equipped with movable anvil/crank assembly. Place the TI on the movable anvil and adjust the crank until the TI is under the Gage Block Comparator Stylus. Gage on TI near one of the positions identified in Figure 3 and note measurement. Using the crank assembly, move the TI to the opposite position and note measurement. Without making any adjustments to the Gage Block Comparator (2.3), use the crank assembly and back the TI out from under the Gage Block Comparator Stylus and carefully rotate the TI 90. Using the crank assembly, move TI under the Gage Block Comparator Stylus and note the measurements at the last two positions for a total of 4 measurements. The difference between the smallest and the largest observed measurements from the measured positions must not eceed the specifications listed in Table 1. Replace TIs that eceed the Table 1 specifications for the tolerance of the TI set. For all TIs 5 inches to and including 20 inches: When measuring Parallelism using Gage Block Comparator (2.3) that is equipped with movable anvil/crank assembly. It is acceptable to disengage contact between the TI and Gage Block Comparator stylus using the Gage/Retract Lifting Lever prior to moving TI with the anvil/crank assembly. 10

13 Parallelism; Measured Positions for Long Gage Blocks ( 5 to and including 20 inches) 4.3 LENGTH CALIBRATION: (Using Software) Figure Clean the TIs and Master Gage Blocks using Alcohol-Ethyl. Set up the TIs and Master Gage Blocks on a Soak Plate that is located near the Gage Block Comparator TIs and Master Gage Blocks must stabilize prior to performing length measurements as follows: Gage Blocks up to and including 4 inches: Stabilization Time 3 Hours Gage Blocks larger than 4 inches to and including 12 inches: Stabilization Time 4 Hours Gage Blocks larger than 12 inches to and including 20 inches: Stabilization Time 5 Hours From the Main Menu select Configuration and verify that the following Menu boes are set per Table 2. Table 2. Menu Bo Parameter Value Units Nominals Deviations: Temperature: Set to Inches or Millimeters Set to lowest resolution Set to Fahrenheit Environment Epansion Coefficients Room Temp (ºF): 68 Gage Block Temp (ºF): 68 Use Manual Entry: Selected Ceramic (ppm/ F): 5.22 Steel (ppm/ F): 6.39 Tungsten (ppm/ F): 2.56 Chromium Carbide (ppm/ F):

14 Table 2. (Cont.) Menu Bo Parameter Value Penetration Coefficients Gage Select Proper System Steel (µin): 9.76 Ceramic (µin): 9.76 Tungsten (µin): 5.78 Chrome (µin): 7.76 Use Manually Entered Penetration Values Selected Measuring Mode Master Set: Select Master Gage Block Set * Work Block Variation, (µin): 2.0 Allowed Spread, (µin): ** Allowed Column Edits: Check Dev 1, Check Dev 2 * If Master Gage Block Set is not loaded or data is not up to date, consult equipment manual for detailed instructions for loading/updating Master Gage block File. ** Refer to steps or ; enter the Allowed Spread based on the TI requirements From the Main Menu select the Open Set button and access the Test Gage Block Set File. Follow on screen prompts. If Test Gage Block Set File is not loaded or data is not up to date, consult equipment manual for detailed instructions for loading/updating Test Gage Block Set File Select Start to begin Run #1 Measurement Process While observing the Sensor Position Readout, gage on the TI After the Measurement Readout steadies, select Measure Without making any adjustments to the Gage Block Comparator, replace the TI with the Master Gage Block After the Measurement Readout steadies, select Measure Without making any adjustments to the Gage Block Comparator, replace the Master Gage Block with the TI After the Measurement Readout steadies, select Measure If the Test Gage Block Verification fails, select Remeasure to re-start the Measurement Process. Otherwise select Accept Repeat steps through for the remaining TIs for Run #1 Measurement Process Select Stop upon completion of Run #1 Measurement Process Repeat steps through for Run # Review the Dev 1 and Dev 2 measurement results. For TIs where the Spread (µin) eceeds the following specifications, re-measure the TI a third time repeating steps through Otherwise, proceed to step For TIs up to and including 4 inches in length with a length accuracy of 12 µin; the Spread must not eceed 3 μin For TIs up to and including 4 inches in length with a length accuracy of 20 µin; the Spread must not eceed 4 μin. 12

15 For TIs larger than 4 inches to and including 20 inches length with a length accuracy of 2 µin/in; the Spread must not eceed 3 μin For TIs larger than 4 inches to and including 20 inches length with a length accuracy of 3 µin/in; the Spread must not eceed 4 μin For TIs larger than 4 inches to and including 20 inches length with a length accuracy of 5 µin/in; the Spread must not eceed 5 μin Select Report and review all TI deviations from nominal length. Replace and re-calibrate all TIs that have reported deviations from nominal length that eceeds 50 µin, repeating steps through Select Report and print a copy of the measurement report that identifies all TI s and deviations Refer to step 3.3 for information concerning the Report of Measurement and appropriate Certification Label Refer to Appendi C for TI packing instructions If the calibration is complete, secure all equipment, Master Gage Blocks and TIs. 4.4 LENGTH CALIBRATION: (Manual Entry/Calculation) This Gage Block Calibration Process can be used with any AFMETCAL approved Gage Block Comparator configuration. Measurement data obtained from the Gage Block Comparator is recorded and manually calculated to determine the TI deviation from nominal length Clean the TIs and Master Gage Blocks using Alcohol-Ethyl and wipe dry. Set up the TIs and Master Gage Blocks on a Soak Plate that is located near the Gage Block Comparator TIs and Master Gage Blocks must stabilize prior to performing length measurements as follows: Gage Blocks up to and including 4 inches: Gage Blocks larger than 4 inches to and including 12 inches: Stabilization Time 3 Hours Stabilization Time 4 Hours Gage Blocks larger than 12 inches to and including 20 inches: Stabilization Time 5 Hours Make a copy of the Appendi B Worksheet Record the necessary information such as TI Nominal Lengths and Serial Numbers on the Worksheet. Refer to the AFPSL Report of Measurement and record on the Worksheet, all Master Gage Block deviations in columns MD-1 for Run #1 and MD-2 for Run # While observing the Comparator Display, Gage on the TI. For all TIs 5 inches to and including 20 inches: When performing Length Calibration using long Gage Block Comparator (2.3) that is equipped with a movable anvil/crank assembly. Set the TI and Master Gage Block on the Gage Block Comparator (2.3) movable anvil so the gage points are directly across from each other. Using the crank assembly, move TI and Master Gage Block as necessary to obtain measurements. 13

16 For all TIs 5 inches to and including 20 inches: When measuring Parallelism using Gage Block Comparator (2.3) that is equipped with movable anvil/crank assembly. It is acceptable to disengage contact between the TI and Gage Block Comparator stylus using the Gage/Retract Lifting Lever prior to moving TI with the anvil/crank assembly Record the displayed TI value from the Comparator Display on the Worksheet Column labeled T-1. Ensure to record proper sign (+ or -) Without making any adjustments to the Gage Block Comparator, replace the TI with the Master Gage Block Record the displayed Master Gage Block value from the Comparator Display on the Worksheet Column labeled M-1. Ensure to record proper sign (+ or -) Repeat steps through for the remaining TIs for Run #1 Measurement Process Repeat steps through for Run #2 ecept record displayed TI measurements on the Worksheet Column labeled T-2 and the Master Gage Block measurements on the Worksheet Column labeled M Calculate and record on the Worksheet, the TI deviation from nominal length in column T-1 Final (for Run #1) and T-2 Final (for Run #2) using the equations below. Ensure to use and record proper sign (+ or -). T-1 Final = (T-1) - (M-1) + (MD-1) T-2 Final = (T-2) - (M-2) + (MD-2) Review the calculated values for T- 1 Final and T- 2 Final. For TIs where the absolute difference between T-1 Final and T-2 final eceeds the following specifications, re-measure the TI a third time repeating steps through Otherwise, proceed to step For TIs up to and including 4 inches in length with a length accuracy of 12 µin; the absolute difference must not eceed 3 μin For TIs up to and including 4 inches in length with a length accuracy of 20 µin; the absolute difference must not eceed 4 μin For TIs larger than 4 inches to and including 20 inches length with a length accuracy of 2 µin/in; the absolute difference must not eceed 3 μin For TIs larger than 4 inches to and including 20 inches length with a length accuracy of 3 µin/in the absolute difference must not eceed 4 μin For TIs larger than 4 inches to and including 20 inches length with a length accuracy of 5 µin/in; the absolute difference must not eceed 5 μin Calculate and record on the Worksheet, the TI Average Deviation in column T-1 Final (for Run #1) and T-2 Final (for Run #2). Ensure to use and record proper sign (+ or -) Review the Average Deviations from step Replace and re-calibrate, following paragraph 4.4, all TIs whose Average Deviation eceed 50 µin Refer to step 3.3 for information concerning the Report of Measurement and appropriate Certification Label Refer to Appendi C for TI packing instructions If the calibration is complete, secure all equipment, Master Gage Blocks, and TIs. 14

17 4.5 LENGTH CALIBRATION: (Using the Labmaster Universal)) Install the Labmaster Universal radius anvils to accomplish length measurement Clean the TIs using Alcohol-Ethyl and wipe dry Select and clean individual Gage Blocks that will be used to set the Scale Factor. The nominal difference between the two Gage Blocks used to set the Scale Factor shall not be smaller than 3 inches Select and clean an individual Gage Block that will be used to set the Datum: TIs up to and including 8 inches, the Datum Gage Block shall be within 1 inch of the TI nominal length TIs larger than 8 inches up to and including 13 inches, the Datum Gage Block shall be within 2 inches of the TI nominal length Place the Scale Factor Gage Blocks, the Datum Gage Block and TI on the Labmaster Universal staging table to stabilize: Gage Blocks up to and including 4 inches: Stabilize Time = 3 hours Gage Blocks larger than 4 inches up to and including 13 inches: Stabilize Time = 4 hours Gage on the Scale Factor Gage Blocks; align/square each Gage Block. Enter the certified length of both Gage Blocks used to set Scale Factor applying certified Gage Block deviations Place the Scale Factor Gage Blocks back on the Labmaster Universal staging table Gage on the Datum Gage Block; align/square the Gage Block. Enter the certified length of the Gage Block used to set the Datum applying certified Gage Block deviations Place the Datum Gage Block back on the Labmaster Universal staging table Gage on the TI; align/square the TI. Record TI length as L Repeat steps through ecept record TI length as L Calculate and record as T-Diff, the absolute difference between L1 and L If the absolute difference between L1 and L2 eceeds the following, measure the TI a third time repeating steps through Otherwise, proceed to step For TIs up to and including 4 inches in length with a length accuracy of 12 µin; the absolute difference must not eceed 3 µin For TIs up to and including 4 inches in length with a length accuracy of 20 µin; the absolute difference must not eceed 4 µin For TIs larger than 4 inches up to and including 20 inches in length with a length accuracy of 2 µin/in; the absolute difference must not eceed 3 µin For TIs larger than 4 inches up to and including 20 inches in length with a length accuracy of 3 µin/in; the absolute difference must not eceed 4 µin For TIs larger than 4 inches up to and including 20 inches in length with a length accuracy of 5 µin/in; the absolute difference must not eceed 5 µin. 15

18 Calculate and record as L-Final, the average of L1 and L Using the value for L-Final, calculate and record the TI deviation from nominal size Replace and re-calibrate, following para 4.5, all TIs whose Deviation from nominal size eceeds 50 µin Refer to step 3.3 for information concerning the Report of Measurement and appropriate Certification Label Refer to Appendi C for TI packing instructions If calibration is complete, secure all equipment, Master Gage Blocks and TIs. 4.6 GAGE BLOCK ACCESSORIES CALIBRATION: TRIANGULAR BASE WITH OFFSET STEP HALF ROUND JAW RECTANGULAR HALF ROUND JAW SQUARE SURFACES NOT CALIBRATED TRIANGULAR BASE SURFACES CALIBRATED FOR FLATNESS ONLY. STRAIGHT JAW SQUARE STRAIGHT JAW RECTANGULAR = Location where zero(0) or reference is set for parallelism measurement. = Location where parallelism measurements observed. Note: Accessories are not graded. Figure 4. The eamples in Figure 4 represent common styles and types of Gage Block Accessories. Some Accessories have beveled surfaces and may be shaped slightly different. The Calibration Process for the Half Round Jaws and Straight Jaws is based on how they are used when wrung to Gage Blocks to obtain an internal length reference Scriber Point and Center Point will not be calibrated. Identify on the Report of Measurement as not certified Half Round Jaws: Use the Inspection Interferometer to inspect the lapped face for raised burrs, scratches and other surface defects. Only one face is inspected on the Half Round Jaws. Refer to Figure 2. Repair or replace as necessary. Otherwise, identify on the Report of Measurement as not certified Use the Inspection Interferometer to measure the Flatness of the lapped face. Refer to Figure 4. For additional instructions concerning the method of measuring Flatness refer to Figure 2. If the TI does not meet the Flatness specification in Table 1, repair or replace. Otherwise, identify on the Report of Measurement as not certified. 16

19 4.6.3 Straight Jaws: Use the Inspection Interferometer to inspect all lapped faces for raised burrs, scratches and other surface defects. Refer to Figure 4. Repair or replace as necessary. Otherwise, identify on the Report of Measurement as not certified Use the Inspection Interferometer to measure the Flatness of all lapped faces. Refer to Figure 4. For additional instructions concerning the method of measuring Flatness, refer to Figure 2. If the TI does not meet the Flatness specification in Table 1, repair or replace. Otherwise, identify on the Report of Measurement as not certified For all Straight Jaws used with Square Gage Blocks, use the appropriate Gage Block Comparator to measure the Parallelism between the two lapped faces. Place the TI on the appropriate Gage Block Comparator and gage onto the TI lapped face near the center. Zero the appropriate Gage Block Comparator or note the indication. Slide the TI to at least si locations with two of the locations located along the center of the etension and the other four near the corners of square portion. Note the variation from the observed indications (TIR). If the TI does not meet the Parallelism specification in Table 1, repair or replace. Otherwise, identify on the Report of Measurement as not certified For all Straight Jaws used with Rectangular Gage Blocks, use the appropriate Gage Block Comparator to measure the Parallelism between the two lapped faces. Place the TI on the appropriate Gage Block Comparator and gage onto the TI lapped face near the center. Zero the appropriate Gage Block Comparator or note the indication. Slide the TI to at least four locations near the four corners. Note the variation from the observed indications (TIR). If the TI does not meet the Parallelism specification in Table 1, repair or replace. Otherwise, identify on the Report of Measurement as not certified Triangular Bases: For all Triangular Bases, use the Inspection Interferometer to inspect all lapped faces for raised burrs, scratches and other surface defects. Refer to Figure 4. Repair or replace as necessary. Otherwise, identify on the Report of Measurement as not certified For all Triangular Bases, use the Inspection Interferometer to measure the Flatness of all lapped faces. Refer to Figure 4. For additional instructions concerning the method of measuring Flatness, refer to Figure 2. If the TI does not meet the Flatness specification in Table 1, repair or replace. Otherwise, identify on the Report of Measurement as not certified For Triangular Bases without offset step, use the appropriate Gage Block Comparator to measure the Parallelism between the two lapped faces. Place the TI on the appropriate Gage Block Comparator and gage onto the TI lapped face near the center (some Triangular Bases may have a thru hole near the center location). Zero the appropriate Gage Block Comparator or note the indication. Slide the TI to three locations near the three corners. Note the variation from the observed indications (TIR). If the TI does not meet the Parallelism specification in Table 1, repair or replace. Otherwise, identify on the Report of Measurement as not certified For Triangular Bases with offset step, place the TI on the Surface Plate with offset step up. Gage onto and near the center of the TI lapped offset step and zero the Electronic Height Gage or note the indication. Slide the TI to four locations near the four corners. Note the variation from the observed indications (TIR). The TI Parallelism on the lapped offset step shall meet the Parallelism specification in Table 1. Gage onto the surface below the offset step if surface is lapped. Zero the Electronic Height Gage or note the indication. Slide the TI to two locations and observe indications (TIR). Gage onto the surface on the other side of the offset step without moving or re-zeroing Electronic Height Gage. Observe indications at three locations. Note the variation from the observed indications (TIR) from measurements obtained on both sides of the offset step (6 total observed indications). If the TI does not meet the Parallelism specification in Table 1, repair or replace. Otherwise, identify on the Report of Measurement as not certified For Gage Block Accessory Kits that are not part of a Gage Block Set, annotate each Accessory serial number and description on the appropriate Certification Label. If all Accessories cannot be identified on the Certification Label, refer to step 3.3 and complete a Report of Measurement and identify those items relating to the Accessories For individual Gage Block Accessories that are not part of a Gage Block Set, annotate the Accessory serial number and description on the appropriate Certification Label. 17

20 4.6.7 For Gage Block Accessory Kits that are part of a Gage Block Set, refer to step 3.3 for information concerning the Report of Measurement and appropriate Certification Label Refer to Appendi C for TI packing instructions If the calibration is complete, secure all equipment and TIs. CALIBRATION PERFORMANCE TABLE Not Required 18

21 APPENDIX A Page 1 Model No. 81 TMDE Report of Measurement for Gage Blocks For Aircraft Repair Serial No. ELV15 The reported deviations from nominal have a measurement accuracy of: 12 in from stated deviation. Laboratory environmental conditions at the time of calibration: Temperature: 68.5 F Humidity: 37 percent Deviations from nominal length are reported in microinches ( in). A minus sign (-) indicates that the Gage Block is shorter than the nominal length. No sign indicates a plus (+) value and that the Gage Block is longer that the nominal length. Calibrated By: Date: John Doe 01 May 1996 Page 2 Gage Blocks, Serial No: ELV15 Model No: 81 Date: DD/MM/YY Gage Block Material: Chromium Carbide Metric Equivalents Nominal Deviation Deviation Missing Size Gage From Nominal From and/or (inches) Block S/N Nominal ( in) Size (mm) Nominal ( m) not cert UKM UKM CRW CRW ELV ELV16 The reported deviation from nominal for the following Accessory has a measurement accuracy of 12 in TIR: Triangular Base S/N: The reported deviations from nominal for the following Accessories have a measurement accuracy of 12 in TIR: Half Round Jaw S/N: Straight Jaw S/N: Accessories not certified: Center Point Scriber Point S/N: S/N: A-1/(A-2 Blank)

22 APPENDIX B Ensure to record proper sign (+ or -). Worksheet Average Nominal T-1 T-2 Absolute Deviation Length S/N T-1 M-1 MD-1 Final T-2 M-2 MD-2 Final Difference (From Nominal) T-1 = TI indication for Run #1 T-2 = TI indication for Run #2 M-1 = Master Gage Block indication for Run #1 M-2 = Master Gage Block indication for Run #2 MD-1 = Master Gage Block deviation from Report of Measurement for Run #1 MD-2 = Master Gage Block deviation from Report of Measurement for Run #2 T-1 Final = TI deviation from nominal, calculated from data for Run #1 T-2 Final = TI deviation from nominal, calculated from data for Run #2 Absolute = A reproducibility check to compare Run #1 and Run #2 Difference Absolute Difference = T-1 Final T-2 Final Average = Reported and Certified TI deviation from nominal length. Deviation Average Deviation (From Nominal) = (T-1 Final + T-2 Final) 2 (From Nominal) B-1/(B-2 Blank)

23 APPENDIX C GAGE BLOCK PACKING: C-1.1 After the TIs are calibrated, clean with Alcohol-Ethyl and wipe dry. C-1.2 To prevent corrosion, coat the TIs in a light oil preservative if they are to be sent locally, otherwise use a thick oil preservative. C-1.3 Use bubble pack and wa protective paper to ensure that TIs are secure in the protective case. C-1.4 If the TIs are packed properly, the technician should be able to gently shake the protective case without hearing any movement. C-1/(C-2 Blank)