Monday, June 29, 2009

The Texas 200

Earlier this month, Dan St Gean and Brian Rugg entered the second annual Texas 200 (cruise/raid/race/survival course?). Their entry was a marriage between two Tamanu hulls and the frame and rig from an aging Hobie 18. You can read the story of the hulls construction here.

Many adventures ensued and you can read a full account here.

Sunday, June 21, 2009

Ulua with safety ama

Martijn van Nugteren in the Netherlands has his stretched Ulua ripping along in fine style. This foam composite Ulua is rigged like the Hawaiian racers with a safety ama that doesn't touch the water until the canoe is heeled as much as you see in the above photo.

Tuesday, June 16, 2009

A nose cone for a PVC pipe ama

Two years ago when I built my first PVC pipe ama in Fiji, I made the nose fairing out of a solid piece of fence post. I shaped it with a cane knife and a block plane. It performed well enough and didn't leak, but I didn't like the weight of it out on the tip of the ama.
This time I have prefabricated a foam and fiberglass nose cone that I will carry in my luggage.

The nose cone is built in the same way as a complete foam and fiberglass ama with a central plywood web and foam blocks glued to both sides with polyurethane glue. You can use either ESP beaded white foam or the blue or pink Styrofoam sold for insulation.

I did the rough shaping with a handsaw and electric hand plane. The final shaping is done with a sanding block.

About four inches of the cone is recessed to fit inside of the PVC pipe. Both the recessed area and the rest of the cone is shaped down to allow for the thickness of the fiberglass and fairing compound. I allowed about 1/8" or less for this.

Here the foam is fitted inside of a short section of 6" PVC drain pipe to check the fit.

The 9 oz cloth fiberglass is applied (with epoxy resin only!) from two sides allowing a double thickness overlap along the top and bottom. I used small round patches of fiberglass on the very tip where it is difficult to get the fiberglass to stay tight against the foam.

After the epoxy has cured, I applied fairing compound with a putty knife.

After final sanding of the fairing compound, the nose cone is ready for installation into the end of the PVC pipe. It will be held in place with a flexible adhesive sealant like Sikaflex or 3M 5200. Silicone will work if you cannot get the polyurethane sealant.

Tuesday, June 9, 2009

Fiji here we come

Two years ago my wife and I stayed in Fiji for a little over two months. I built the first of my Tamanu designs there and we had the time of our lives, sailing, fishing, and exploring.
Two days ago I shipped a 2 HP Yamaha outboard and a folding anchor to Fiji to be waiting for us when we arrive in early July for a three month stay. Since the original Tamanu was sold, I'll be building another on a different island. It takes about two weeks, if all goes well, to get the hull and ama finished. Excellent marine plywood is manufactured there, but my suitcase will be full of fasteners, polyurethane glue, hardware, and sails. I won't be using any fiberglass or epoxy resin. I'm trying to use as many locally available materials as possible. Cheap Chinese power tools are locally available and will last at least as long as the project.

I'll be building the same basic hull shape this time with some differences only with the deck and bulkhead layout. The ama will again be 6" (150mm) PVC pipe with a foam/fiberglass nose cone that will be in my luggage. The Rakiraki area where we will be staying is known for its high winds and is a favorite kite/wind surfing location. I'll be trying a traditional sprit rig this time because it is more easily reefable than the stub mast rig I used last time. I have a smaller triangular sail for really windy conditions.
The photo below shows the sprit rig I used this past summer on my 24' Wa'apa.
Hopefully I will be able to update this blog occasionally during our stay.