Sailing in Maine

Sailing in Buzzards Bay

Tuesday, November 25, 2008

The Sail Plan

Click on any image to enlarge it. Blog starts with 9/23/08 post.

The original Yakaboo carried a very good looking batwing yawl rig. This is an efficient sail shape (like the elliptical shape of many airplane wings) that allows many options to shorten the amount of sail area to suit prevailing conditions. As much as I would like to do a rig like this (and may in the future) I just can't take the time if I want it done by vacation.
I started looking for suitable alternatives, perhaps a lug yawl rig for its ease of construction and simplicity.

Looking around on the net, I came across this nice lug yawl set-up. It turns out that these sails were made by Todd Bradshaw of Madison, WI, author of Canoe Rig: The Essence and the Art : Sailpower for Antique and Traditional Canoes. I contacted Todd to inquire whether he would make a similar set for me, and how soon. I also sent away to Amazon for a copy of the book.

After supplying Todd with information on the boat and its intended use, he sent some illustrations showing the proposed sail rig. He suggested going with higher-peaked sails, which will shorten the length of the boom (to keep it from hitting the water when the boat heels), and to improve windward performance. He also suggested raking the masts 5 or 6 degrees.
In place of reef points to reduce sail area, there will be three mast steps to be used with a 39 sq. ft. main and a 15 sq. ft. mizzen. Most of the time, both sails will be used with a total area of 54 sq. ft., then either the main or mizzen will be stepped by itself when the wind pipes up.
The higher peaked sail means the main mast will be too long to stow in the cockpit, but I'm willing to make that trade-off to get better performance.
Defining the sail rig is necessary before the decking is installed because I need to locate the front mast step while it is still accessible.

Wednesday, November 19, 2008

Installing the Rear Deck

Click on any photo to enlarge it. Blog starts with the Sept. 23rd post.

While I was at Jamestown Distributors to pick up supplies, I bought a pair of stainless steel eye bolts with 1/4"-20 threaded shafts to serve as rudder mounts. These were mounted on the rear stem prior to the deck installation.

One of the remaining sheets of ply was placed over the back half of the canoe and the outline was traced with a pencil.

Another view.

I cut a half inch (12 mm) outside the pencil mark.

Test fitting before applying the epoxy.

I used a special marking stick to locate the position of the screws that will hold the deck in place until the epoxy cures.

After removing the deck, I applied an epoxy/ sawdust mix to the stringers. The deck was reinstalled and clamped in place. As they say, you can never have too many clamps....

The outside edge was secured with #8 x 1" brass screws. The holes were pre-drilled with a countersinking bit.

The deck in place with screws installed. No screws were installed around the cockpit.

Wednesday, November 12, 2008

Installing the Deck Stringers

(Click on any picture for larger image. Blog starts with 9/23/08 post.)

After installing the bulkheads and inwales, it was time to add the stringers that will support the deck. I used 3/4" x 3/4" douglas fir for the main deck stringers and the inner deck stringers. Cedar would have been lighter but I decided to go for the extra strength of fir.

The rear bulkhead and side deck supports were notched to receive the stringers. I could have had the stringers come together to form a "V" at the deck beam, but I decided to leave them slightly apart for added passenger room. I have found that since I'm building without a plan, I've had to take extra time to work out this and other similar design decisions. Plans cost money but they allow you to work faster since you don't have to design all the parts as you go along.

The interior is starting to take on a finished look. It doesn't show in the photo but there is a nice texture on the floor. I'm glad I won't have to paint the interior of the boat.

View from the bow.

I applied a layer of fiberglass cloth to the stem. The notches in the bulkhead are visible here. In the center, only the pine stiffener was notched for the main stringer, the bulkhead was not cut through here.

The entire interior has been given a coat of epoxy in preparation for the installation of the deck.

Sunday, November 9, 2008

Installing Bulkheads

Click on any image to enlarge it. Blog begins with Sept. 23rd post.

At the bow and stern, I applied 3" (7.5 cm) wide fiberglass tape and epoxy over the seams not already covered with fiberglass cloth.

The two bulkheads were put in place and aligned to the basket mold with boards and c-clamps (bow shown here).

I used a mixture of sawdust and epoxy for added strength on the side of the bulkheads that will be covered by the deck and will not be seen. On the cockpit side, I used the wood flour/ silica filler for color matching. It is also much easier to apply smoothly and needs less sanding.

The rear bulkhead before being epoxied in place.

The bulkheads were set 97" apart, which will allow an 8' (240 cm) long double paddle to be stored inside the cockpit.

Deck supports were cut from the plywood that won't be used for the deck. Each support was made from two pieces glued together for added strength (in case anyone sits on the deck).

The notches in the bulkheads were sanded to the size of the inwales.

Each inwale was made from a sixteen foot long piece of 1 x 1" northern white cedar. I chose cedar for light weight and flexibility.

The pencil line shows where the inwale will be cut to fit next to the rear stem.

The deck supports were given a circular cut-out with the Roto-Zip tool. I used "L" brackets to hold them in place in the hull while the wood flour/silica/epoxy mixture was applied. The radius on the top of each pair of deck brackets was taken from the information provided by the Hulls model.

I want the deck to be wide enough so that if the canoe gets knocked over by a strong wind, it will float on its side without taking on any water. They should also be wide enough should anyone want to sit on them.

After the deck supports set up, I glued the inwales in place with a sawdust/ epoxy mixture. I set them about 1/4" above the shear line so that they can be planed to the proper angle to receive the deck.

The hull is now considerably stiffer with the inwales in place.

I glued a 1/2" thick pine stiffener to the top of each bulkhead. This should give enough surface for gluing on the deck.

This is the rear bulkhead.

View from the cockpit side.

At the bow, a brace was glued in place where the front of the cockpit opening will be. I plan to have a mast step at this location, so the extra strength is needed.

I glued plywood rings to the bulkheads to give the access hatches extra thickness for mounting screw attachment.

Wednesday, November 5, 2008

Glassing Inside the Hull

(Click on any picture to enlarge it. Blog starts with 9/23/08 post.)

I ground down the epoxy fillets using a 6" sanding disc mounted in a drill, and a 5 1/4" random orbit sander. I plan to have a natural finish inside and out, so I spent some time here.

After sanding, the inside of the hull was coated with thinned epoxy.

I set 6 oz. fiberglass cloth inside the hull stretching from in front of the front bulkhead (at the 4' mark) to beyond the rear bulkhead (at the 12' mark). I applied one coat of thinned epoxy, since I did not want to fill the weave but leave a textured surface. This cloth will supply the strength needed to support the passengers without any added stringers in the hull.

This shows the cloth (on left) after the single coat of epoxy was applied. The fiberglass has disappeared and the wood grain shows through nicely. The fiberglass butt splices used to join the plywood sheets are hardly noticeable. There is a nice texture on the surface. I lucked out here.

The bulkhead will go just inside the edge of the cloth.

A view of the hull at this stage.

Another view of the hull. The lines are nicer in 3D than the model would suggest.

I marked out the two bulkheads using dimensions taken from the Hulls model. I located the bulkheads on areas of the plywood that will not be used for the deck.

I am going to install 8" hatches in the two bulkheads.

Finally, I have a chance to use the circle cutting attachment that came with my Roto-Zip tool. What a neat toy.

A perfect circle. How cool is that?

The completed bulkheads. The notches are for the inwales.

Monday, November 3, 2008

Gluing the Hull

After all the seems were tight and free of gaps, it was time to start gluing the panels together. My "formula" for making color matched glue fillets that are easy to apply smoothly, is to add equal parts System Three wood flour and System Three silica thickener to the West epoxy mixture. I also added a very small amount of Okoume sawdust for color. Usually I mixed 3 squirts of epoxy, 3 squirts of hardener (from the pumps on the cans), 3 spoonsfull of wood flour, and 3 spoonsfull of silica. These both contain nano particles, so I always use a good respirator when working with them.

I spread this mixture in between the stitches, just enough to hold the panels after the stitches are removed.

At the rear, I added a 3" (75 mm) radius to the lower rear corner of the hull.

I made a rear stem from a piece of 3/4 x 1 1/2" (19 x 38 mm) mahogany. I tapered it at the rear to match the angle of the hull panels, and at the bottom it was tapered to a point. This stem will give the rudder a solid mount.

View of the bow after the stitches were removed.
I used a random orbit sander to round it to a smooth curve.
The bow is designed to have good reserve buoyancy to keep it from diving into waves, while having a high forefoot to allow it to tack easily. It's a tricky trade-off.

After the initial epoxy application cured, the stitches were removed. I ground down the high spots with the sander, then added more filleting mixture to cover all of the seams.
After the seams are sanded again, they will be ready for the application of fiberglass cloth.