Back in early June I removed the dilapidated old sea hood in order to fix and finish the companionway hatch. Since I’m having so much fun working with fiberglass and resins lately, I figured now would be a great time to build a new hatch turtle. Ugh….
Get on the Google and there are zero companies building commercially available fiberglass sea hoods. I guess either your boat came equipped with one, or it didn’t. I stumbled across several web pages of boat fixer-uppers like myself who’ve built their own custom turtles, but most of those were made out of wood and then glassed over with fiberglass cloth. I wasn’t real keen on the idea of building one with a wood core since it seems like water always manages to find its way inside, causing things to rot. Don Casey’s book This Old Boat has a chapter on building a mold and laying up a sea hood out of glass cloth and polyester resin so I decided to go that route. After last summer’s somewhat expensive cockpit coaming project, I opted for the more economical polyester resin rather than using gallons and gallons of epoxy again.
Once I took some measurements and made a template representing the curve of the cabin top, I went to work building the mold. The design is pretty basic and actually looks like a lower profile version of the original. I wanted it fairly short in heigh so it will fit under the new traveller bar, and long enough to extend aft so the new dodger has something to fasten to. The mold was made from MDF and plywood leftover from another project (and a few scraps from work). Once it was all glued and nailed together I filleted the inside corners with thickened epoxy because fiberglass cloth and mat hate bending around square angles. The mold received two coats of sprayed PVA mold release which is a water soluble green colored spray that polyester resin supposedly doesn’t stick to.
Laying up the glass was once again a team effort and Jeni is just as skilled mixing polyester resin as she is epoxy. We pre-cut all the glass cloth and mat that we thought we needed, clipping scraps for the corners and fitting it the best we could. Having never worked with polyester resin I wasn’t quite sure how it was all going to lay up, or how that glass mat was going to behave around all those tight corners. Four layers of woven cloth, and three layers of random strand mat later (and one more trip to TAP Plastics for another gallon of resin), we managed to fill the mold with what I thought would be a sufficient thickness. There’s no way I could’ve managed to fit all these layers of glass in without her help, and despite my frequent fits of rage she stuck it out and put up with my bullshit till the end. Once it cured, prying it out of the mold was a bit of a trick, and I virtually destroyed it removing the new hood. But, I managed to remove the part while Jeni stood aside taking pictures and laughing at me. Back at the boat, it actually fit pretty well. High five…..
Unfortunately, I wasn’t too happy with the overall strength of the sea hood, despite the nearly 1/4″ thick layup. I wanted it to be strong enough to stand on without worry, but it seemed to deflect quite a bit in the middle. I ripped down strips of teak (salvaged from the old sea hood) and epoxied and screwed them in place to help support the middle. I also added a tapered flange at the aft edge for the future mounting of the dodger hardware (more on the dodger in a later post). After fairing with thickened epoxy, and quite a bit of sanding I laid on two layers of 3″ and 4″ glass tape over the wood strips, and then faired all that in with more thickened epoxy.
After the epoxy cured and everything was sanded smooth, the whole thing got a nice scrubbing with fresh water and soap to remove any residual amine blush. Next, everything received a thorough wipe down with Interlux 202 Solvent Wash and was allowed to dry. I mixed up a batch of Interlux Epoxy Primekote thinned about 20% with 2333N reducing solvent and coated everything inside and out with a foam roller. Currently she’s sitting in the shed curing. Tomorrow I’ll hit it with some 220 grit, some more solvent wipe down to remove the dust, and fill in any holidays with Interlux Watertite which is a 2 part epoxy fairing compound. One more coat of Epoxy Primekote over the fairing compound and it should be ready for paint.