Building a Hatch Opening

The water-tight bulkhead forward of the engine compartment needs a hatch opening so you can access the area forward of frame 3.  We have to cut an opening and frame it and the hatch.  We’ll have to design the frame for both pieces, determine proper placement of the hinges and opening hardware, and make it waterproof.

The first step is to design the frame.  It needs to be water tight, so I’ll use silicon weather stripping to provide the seal.  Since the bulkhead is there to keep the boat from flooding in the event of a crash, the hatch should open forward.  If the front compartment floods, the water pressure will force the hatch closed instead of open.  A good frame not only looks good, it adds strength.  It’s also a good idea to determine all the hardware you’ll need and make sure it works with your design.

Now cut the opening in the plywood bulkhead.  Drill the corners to keep from having a sharp corner, and then use a router with a guide to cut out the opening.  Don’t forget to allow for the width of the frame when determining where to cut the hole!

Mill out your framing stock and cut the frame to fit.  It’s a little tedious to get the miter for the corners exactly right, but it’s worth it when you see a corner that fits perfectly.  After checking and re-checking, glue it up.

The hardware will be mounted using wood screws.  The best way to do this and keep the screw penetrations from allowing a path for water to get in and start rotting the wood is to over drill all the screw holes and fill them with epoxy.  Take a close look at the bump-out in the frame at left.  You might have to enlarge the picture to see those epoxy filled screw holes.  Of course, we’ll also use sealant when putting the screws in as well.

Everything gets at least 3 coats of epoxy, sanding between coats.  This not only looks great, it’s a great way to seal the wood.  Stay tuned!  We’ll finish up in the next post.