Tuesday, December 02, 2008

Double-Coaming Bow Hatches

As you may have guessed from the length of time since my last post, work on the Tiki 26 has slowed due to other obligations and considerations. I'm expecting to pick up the pace again shortly, despite the arrival of colder weather which interferes with the curing of the epoxy.

One project that I have been working on is building the double-coaming hatches that provide access to the forward storage compartments in the bows. These compartments are sealed off from the main cabin areas by watertight bulkheads that go from the keel to the deck, so having totally waterproof hatches here is not absolutely necessary. It will be nice, however, to not have to worry about these compartments filling in rough situations where solid water might sweep the decks, so I have elected to go to the extra trouble of building double coaming hatches, rather than the simple lid hatches shown in the plans.

This type of hatch is the most waterproof design you can build with wood and epoxy, and does not require a gasket-type of seal to keep the water out. The design consists of a high inner coaming and then an extra outer coaming about half as high that meets the overhanging hatch trim. The outer coaming turns away most of the water, but if any gets in, it is stopped by the inner coaming and then drains back out via a couple of drain holes in the rear of the outer coaming.

The first step in building these was to make and install the inner coamings. These are 3 1/2 inches high and made of two layers of laminated 6mm ply. The first layer was screwed into the sides of the deck stringers that run under the decks parallel to the hatch openings on each side. The second layer was laminated on from the outside and filleted to the adjoining deck surface. This makes for a very strong and rigid inner coaming.

The front and rear pieces were then fitted to the adjoining sides, with epoxy fillets in the corners to reinforce them. After the clamps were removed, epoxy fillets were made all the way around to the decks, then the outside corners were rounded off to a nice radius with a belt sander.

An overhanging lip of 6mm ply cut to 3/4 of an inch in width was epoxied on the top edges of the coamings. The extra 1/4 inch of overhang is designed to further aid in turning away water that might otherwise squeeze between the top of the coaming and the hatch cover.

To insure that the hatch lid lies completely flat on the coaming, I sanded across the finished coamings with a rigid longboard to take down any high spots and keep everything level.

The hatch lids were then built using 9mm ply and an outer, overhanging lip of 1/2-inch ply to match up to the outer coamings. These hatch lids are larger than the inner coamings by about 3/4 of an inch all the way around, to allow for a channel between the coamings where any water that gets in can be contained and then drain away.

The first step in building the outer coamings was to align the hatch lid over the opening and then carefully mark the locations of the two outer side pieces. The installed outer sides of one of the outer coamings is shown here. The extra length will be trimmed when the athwartship pieces are fitted.

Here is how the hatch lid fits over the coamings. When closed the flat panel of the lid will rest on the top of the inner coaming. The outer lips of the hatch lid will mate with the top edges of the outer coamings all the way around.

Fitting the front and rear pieces of the outer coaming was the most difficult part of the job, as the bottom edges of these have to match the deck camber and the fore and aft placement of them has to exactly match the locations of the hatch lid overhangs. Here is a view of one of the rear pieces. You can see the drain openings cut at each rear corner. These are the lowest spots on the coaming and being to the rear are less likely to get wave action forcing water through them.

This is the other rear outer coaming. I installed both of these today, so now the hatches only lack the forward pieces before they are complete. When finished, the hatch lids will be attached using stainless steel piano hinges along one side and a locking latch on the other. All of this is a lot of work, but it will be nice having these large storage holds that are both dry and lockable.

I'm heading to Florida tomorrow to help David show his Tiki 30 at the St. Petersburg Strictly Sail Boat Show. I'm looking forward to a few days of hanging out on a boat, particularly a Wharram, and talking to people about sailing, boatbuilding and design. Reuel Parker will be there as well, so I'm sure that after a good dose of inspiration from him and David, I'll be ready to get back to work on Element II.

Monday, October 13, 2008

Sailing On Beat's Tiki 38 in San Francisco Bay

I almost made it to the launching of Beat Rettenmund's Tiki 38, Aluna, back on September 21, as David Halladay of Boatsmith had a big job going at nearby Bay Ship and Yacht in Alameda and I was invited to help. That trip didn't work out, but as it turned out there was some additional work to be done on the job a week after David took his crew back to Florida, so he asked if I could fly out and meet him to help out for 2 or 3 days. This time I was able to make it happen and I'm glad I did. Not only was the project last week at Bay Ship and Yacht an interesting learning experience, but I also got a chance to meet Beat and go for a sail on Aluna.

Aluna is the first Tiki 38 I've seen up close. It is a big boat compared to the Tiki 26 or even the Tiki 30. Beat has done a fine job of building her and Aluna is beautiful without the flashy high-gloss yacht finish many builders fret over. There are lots of nice artistic touches like the axe-shaped stemheads (see below) and the sunburst rays of non-skid applied to the decks.


Aluna has lots of slatted wood deck space and a protected steering station in the pod. Twin motor wells are fitted near the port and starboard hulls forward of the pod. You can see the open motor wells below. That's Beat sitting to starboard and David Halladay standing in the port motor well. At the present time Beat is using a couple of older model gas outboards for auxiliary power. He plans to switch to electric power as soon as he works out the details.

To go sailing in the bay, we motored out a long channel, straight into the wind and chop using the one functioning outboard. It sputtered and cavitated, but got us out to deep water, where at last we could shut it off and bear off on a reach under the unique crab-claw rig.


The crab claw rig requires a lot of fine-tuning and adjustment, and Beat still does not have the final version of the spars, which will be made of bamboo, nor sufficient turning blocks for adjusting the sheets. Despite this, Aluna quickly got up to speed off the wind, feeling much like the smaller Tikis I've sailed. Tacking and pointing into the wind did not go so well, but the rig is an experiment and will take some time to iron out.

It was a great afternoon sail and we were able to return to the dock without using the engine. I needed this, as it has been too long since I've been sailing and too long since I've been on the water anywhere besides the Gulf of Mexico. I'm back at work on Element II today, looking forward to that great feeling Beat must be experiencing now that he is enjoying his new creation finally in her element.


For more about Aluna, visit Beat's website here: http://web.mac.com/mobeyprod/iWeb/Alunatheboat/Welcome.html

Saturday, September 27, 2008

Fiberglassing the Foredecks

I've finished up the fiberglass sheathing of the foredecks and have started making parts for the forward hatch coamings. The fiberglass work was actually finished last week before the Boatsmith crew stopped by to visit, but I've since done some more fairing and filling work and have finished prepping the stern decks for their layer of 6-oz. glass cloth.

The first step in sheathing the decks was to get another layer around the sheer stringers, from the point where they join the topsides, wrapping all the way up to overlap the decks by about an inch and a half. This insures a good double layer of glass on the potential impact areas along the sheer and helps reinforce the deck to hull joint. To do this I taped off both sides of where I wanted to cut the glass strips and then laminated them on oversize, trimming to the tape with a razor knife after the epoxy cured enough so that the glass would not pull away.

The first two photos below show the wetted-out fiberglass overlapping the tape that defines the width of the finished strips:

After the edge sealing strips were cured and second coated with epoxy to fill the weave, the main decks were sheathed with the fiberglass overlapping the edge strips.

Again, masking tape was used to allow a neat edge to be cut at the overlap. After removing the tape and excess glass, the cloth was filled again with a second coat of epoxy thickened with phenolic microballoons and silica.

After the second coat of thickened epoxy had cured and was sanded, the decks looked like this. Final fairing will be done by adding more epoxy fairing mixture with a drywall knife and then sanding everything smooth. But before that is done, I will build the hatch coamings for the forward stowage compartments.

Boatsmith Crew visits the Element II Project

Thursday evening I had the opportunity to show Element II to my good friend David Halladay, and his entire Boatsmith crew. This unlikely visit out in the middle of nowhere in Mississippi happened because David and his crew were en route back to their home base in Jupiter, Florida, after completing a large teak deck project in the SanFrancisco area. Needless to say, they were worn-out from days on the road, so the visit was short, but the guys got to see the boat project I've been telling them about for so long, back before they built the first Boatsmith Tiki 30.

In fact, it was my project and this blog that finally pushed David over the edge back at the beginning of this year, inspiring him to build a Wharram cat as he had long wanted to do. The result was his fine Tiki 30, Abaco, documented on Pro-Built Tiki 30 and launched this year at the Mystic Wooden Boat Show. This all led to David's meeting with James Wharram and becoming the only licensed professional Wharram builder in the U.S.

Below: David Halladay, at right, with his well-trained crew of boatbuilders crowd into my tiny shed between the hulls of Element II. I should have flattened the tires on their truck so they couldn't leave. If only I could afford to pay these guys to help me finish up, I could be sailing before the middle of October!

David and the crew hung around about an hour and a half, inspecting my work and looking over the Tiki 26 design with interest. He's hoping to get started building another Wharram in Florida soon, and thinks the Tiki 26 could be a good seller, appealing to a lot of customers.

Likely the next time they see Element II it will be somewhere on the water in south Florida, as that will be one of my first destinations for my shake down cruises.

Tuesday, September 23, 2008

Decking the Sterns

The stern decks are now installed and I am in the process of fairing and filling them in preparation for fiberglass sheathing.

Before they could be permanently glued in place, I first completed the painting in the stern buoyancy compartments and the varnishing in the aft bunk sections. The inspection plates were installed in bulkhead No. 1 in each hull, as well as the thru-bolts that reinforce the aft beam lashing pads.

As in the bow buoyancy compartments, I painted the sealed stern compartments gloss white to make it easier to inspect the interiors with a flashlight. The natural finish in the aft bunk areas is actually a satin finish polyurethane with U.V. inhibitors. I think the satin finish will be nice in all the main cabin areas.

The decks were glued down using thickened epoxy on the deckbeams and along the sheer stringers. Temporary screws were used to hold them in place until the epoxy cured.

Once the epoxy was cured and all screws removed, I began the process of filling the screw holes and sealing the deck to hull joint with thickened epoxy. After this cured, I sanded the excess epoxy away and then used a small router with a 1/2-inch round-over bit to put a radius on the deck edges. This will make it easier to wrap the 6-oz. fiberglass sheathing over the sheer stringer to overlap the hull-side sheathing.

The decks were shaped and filled around the stern posts. After this initial filling is cured it will be sanded and more fairing compound applied to smooth it out.

Here are the stern decks where I left them at the end of the day today - mostly filled and faired, sanded, and coated with a first sealing coat of epoxy prior to fiberglassing.

I've also been doing some final fairing and sanding of the bow decks, getting them ready to fiberglass as well. This should begin tomorrow if all goes as planned.

Tuesday, September 09, 2008

Stern Decks and Starboard Cabin

The current priority in the construction is to get the stern sections of both hulls decked so that I can focus on finishing the cabin interiors. As with the forward decks, the compartments beneath them will be completely finished before the decks go on, so that once these sections are covered with decks they will be out of sight and out of mind. Completing entire sections like this is always a good feeling as I can then move on to other areas without having to think about this again.

Stringers of Doug fir were first cut to length and fitted in the deckbeam notches. These stringers all have radiused corners on the bottom edges where they will be exposed. They were held in place by temporary screws while I marked and cut the deck panels, which are made of 6mm plywood.

There are only three stringers supporting the deck in these stern sections, but their stiffness will be enhanced by large fillets bonding them to the underside of the deck panels. Combined with the sheathing of 6-oz. fiberglass on the top surfaces, this will make the decks plenty strong while keeping them lightweight.

Here you can see the assembled deck panels with the stringers glued and filleted in place.

Below are the completed stern decks ready for installation. All the parts have been sanded and second coated with epoxy. They will be installed later this week after I get the final coats of paint in the stern buoyancy compartments and varnish in the aft bunk areas.

The outer cabin side for the starboard hull has also been installed and filleted to the shelves and bulkheads.

There will not be as many built-in fixtures as in the port hull. In addition to the panels for the electrical switches and the VHF radio and other instruments, there will be a removable chart table that will span across the navigation station and a hinged seat back that will allow comfortable seating at the chart table. Companionway steps identical to the ones in the port hull will be built on the inboard side.

Sunday, August 24, 2008

More Deck and Interior Progress

Work is ongoing on the port and starboard cabin interiors, as both forward decks have now been on for several weeks and the plan is to work my way aft with completing the main interior areas and then making and installing stern decks. The port hull is still a bit ahead of the starboard, as can be seen below. Here the galley sink and shelves have been installed and the outboard cabin side is filleted in place. Only a small amount of cosmetic filleting remains to be done in this area.

Here's a view looking into the port galley hull from the area where the companionway will be. Another small shelf will be added on top of the middle stringer on either side of the sink, to utilize an otherwise wasted space. The companionway steps are also installed but not visible from this angle.

Here's an exterior view of the port hull with the outer cabin side installed.

From this angle you can see the plywood portlight trim rings and how they have been filleted to the cabin side. These will be fiberglassed over right along with the surrounding surfaces. The Lexan will be fitted from the inside with matching trim rings to hold it in place.

Below is a view of the port foredeck just after installation. The temporary screws have been removed and the holes filled with epoxy.

Here's the starboard foredeck after fairing and pre-coating with epoxy. The decks will be fiberglassed next and then the hatch coamings will be built.

Inside the starboard hull I'm working on the layout of the shelves and panel faces that will house the 12-volt switch panels, battery voltage monitoring meter, VHF radio, SSB receiver, stereo and an AC inverter.

Most of these items will be mounted under the shelf in the companionway area of the hull, where you can see the open vertical framing here.

Removable panels of teak-faced 6mm ply will be screwed to the outside of this vertical frame. The instruments will be fitted in the removable panels, and all wiring organized inside under the shelf and accessible by removing the panels. Now that these sheer-level shelves have been fitted in the starboard hull, in the next couple of work sessions I can finish and install the outer cabin side.