Powder Coating Quality Control Crosshatch Adhesion Test
The Crosshatch Adhesion testing
This adhesion cross hatch test is widely used when needing to test if a powder coat has been cured and adhered properly to the surface of the coating substrate.
The cross hatch test method is simple and checks the adhesion of powder or adhesion coating to ensure coating quality control.
Why use a Powder Coating Adhesion test
Once a powder-coated item has cooled we carry out an adhesion test to make sure the paint has cured properly and will not lift off the sub layers whether that be HZS & primer, galvanise or an etched sub straight.
Powder coating adhesion test problems
If the test is carried out and flakes of paint are stuck to the tape, this means that the powder coat has not been cured correctly to the coating substrate and the result is a fail of the test. the item will need to be stripped and recoated.
Cross Hatch adhesion test method
We select an area normally not seen, like the base or an underside.
To do this test we need a Elcometer, it’s a crosshatch adhesion testing tool, sticky tape, and our paperwork.
Our paperwork records the date, job number, customer details, who carried out the test and that a photo was taken.
With the blades facing down we push with a lot of force in a vertical and then a horizontal direction, forming a crosshatch, at least twice in each direction. This has gone through the powder coat and broken the surface of the paint. We then place some sticky tape and apply this across the area that has been scored, you need to press it down firmly to ensure the sticky tape is in full contact with the surface of the Item. The tape is then pulled off and checked to see if any of the powder coat has been lifted from the item and that it’s not flaking off.
A pass is no fragments on the tape, and we know that the powder coat has cured properly.
Powder coat cross hatch adhesion test tape
Any high adhesive sticky tape will do the trick. When applying it make sure you press down hard so that the tape and its glue is in full contact with the paints
Powder coating Elcometer cross hatch cutter tool
This is a handheld device that has a roller on one end and a metal blade with teeth fixed to the other end. When you apply downward pressure on the Elcometer cross hatch cutter tool, the metal teeth will score the powder coated paint surface. You use the tool in a horizontal movement and a vertical movement causing the tool to score the power coat in a crosshatch design. This hatching leaves little cut squares of paint and if the paint has been cured properly, then those little hatched squares of paint will not lift then the sticky tape is applied
Powder coating quality control adhesion test problems
If the test is carried out and paint is left on the tape, this is a fail, and the item will need to be stripped and recoated
Powder coating quality control adhesion test kit
To perform this test, you will need: –
The powder coated item
The cross hatch adhesion tool (for this test we used a brand called Elcometer)
High tacky sticky tape
And any paperwork to record the results
You might want a camera to evidence this test with a client