A25 Hard top project update

[DesertAlbin736]

Don recently posted a thread about his progress on building a hard top for his A27 "Beta Carina".

Here's the latest status on the hard top I'm building for my A25 "La Dolce Vita" I've been working on this thing since late October, starting with building a mold and laying up a foam cored fiberglass panel with openings for two 18 X 18 hatches. Those hatches are strategically located such that when open I can stand at the helm and stick my head out to see better for maneuvering.

Rather than taking the easy way out by buying a pair of Bomar hatches **expensive!! ** I opted to build my own teak hatch covers with 10" X 10" acrylic plexiglass windows in the center. This projects seems to be going on FOREVER, but the end is now in sight.

Fabrication and fitting of the hard top itself is complete except for final painting with Interlux Brightside Polyurethane deck paint (gelcoat did not turn out well).

Just this morning I finally finished the joinery work cutting and fitting pieces for both hatch covers. Side frames made out of 3/4" thick Iroko so-called "African teak" hardwood, corner joints are 'hidden' box joints. The tops consist of a layer of 1/4" birch plywood, glassed & sealed with woven f/g cloth and West System 105 epoxy resin, the under side to also be painted with deck paint, plus a top finish layer of 9MM marine grade teak veneer Okueme plywood for a total thickness of 5/8". I cut shallow kerf grooves in the teak veneer to simulate salty looking teak trim boards. Those grooves will be sealed with black polysulfide caulk, and the whole thing finished with varnish over epoxy resin.

So that's where I'm at now. Remaining work yet to be done includes final fastening and finishing of said hatches, painting the hard top, installing hinges, hatch latches, and prop rods, plus attaching and wiring the solar panel shown in these photos, and of course installing the hard top on the boat. Screw holes for through bolting the hard top onto the wheel house have already been drilled and sealed with epoxy.

[JT48348]

Nicely done. This is a very cool project.

[DesertAlbin736]

Latest and greatest as of Friday night, 2/5/14

Finished installing hinges, latches, and hatch adjuster hardware after painting 2nd coat of Interlux polyurethane deck paint. Right now only thing lacking is final epoxy and varnish finishing of the hatch covers and final install of the solar panel. This is a 20 watt Seimens rigid solar panel. In these pictures it's just sitting on top and hasn't be bolted down yet. Haven't finished installed the plexiglass view windows, and won't until after varnishing is done.

Am a little bummed about the hatch adjusters because I had to bolt them from underneath with acorn nuts on top instead of with the screw heads and trim washers on top because there wasn't enough clearance for the adjuster arms to fold flat without hitting the nuts on the underside.

Double latches and adjuster arms may seem like overkill, but the previous hardtop had problems blowing open on the highway, and that's not going to happen again if I can help it.

[don123]

Very nice!

I envy your woodworking/fiberglass skills - My project is pretty crude by comparison

Don

[DesertAlbin736]

The hardtop project is done* & installed on the boat, FINALLY!!! New pictures coming soon. Ran out of daylight today & didn't take any pics yet. We're headed to the lake tomorrow for first time out with the new hard top. I'm waiting on a special order from West Marine for a can of West System 207 special clear hardener for the 105 resin I already have on hand before varnishing the wood. But it's an easy matter to take the hatch covers off, since the hinges have pins held in place with split ring keepers. Still have temporary rough lumber practice hatches that can be put on while working on the good ones.

The hard top is everything I visualized it being. Good ventilation, tinted 10" X 10" 'moonroof' windows in the hatch covers. Previous owner had the Siemens 20 watt solar panel wired direct to the batteries, no on-off switch, no load controller, no fuses. Duh?!?!?! He also had the cable routed down the outside of the wheelhouse, and in through a hole in the side wall below the starboard window. It would get stretched tight when the old 'poptop' was open. I rerouted a new 14 ga marine grade boat cable down through the the center of the roof, along the inside above the starboard window frame and down to a bulkhead mounted charge controller and a dash mounted on/off toggle switch with inline 5 amp fuse (solar panel is rated at 1.6 amp output and the controller is rated at 7 amp capacity). That way, if I don't want the solar panel on, for example when the engine is running or we're on shore power, I just flick the switch and it's isolated from the electrical system.


*except for finishing the hatch covers with varnish over West System 105 resin

[don123]

Previous owner had the Siemens 20 watt solar panel wired direct to the batteries, no on-off switch, no load controller, no fuses. Duh?!?!?!

While a fuse would probably be a good idea, you don't need a regulator. If you have a pair of 75 to 100 amp 12 volt batteries, having a 20 watt panel directly connected to them is like having a 1.5 amp trickle charger on them 24/7 . . . . except that the panel is probably seldom putting out it's full 1.6 amps and even then, only for 8 or 10 hours per day. It's not really a 'charging system' . . . . the panel's output is only capable keeping up with the self discharge of the batteries . . . . it's never going to 'charge' them, so regulator needed. No reason to disconnect it when running or when on shore power either, IMO

Don

[DesertAlbin736]

Hard top installed at last! Hatch covers are unvarnished in these photos, so there's still that to do, but otherwise complete. We had the boat out last weekend for the first time with the new top. Ventilation was great, and it was like having a T top with moon roof & could look up through the hatch windows and see the stars at night.

[Jay Knoll]

Great job, good to see something finished! Wish I could say the same with my project(s). I've got a serious case of "might as wells" and the punch list gets longer rather than shorter. Oh well, I don't play golf so I've got plenty of time to work on the boat.

[JT48348]

Exceptional job and well thought out. I like this idea alot and the hatches are great

[DesertAlbin736]

Thanks JT. The hatches were a must for our warm climate. The pilot house heats up in the sun like a parked car when closed up, since the side windows are fixed and don't open. I purposely located the hatches where I can stand up at the helm and stick my head out.

Picture below shows what the old one looked like with the top hinged open. Good ventilation, but the spring props limited how much the top could open, and I really couldn't stick my head out & stand up at the helm. And of course you could never get a completely watertight seal when closed no matter how tight you dogged down the latches, and it tended to catch air and blow open when trailering on the highway. The new top is quite a bit heavier, the fiberglass panel weighing in at about 28 lbs, plus the hatches weigh about 8 lbs each and another 5 or so lbs for the solar panel, whereas the old plexi top didn't weigh more than about 15 or 20 lbs max.

[DesertAlbin736]

This project seemed to take on a life of it's own and go on forever. Now five months later it's finally complete, along with stripping all six grab rails down to bare wood and laying on 3 coats of epoxy resin and 4 coats of varnish.

So to close this thread out and recap, here are a couple photos of the finished product.

The hatches consist of frames made of Iroko ripped and milled from 3/4 inch X 6 inch 4/4 boards. The corner joints are modified "hidden box joints". Sort of like hidden dovetails, but the pins are rectangular, not angled. Much easier to cut and fit that way. The sides were glued with JB Weld epoxy, and tops with 4200 adhesive caulk. All very solid. The tops consists of two layers of plywood, an inside layer of 1/4" birch plywoood, sealed with epoxy and the inside surface laminated with fiberglass cloth and epoxy and finished with 3 coats of Interlux white glossy one part urethane deck paint. The outer layer is 9MM marine grade teak veneer Okeume ply, into which I cut 1/8 inch wide by 1/16 deep grooves using a radial arm saw fitted with a kerf blade. Those grooves I filled with black polysulfide caulk to simulate teak planking. In the center I fitted 10" X 10" tinted acrylic plexi windows. Using two layers of plywood was so that I'd be able to mount the windows flush and be able to through bolt them with #8 s/s machine screws with trim washers and lock nuts. The windows are caulked with clear silicone. Then the tops and sides of the hatches were finished with three coats of West System 105 resin catalyzed with #207 special clear hardener mixed at the recommended 3:1 ratio and topped with four coats of spar varnish.

The hatches provide excellent ventilation and seal tight with two latches each and two prop rod adjusters each, as well the skylight windows let in lots of light but are tinted with UV resistant film. Our next project is new cockpit enclosure canvas, and also some Phifertex sun and bug screens using Velcro to attach under the hatch openings when the hatches are open. Also while we're at making new cockpit enclosure we plan to make Sunbrella covers for both hatches and all grab rails since we have no choice but to store our boat out in the open under the relentless Arizona sun, with summer temps as high a 115. That is unless we escape to cooler climes for the summer, which we hope to do this year. We were able to borrow a Sailrite LSZ-1 machine from sailboater friends to do the sewing.

As mentioned in earlier posts, the hard top is a 3/4" layup of isothalic resin, an outer layer of woven fiberglass cloth, then alternating layers of chopped strand mat and 1/8 inch thick Divinycell foam coring, all laid up in a mold of my own design and construction.

In addition, last year I had made name boards out of white oak to go on the sides of the pilot house. Those did not hold up well, so I made new ones of genuine mahogony finished the same way as the hatches and grab rails.