A precision Nickel Comparator Plate which conforms to International Standard ISO 8503 for grit and shotblast surface roughness comparison measurement
When steel has been blast cleaned, the surface consists of random irregularities with peaks and valleys that are not easily characterized. Experts have recommended that the profile should be identified as dimpled (shot blast) or angular (grit blast) and that they should be graded as Fine, Medium or Coarse with each grade being defined by limits specified in ISO 8503, these characteristics are considered to give sufficient distinguishing features for most painting requirements.
Easy to use, place the Comparator against an area of the test surface, compare in turn the four sectors of the four sectors of the Comparator against the test surface using the X7 magnifier, placed so that the test surface is viewed
Simultaneously with a segment of the Comparator, the nearest profile to the Comparator determines the grade.
The different grades are defined as follows. Fine grade profiles equal to segment 1 and up to but excluding segment 2, Medium grade profiles equal to segment 1 and up to but excluding segment 3 and Coarse grade profiles equal to segment 3 and up to but excluding segment 4.
Supplied in a Protective Wallet.