Surfing School - Glassing - Glossing
Glossing is very difficult and many precautions must be taken if your finish is to look shiny and smooth. Gloss in a room with no dust, and during the daytime when the humidity is low and no bugs are flying around. However, the clean environment is only part of the solution, a very clean brush is the real key to smooth finishes. After a brush has been used once, excess unremoved resin hardens at the base of the bristles, regardless of how well the brush is cleaned. These small pieces will eventually work their way loose and get into the gloss on subsequent boards. Brush hairs also start to come loose after a few cleanings in acetone, and these must be removed when they get into the gloss. Needless to say, glossing brushes only last so long and must be replaced when they start to deteriorate.
The best glossing brush is a 4" or 5" wide natural hair brush with an unfinished wood handle. Acetone will melt the finish on a handle and will also destroy some synthetic hair bristles. To clean the brush, first squeeze all the loose resin out of the bristles with your hand. Work acetone well up into the brush base, and then rinse in progressively cleaner acetone until no resin is detectable. After cleaning, shake the brush vigorously until dry. The brush should be hung upside down in a clean area.
Glossing or finish resin is available off the shelf from many surfboard shops and distributors, and does not need to be blended with styrene or hardener. Only people with experience in glossing should use these agents as they can ruin your finish if used improperly. About 30 cc of styrene is mixed with 2 drops of DNA and just over 2 pints of resin for a professional finish. If using finish resin, add about 40 cc of catalyst to just over 2 pints of resin and mix using a wood stirrer. A good procedure to follow before glossing is to first clean your brush well and then strain about 2 pints of resin into a clean non-waxed paper container. Ordinary paint strainers work well.
Before you pour or mix the resin, tape around the board at the maximum extension of the rail line, deck up first, using 1" high temperature masking tape with the bottom flared out as shown in Figure 01. Make sure the bottom edge of the tape has not accidentally been pushed to the board as this will allow resin to flow onto the bottom surface rather than off the board.
You are now ready to mix and apply the gloss coat. Hold the brush the same as you hold the squeegee, gripping the base rather than the handle. Mix the resin and catalyst together and pour 1/2 the contents down the middle of the board from nose to tail. Pressing lightly down on the brush, work the resin out to the edge of the board closest to you using slightly slanted middle to outside strokes.
Next, go around the board and again pour your remaining resin down the middle from nose to tail. Again work the resin out to the edge of the board closest to you. The board should now be completely covered with a fairly uniform coat of resin.
Covering from nose to tail, make diagonal strokes with the brush across the entire width of the board in the opposite direction from your first strokes, slowly working any thick resin buildups towards the outer edge. Repeat the procedure one last time with strokes again in the opposite direction from the previous brushing. This process will cause the resin to have a very even thickness throughout.
For the final brushing, hold the brush so that the bristle ends slightly touch the board surface. Make long, horizontal strokes starting at the middle of the board and working out to each rail. The final stroke alone each rail should have slight pressure applied to remove any thick resin buildups that have accumulated along the tape. If the resin was applied smoothly, no heavy spots should be visible on the deck or rails.
I like to pull the tape just after the resin starts to set. This helps keep edges smoother for the final rail sanding and buffing. This is also a good time to carefully check the finish over to ensure no specs of dust, loose hairs, or other problems have shown up in the finish. If the resin was set off to hot or there was dust or finger marks on the board, the resin will separate, and the board must be re-sanded and glossed again.
After the board has set for several hours or until the next day, the process is repeated on the bottom of the board. Tape the edge just on top of the previous tape line and also over the fin box (the box only) if there is one. If a hard fin is mounted, make sure you brush all resin buildup from the fin that can accumulate at its base. This may require only placing a very light coat of resin on the fin and then strongly brushing off any resin drops as soon as they appear.