1、GM DAEWOO Auto & Technology. EDS Engineering, GM DAEWOO Auto & Technology. Standards TEST METHOD FOR FILM THICKNESS OF PAINT COATINGS EDS-T-7970 ISSUED DATE: 2000. 06. 30 REVISED DATE: 2005. 09. 06 VERSION: 2 EDS-T-7970 TEST METHOD FOR FILM THICKNESS OF PAINT COATINGS PAGE: 1/3 ISSUED DATE: 2000. 06
2、. 30 REVISED DATE: 2005. 09. 06 VERSION: 2 GM DAEWOO Auto & Technology. 1. PURPOSE This standard aims at specifying the method of measuring the film thickness of the organic coat for automobiles, which is used in the paint shop and assembly shop, in the wet and dry conditions. 2. SCOPE This standard
3、 applies to film thickness measuring of the electro-deposition film, sealer film, primer surfacer/top coat film and wax film. 3. TEST APPARATUS 3.1. Dry film thickness gauge Fig 1. Dry film thickness gauge Fig 2. Compensation plate 3.2. Wet film thickness gauge Fig 3. Wet film thickness gauge ProbeW
4、et film thickness measuring portion (based on height difference between surfaces A & C and B) A BC EDS-T-7970 TEST METHOD FOR FILM THICKNESS OF PAINT COATINGS PAGE: 2/3 ISSUED DATE: 2000. 06. 30 REVISED DATE: 2005. 09. 06 VERSION: 2 GM DAEWOO Auto & Technology. 4. MEASURING WITH DRY FILM THICKNESS G
5、AUGE 4.1. Prior to film thickness measuring, compensate the film thickness gauge according to clause 4.34.5. 4.2. It is the gauge to measure thickness of the electro-deposition film and primer surfacer/top coat film. For film thickness measuring of the sealer, use the dry film thickness gauge, which
6、 has a wider range. Fig 1 4.3. Perform zero setting on the compensation plate Fig 2. Measure until the identical value appears 3 times and perform zero setting. 4.4. After zero setting, have the probe stay in close contact with the standard surface within the film thickness range to be measured and
7、measure until the identical value appears 3 times. Subsequently input the standard film thickness to perform compensation. 4.5. Upon completing compensation, measure the standard film thickness again to check for proper compensation. If compensation has not been conducted successfully, repeat clause
8、s 4.34.5. 4.6. When measuring the film with a different film thickness range, be sure to perform compensation to 4.34.5 and measure the film thickness. 4.7. Have the probe of the compensated film thickness gauge stay in close contact with the portion to be measured and measure the value. 4.8. Evalua
9、tion 4.8.1. When measuring the test piece, measure the film thickness over the entire sides of the test piece and record the mean. 4.8.2. Around holes, curved portions or within 8X from the edge are excluded from measuring. 5. MEASURING WITH WET FILM THICKNESS GAUGE 5.1. It is to measure the thickne
10、ss of the wet-applied wax. Measuring shall be conducted within 2 hours from wax application. EDS-T-7970 TEST METHOD FOR FILM THICKNESS OF PAINT COATINGS PAGE: 3/3 ISSUED DATE: 2000. 06. 30 REVISED DATE: 2005. 09. 06 VERSION: 2 GM DAEWOO Auto & Technology. 5.2. When measuring with the wet film thickn
11、ess gauge after wax application, be sure to perform measuring on a level surface. 5.3. After selecting the film thickness range of the gage according to the film thickness of the portion to be measured, have the “0” portion of the side remain in contact with the surface, grip the handle around the c
12、enter and slowly rotate the wet film thickness gauge at a constant rate. 5.4. After turning the measuring gauge a round, read the first portion of the side “B” where the wax is stuck. 5.5. If the wax is stuck throughout the side “B” or not at all, repeat 5.35.4 with a gauge having a different film thickness range. 5.6. Evaluation 5.6.1. Get the mean of 3 measurements.