Fiberglass can be one of the most attractive things about
your boat. It can also be one of the most complicated parts of the boat that
you have to deal with. If you ever find yourself in a situation where you need
to trim or cut fiberglass to handle repairs or give it a cosmetic update, it
can feel tricky. That’s why we’ve put together a brief guide on how to cut
fiberglass safely and easily.
Why Cut Boat
Usually, cutting into a boat’s fiberglass is the result of
installing something new—for example, a new radio. If you want to add that to
your boat and minimize the amount of space you use, you’ll often have to cut
into the fiberglass. When you purchase a product designed to be installed
directly into fiberglass, you’ll find it often comes with many of the pieces
and instructions you need to get going.
Make sure you’re working on a relatively clean, smooth
surface. You don’t want to cut into the fiberglass and cut your hand on anything
Using the suggested measurements of the product you’re
installing, it’s time for you to mark out the area you’re going to cut through.
Remember the phrase “measure twice, cut once”? It’s just as true for fiberglass
as it is with wood. Make sure that your measurements are precise, and measure
once more to double-check. It seems like an extra step, but it’s really the
best way to ensure a professional-quality installation.
The first step in puncturing your fiberglass isn’t to
cut—it’s to drill. Using a drill, go carefully in the corner you’ve outlined
for yourself with a marking pen after your measurements. If you haven’t
completed that step already, now’s the time. With these drill-holes in place,
you’ll have a much better idea of what the hole through your fiberglass will
ultimately look like.
Don your safety goggles. Using a jigsaw fitted with a
metal-cutting blade—and not a blade designed for wood use—it’s time to cut
between the holes. Keep in mind that if you have particularly thin fiberglass,
it could flex to a wide degree, so be careful here. You only get to cut the
first time once, so precision and extra caution are warranted.
Once you have the first line through the fiberglass, repeat the
process between the other holes. Remember to venture on the side of cutting inside the holes, as you can always
expand the hole to suit your specific measurements.
Now, clear out any debris. You can use a file to smooth out
the edges. You should now have a hole of the appropriate size in your
fiberglass. Complete the instructions of the item you wanted to install and—voila—you’ve made an addition to your
Maintain Your Boat’s
Dealing with fiberglass is intimidating for a lot of
first-time boat owners, but if you understand how it’s different than wood,
you’ll stand a much greater chance of success. And don’t forget to adequately
prepare your fiberglass in advance with the appropriate boat cleaners from