To anyone who’s never done it before, installing a new ventilator, hatch or deck plate can seem a bit intimidating. But with the right guidance and tools, this relatively common modification to your boat becomes easy. Let’s take a look:
Look and Measure Twice
No matter where you decide to install the hatch or deck plate, the first thing is to find out what’s on the other side of the surface, whether it’s wiring, headliner material or a light fixture. This is one area where guesswork is out of the question.
Create a tape outline of where you plan to cut and then follow it with a bladeless saw to check for any possible interference, especially around corners. If there is, use a different saw or carefully cut through the area with a hand saw. You also want to make sure that the area does not have too much crown, as the hatch manufacturer specifies a set maximum amount of curvature the hatch can accommodate.
Making the Cut
First, trace the outline with the hatch itself or the supplied paper pattern, making sure it’s squared with the boat’s centerline. Cut any fabric out of the way on the other side before cutting through with a saber saw or, preferably, a hole saw or a circle cutter. If necessary, you can even use a rotary Dremel tool to cut through the area. Afterward, grab a piece of coarse sandpaper to smooth out the edges.
After you’ve made the cutout, you’ll have to trim away a small amount – approximately a half-inch or more – of the wood or foam core material. Sand the interior surface and then apply unthickened epoxy to the area. After thickening the epoxy to a peanut butter consistency with silica or fibers, fill the gap around the cutout and wait for the epoxy to cure.
Next, you’ll want to use a straightedge to measure the curvature across the deck, just beyond the cutout. For cutouts with a slight curve, you’ll want to use epoxy paste or fiberglass laminate to build up the deck surrounding the cutout. You can also use a flat-top spacer that mimics the deck curvature on the bottom. Avoid grinding down the crown, as it will only weaken the deck further.
Installation and Finishing
Now is the time to dry-fit the hatch and drill the pilot holes for the screws. Use masking tape to define the perimeter of the hatch, and then coat the area between the mask and cutout with sealant. Be sure to use silicone or a silicone/polyurethane blend for plastic hatch and deck plate frames or polysulfide for metal frames. At this point, drop the hatch over the cutout and tighten it evenly. Be careful not to over-tighten the screws – doing so will squeeze the sealant out by accident.
An improperly installed hatch can cause a variety of problems, especially if it’s not properly framed and sealed. You’ll want your hatch or deck plate to be as watertight as possible. A set of o-ring seals can help prevent water from leaking through by providing the tightest possible seal.
The final step involves allowing the sealant to cure for up to three days. Afterward, remove the excess from around the hatch frame with a hobby knife and remove the masking tape.
Keeping your boat in good shape is crucial to safety and the overall fun you’ll have with your boat. Make sure you’re as well-equipped as your boat by learning proper regulations in your area, including if you need a boating license in certain states.