"Knot Likely" -- Hatches

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I could never decide if the hatches on the Return changed or if the deck radius changes when the two halves of the boat were joined. In any case, I decided to add stiffners to the hatches this time, before I cut the hatches out. In fact, I added two layers of 6 oz as stiffners UNDER the 3.25 oz glass used to cover the inside of the deck. Next time, I'll add the stiffners after the deck glass goes down. It was too much hassle trying to get the bubbles out from the edges of the stiffner. I do like the stiffners, however! These hatch covers aren't going to change shape!

As usual, cutting out the hatches is nerve racking. Everyone seems to have a different method. In this case, I default to the Tim Allen method and just use "more power." A plunge cut with the sabre saw seems to do the trick!

On this boat, I ended up cutting four holes in the deck (in addition to the cockpit!). I fell in love with the day hatch on the Return and never questioned if I would put one in this boat. I debated about putting in the port for a hydration bladder, but did while I was drilling holes in the deck for other things. The square hole in the bow is to inset a compass. I wanted to move the compass forward on this boat, but the use of magnetic hatches limits the choice of locations. My tests indicated the compass needed to be at least 20" from the nearest hatch magnet. In this case, it's over 24".

I made the recesses for the magnets using a 1/2" forstner bit in the hand drill. Magnet spacing was about 5.5" on average. I covered the magnets with a layer of bias cut .75 oz (yes, 3/4 oz) cloth that then wrapped over the edge of the hatch cover. This is the first step in trying to protect the magnets and keep them from corroding.

The covers were taped in place, making every effort to keep them flush with the deck. When it is all done, I want the cover sitting down onto the hatch lip, with the gasket seat slightly recessed. I used masking tape because I expected (correctly, it turned out) that I would be done with this step within 24 hours so that I could get the tape off.

I used shelf liner as a parting surface on the inside. The blue tape went down first, just to give me a visual indication of the location for the edge of the hatch lip molding. Unlike last time, this shelf liner left LOTS of sticky stuff behind. While it worked very well for a parting surface, it was miserable to clean up the residue on the inside of the deck.

I put down double faced tape where the gasket recess would go. The tape was just about 1/16" thick, and I thought the waxy paper peel layer would make a reasonable parting surface.

I put down a first layer of 3.25 oz glass butted up against the edge of the double faced tape. That was followed by a layer of 5 oz. carbon fiber. The CF wasn't really necessary, but I'd used it on the cockpit coaming and wanted to carry the theme through to the hatch lips.

Once the two layers were down, the magnets went in place. Since the matching magnets were already installed in the hatch cover, it was impossible to put these magnets on in the wrong location or with the wrong orientation. I could have put them on between the glass and the carbon fiber layer, but I decided to "hide" them in the molding.

I faired around the magnets with some epoxy paste, and then cover the magnets and double faced tape with a layer of 6 oz glass, another layer of CF, and then two final layers of 6 oz. glass. Since I wasn't trying to mold a more complex and deeper channel for a gasket, I didn't bother with bags of sand to weight it down.

Once the lip moldings had cured, they were removed and marked for trimming. The hatch covers themselves were used to determine where the outside cut line would go.

The outside was trimmed to the line, while the inside was trimmed even with the inside edge of the tape. I used a very fine tooth "hacksaw style" blade in the sabre saw for all the trimming.

The waxy paper coating on the double faced tape didn't come free quite as easily as I'd hoped, but it was still much easier than cleaning up the groove when I made a set using foam rubber gasket for the form. A little sandpaper and a touch up with epoxy and we'll be in business.

The hatch lips and hatch covers went back in place to check for fit. After carefully checking that the lid was centered in the cutout, I traced around the outside of the hatch rim.

Using the line as a guide, I masked off, leaving room for a fillet of epoxy around the hatch rim.

Using more thickened and tinted epoxy, the hatch rim was glued in place. A smooth fillet was formed around the edge of the hatch rim. Be careful and complete in cleaning up any squeeze out on the other side of the joint. Any squeeze out will keep the hatch lid from seating accurately.