Instruments, measuring magnetic induction current

Primers are usually applied to a dry film thickness of 5 to 10 pm. Cover coat adhesives are applied at dry film thicknesses of 10 to 15 pm. One coat adhesives work best at applied dry film thicknesses of 20 to 25 pm. Measuring instrnments to check dry film thickness should be used to insure adequate adhesive application and as a quality control check. Beta backscatter machines work well for all types of inorganic surfaces. However, they are not suitable for adhesives that contain radiation absorbers such as lead. Magnetic induction current instruments work well on steel, but not on non-magnetic substrates such as aluminum or glass. 

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