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The BEST way to drill into fiberglass (gelcoat) to prevent chips and tearouts of the gelcoat ... use a portable drill press (or first drill a very small pilot hole if you dont have a press), set up the alignment of the bore, put down a section of masking tape onto the gelcoat, and before your drill put down a sheet of fine (100 grit) sandpaper (face side down) on top of that, and SLOWLY increase pressure of the drill tip as you begin to penetrate through the inverted sand paper and masking tape. Will be 'perfect' hole and without 'tearouts' and flakes .... because the drilling begins as a 'grinding' due to the sandpaper grit ... the masking tape 'strengthens' the gel. Slowly PEEL the masking tape away (alsmost folding the tape over onto itself) when done, dont 'rip it off' nor pull 'up'.
Last edited by RichH; 03-01-2011 at 11:33 AM.