SURFACE PREPARATION 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 masking tape.
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 be removed.
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 30 minutes.
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 removed.
Test Three: Coating Compatibility If the old coating is still intact after Tests One and Two, perform Test Three.
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.
Antifouling bottom paint is needed if you store your boat in the water. If left in the water without protection, marine growth may attach to your boat’s exposed hull. Marine growth slows a boat down and increases fuel consumption. Here are the items that you will need in addition to the bottom paint for the proper anti-fouling bottom paint application.
• 60–100 grit – Suitable for the removal of paint or to sand gel coat prior to the application of antifouling paint.
• After sanding remove sanding residue by wiping with a cloth that has been dampened with the proper solvent.
• Masking Tape– When it is necessary to mask off areas use a high quality clean edge masking tape, especially when the masking tape will be left on the surface for a long time.
• Brushes – For antifouling paints use a natural bristle brush but not necessarily one of as good quality as you would use to apply topside finishes.
• Rollers – Most solvent resistant rollers will have a phenolic core and will say that they are for use with oil based paints or epoxies. For antifouling paint and epoxy primers, use a 3/8”-1/2” nap roller.
Painting a wooden boat on your own can be a daunting task. The amount of information about the correct way to paint a boat is staggering! First time boat owners may be at a loss when trying to make a plan for their first project. The Bottom Paint Store’s aim is to make this process as stress-free as possible so you can enjoy working on your boat and ultimately, enjoy the fruits of your labor!
If your boat stays in the water and growth is a concern you’ll want to use an antifouling paint for below the waterline and follow the manufacturers specs for application to a wood hull. See application instructions of ablative antifouling:
Step 1 – CLEAN SURFACE
Surface must be clean, dry and free of contaminants.
Step 2 – SAND & CLEAN
Sand to a uniformly frosty, dull looking surface with 80-100 grit (no finer)
sandpaper; remove any residue.
Step 3 – APPLY ANTIFOULANT
Apply two coats of Sea Hawk antifouling by brush, roller or spray.
Apply first coat thinned 20% and let dry overnight. Apply two more
coats of bottom paint allowing 3 to 6 hours between coats and a
minimum overnight dry.*
Other Paint Products for Single Day Use
Here are some other products that are not recommended for long-term submersion but can be applied to wood-hulled boats.