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  1. #1
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    Cutting a hole in fiberglass

    I want to cut a access hole 4'' or 5'' diameter on the inside of my red Skeeter for access. I don't want to chip the paint. Should I use a vertical moving jigsaw or a hole saw and should I tape it. Advice is appreciated. I've drilled into it and installed brackets but never cut a hole.

  2. Member
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    #2
    You could put tape on the fiberglass first. Then take a holesaw and get your pilot hole through. Then run the holesaw in reverse until it’s through the gelcoat. That should prevent it from chipping

  3. Member
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    #3
    Quote Originally Posted by basscat tyler View Post
    You could put tape on the fiberglass first. Then take a holesaw and get your pilot hole through. Then run the holesaw in reverse until it’s through the gelcoat. That should prevent it from chipping

  4. Member
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    #4
    Quote Originally Posted by basscat tyler View Post
    You could put tape on the fiberglass first. Then take a holesaw and get your pilot hole through. Then run the holesaw in reverse until it’s through the gelcoat. That should prevent it from chipping
    This, also don't get in a hurry. I have put many a hole in lots of boats installing stuff. Never a problem. I also finish the newly cut hole with a half round file around the edges for safe measure.

  5. Member
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    #5
    Use a new holesaw. Run it in reverse. It will go through very easily and smoothly

  6. Member
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    #6
    Quote Originally Posted by basscat tyler View Post
    You could put tape on the fiberglass first. Then take a holesaw and get your pilot hole through. Then run the holesaw in reverse until it’s through the gelcoat. That should prevent it from chipping
    this is the only way with a fresh blade also
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  7. Member
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    #7
    Just like most everyone said.
    1/4 inch drill bit to start, get your correct size holesaw, run in reverse first very slow to start to cut the gelcoat top layer, then run forward again very slow. I never used tape, but it couldn't hurt.

  8. Member
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    #8
    If you need a rectangular hole that going to be cut in from the "show" side, get a reverse-tooth jigsaw blade (made for cutting plastic laminates). Cover the base of the saw with painters tape. Tape out the cut, drill the corners and turn off the orbital action on the saw prior. Watch out for the fibers on the backside!

  9. Member FES313's Avatar
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    #9
    Ceramic cutoff wheels and diamond hole saws make very clean cuts and do not chip out gel coat. They are a little more expensive but its worth it for the results. Hole saws still needs to be run in reverse. examples below.

    https://www.mscdirect.com/product/details/81680324

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  10. Banned
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    #10
    Go into any good rigging shop and they are running hole saws backwards.

  11. Member
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    #11
    Quote Originally Posted by basscat tyler View Post
    You could put tape on the fiberglass first. Then take a holesaw and get your pilot hole through. Then run the holesaw in reverse until it’s through the gelcoat. That should prevent it from chipping
    I was terrified to drill into my then brand new Cat, but really wanted to add the Noco charge receptacle. I would rate myself a 2/10 on the handiness scale, and was able to pull this off flawlessly following this technique.
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  12. RIP Evinrude 1907-2020 JR19's Avatar
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    #12
    Quote Originally Posted by BKF View Post
    Use a new holesaw. Run it in reverse. It will go through very easily and smoothly
    ^this...go slow with light pressure until you get through the gel coat. Once you hit fiberglass put it in forward and go slow with light pressure.

  13. Member
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    #13
    Quote Originally Posted by PMantle View Post
    I was terrified to drill into my then brand new Cat, but really wanted to add the Noco charge receptacle. I would rate myself a 2/10 on the handiness scale, and was able to pull this off flawlessly following this technique.
    Just wait til you have to cut out for a recessed trolling motor and you really cant see what's underneath.
    That takes courage. lol

  14. Member
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    #14
    Use a hole saw and if the area you drill thru has a wood core make sure to seal up that wood after you drill it with either an epoxy for best results or even silicone around the edges. In my (little) bits of experience it seems that the number one cause of rotted boat transom, stringers, decks, etc, is people adding after market holes without sealing the edges or improperly sealed factory holes.