5. To Cut or Not to Cut?
When it comes to the pull-off adhesion test method, one of the questions most often asked is whether the coating should be cut around the dolly prior to testing, or whether it should remain uncut.
This depends on your customer, and the simple answer is to refer back to the test method or standard that you are working to. If the standard doesn’t say, then the choice is for the client and the contractor to determine – but note in your report whether you have cut or not, and be sure all adhesion tests are carried out in the same way.
If you are required to cut around the dolly then, once the adhesive has fully cured, using a knife or dolly cutter, which are typically supplied with the gauge, carefully and safely cut the coating all the way down to the substrate.
Please note that the dolly should not be used as a stabilising peg for the cutter or knife, as any undue shear stress can increase the chance of a glue failure during the pull test, or could cause the coating to fail prematurely.
This video is part of a series on Pull-Off Adhesion Testing, to see the next video please click here.