This paper examines current mechanical surface preparation methods with power tools and standards to help define requirements for applicators. Current use of Replica tape methods on power tool cleaned surfaces to measure the surface profile is intended for abrasive blasted surfaces, and not deemed suitable, costly and time consuming.
The authors have used test panels with various power tool methods to ascertain adhesion properties, and to select appropriate visual standards/comparators that can be applied readily during mechanical surface preparation. It was found that the Bristle blaster disc produced the best pull off adhesive results and was more suitable for weld preparation due it’s flexibility in contact with the weld profile.
The use of Testex tape was replaced with a comparator and visual reference standards approach, the visual reference standard and comparator was sufficient and more efficient in determining appropriate surface preparation as compared to Testex tape.
Conclusions from the tests have enabled the requirements for mechanical surface preparation to be better defined for the applicator and in the Coating Specification.