COATINGS COMPATIBILITY & ADHESION
TESTS (ABOVE WATER ONLY)
Test One: Cross Hatch Adhesion (See diagram above)
- Select test area(s) on the surface to be painted. Thoroughly clean,
de-wax and degrease this area.
- With a sharp blade, cut 6 lines vertically and 6 lines horizontally to give
a box of 25 squares. The cuts must be deep enough to reach the
substrate. On thick fairing systems this test may have to be done to
several different layers.
- Apply 3M #610, #895 or #898 3M Scotch Brand Filament Tape (or
similar type of packaging tape) over the scribed area, making certain
that the tape is tightly adhered to the test surface. Do not use
- With an abrupt yank, pull the tape back parallel to the surface. Pulling
the tape straight up will give no test at all.
- Examine the test surface. If any square of old coating in the scribed
area is removed, the adhesion has failed. All the failed layers must
Test Two: Solvent Resistance
- Saturate a cotton ball or small wad of cloth with one of the
Awlgrip Topcoat or Primer Reducers (T0003 or T0006).
- Tape the reducer-saturated ball to the scribed area surface for
- After 30 minutes remove the cotton ball. If the reducer has dissolved
or severely softened the old coating, the coating is incompatible and
must be removed. If the scribed area has remained intact, allow a
15 minute recovery period and repeat all steps in Test One again.
- If any square areas are removed, all the failed layers must be
Test Three: Coating Compatibility
If the old coating is still intact after Tests One and Two, perform
- Lightly sand a small test area with 220 grit paper. Clean the sanded
areas thoroughly with Awlgrip Wipe-Down Solvent (NA/AP:
Awlprep T0008 ; EU: Surface Cleaner T0340) and using clean cloths.
- Paint a small patch of the surface with Awlgrip Topcoat. Do not use
masking tape on the edges of the test application as the paint edges
created by the tape will ‘print through’ and be visible in the finish.