Sunday, May 13, 2012

More Cockpit Details

My focus for the past week has been on getting the structure of the cockpit finished so I can fit the seats/hatch covers for the storage compartments and finish the glassing and fairing of the interior of it.  One important consideration in the cockpit is working out the boat's electrical system and providing for wiring between the two hulls and to the mast.  The house batteries will be mounted in the starboard stern cockpit locker, adjacent the navigation station in the starboard hull, where there will be a 12-volt switch panel to control all circuits on board.  To get the wiring from the cockpit into the hulls while still keeping the boat demountable, I'm using David Halladay's method of PVC pipe stubs glassed into the cockpit compartments and hull sides, with rubber inner tubes and hose clamps sealing out the water.  More on those connections later.  First, I had to work out getting the necessary circuits from the starboard side of the cockpit to the port side, as well as to the mast foot for those wires that have to go to the masthead.  Here is the sawn 2-inch PVC pipe I'm using for that, glassed into the joint at the top of the slope on the forward end of the cockpit:

You can see the hole going into the port side cockpit compartment, and the cut-out at the bottom that will be the exit point for the masthead wiring.   Here, I've held it in place with pressure from a couple of 2 x 4s clamped in place while the fillets dry:

All the PVC wire runs will be glassed over, faired into the adjacent surfaces and painted, but after gluing this one in, I had to move the cockpit to the boat to check some other dimensions.

The slot in the bottom of this wire run will be further protected from water entering by the addition of this compass housing I've built to mount my lighted steering compass.  This compass was salvaged off the wreck of my destroyed monohull, Intensity, and somehow came through Hurricane Katrina unscathed.  It will be a nice addition to Element II:

While I had the cockpit in place hanging from the beams, I went ahead and made four teak locating/hold-down blocks for the four corners of the cockpit.  You can't see them completely here, but each block is L-shaped, so that it not only locks down the cockpit to prevent it from lifting, but all locks the sides to prevent lateral movement:

The next step is building the coamings for the cockpit compartments and finishing the side deck pieces that span the gap between the cockpit sides and the hulls.  Here you can see the starboard side deck in place:

These side deck pieces will be removable for installation of the cockpit when the boat is assembled.  I've worked out a design for the compartment lids/seats, in which they will be permanently hinged to these side decks, reducing the weight of the cockpit for transportation and facilitating a faster assembly time.  More on the details of this when I get them farther along:

Here's a overview of the cockpit with all these various additions.  Looking forward:

And looking aft.  Note also the two rails that span the gap between the aft beam and the net beam.  A boarding ladder will swing down between these, and trampolines will fill in the gaps on either side:

Here's another view of those ladder rails from astern:

The cockpit is now back off the boat and I've finished fitting and gluing in the coamings for the hatches over the storage compartments:

Here are those side deck pieces again, temporarily clamped in place.  They will fasten to the outer coamings like this in actual assembly, the outboard edges resting on the support rails glassed on the inboard cabin sides of the hulls:

Cockpit and Motor Mount Measurements and Details

A reader and fellow Tiki 26 builder wrote the other day to request some measurements on my cockpit clearance above the waterline and the depth of the prop of the Nissan Extra-Long Shaft 6hp outboard.  Because the cockpit is slightly deeper than the 9 inches shown on the plans, he was concerned about wave tops slamming the bottom, and also wanted to make sure the prop was deep enough to avoid cavitation in a chop.  I had to reinstall the cockpit the other day to make some other measurements anyway, so I shot these photos showing the requested dimensions.  I made up for the two-inch extra cockpit depth somewhat by making my beam mounting blocks on the deck thicker by almost that amount.   I don't think clearance will be an issue, and with the extra-long 25-inch shaft, the motor can be mounted high in the cockpit to protect it, yet it will still reach deep enough so that it will almost touch bottom if the keels of the hulls do.  This first shot shows the depth of the cockpit hanging below the aft crossbeam:

Here you can see can see the depth of the prop, again measured from the bottom of the aft crossbeam:

The bottom edge of this piece of 2 x 4 lumber is in line with the bottoms of the keels adjacent to the motor.  As you can see, the prop can't hit bottom before the boat runs aground, as the deepest part of the keels are slightly forward anyway, in the midships portion of the hulls:

This last shot shows the 2 x 4 at the approximate average load waterline.  The bottom paint is probably 3-inches above the true waterline to allow for heavy loading at the start of a voyage.  As you can see, with the extra-long shaft, the prop is unlikely to come out of the water in anything but the worst conditions:

Sunday, May 06, 2012


I'm in the process of painting various parts at the moment.  Here are a few photos of the crossbeams.  This first shot shows the aft beam and the additional net beam.  You can see the holes that have been drilled in the trampoline rails for the two rear tramps.  I've also worked out the details on the aft ladder and have just finished building and glassing the ladder support rails.  The two small blocks you see near the center of each of these aft beams are chocks to lock these support rails in position.

The other beams have been pained as well.  In addition to my own beams, in the shed next to the boat I have another complete set that I am glassing and fairing.  I built these on contract for a friend who has a Tiki 26, along with new rudders.  I'll post photos of those parts soon.