Construction

Small boat construction usually begins with building a "strongback" to support the frames. For this boat, I decided to build a plywood platform that the frames could be secured to.

The platform was framed in 2x6's, and topped with 3/8" plywood.

Then the frames were built. First, a set of plywood templates were cut from 3/8" plywood. The templates provided the full scale lines for each frame, but were extended on the bottom so that they would sit at the proper height on the base.

The frame parts were cut from 1x6 premium (no knots) pine from Home Depot. These were given 2 coats of epoxy, then bolted to the plywood templates.

Plywood gussets were cut from 3/8" plywood and epoxied to the frame parts.

Gussets were applied to both sides, and shaped to the outline of the frames. The frames then got a final coating of epoxy for sealing. At this point, the templates were cut down a couple of inches on the top and sides, so that when the frames were bolted back to the plywood templates, the frame would extend at least an inch or two past the edge of the template - allowing construction of the boat without anything being permanently attached to the templates. The templates could then be unbolted and removed from the rest of the boat once the boat was righted.

Here's a picture of the frames, bolted to the templates, with the templates shimmed and bolted to the "strongback" platform:

There was a lot of fidgeting and sweating that went on at this point. I cut a couple of 15' long, skinny battens that could be bent around the frames. The plans called for 3/4" chine pieces. I used fir for the chines and sheer strips, because that was the best clear wood that I could find in a 16' length. I very quickly determined that there was no way I was going to be able to bend a piece of 3/4" fir to the shape demanded by the curve of the bow of the boat. The only way to accomplish this was to rip 3/8" pieces that could be laminated in place to form the 3/4" chine and sheer logs.

The keel was a similar story. The only way to make the forward curve of the boat was to laminate the keel of thinner strips. The forward section of the keel was laminated of about 6 strips of 3/8" fir. A notch was left several frames back to allow a solid piece of fir 2x4 to be epoxied in for the after 8' or so section of keel.

The picture above also shows the stem piece that was fabricated and added in. The directions called for a curved stem that continued the arc of the keel. I went with a straight stem. The frames were notched to receive the stringers. I used small angle brackets of 1/8" aluminum to at first clamp, and later hold the stringers in place.

Additional stringers were added to provide more support for the bottom panels. Note that the notches cut for all the stringers were OVERSIZED on the length of the notch. Depth was cut to allow the stringers to sit flush with the line of the frame. But extra width was given to allow a "limber hole" so that water could pass from the front to the back of the boat. There will always be water inside a boat. You better allow a way for it to get to the BACK of the boat so that you can drain or sponge it out. The limber holes ensure that water doesn't accumulate at the frames and rot out the structural members of the boat.

Next, the sides were fabricated. Panels of 1/4" marine grade plywood were cut to a very rough shape. Since I only had 8' plywood, and the boat is ~14 feet long, it would take 2 pieces. The two panels for each side were rough cut, and laid out on sawhorses.

The debate rages over whether long pieces should be joined with "scarf" joints or butt joints with a butt block behind them. While my brother is an excellent craftsman, *I* have never been able to successfully make a scarf joint that I thought would be strong enough to work. So for this boat, I decided to use butt joints. However - I did it a little differently - I used xynol fabric (xynol is a polyester fabric that can be used instead of fiberglass cloth - more on xynol later) over the butt joint instead of another piece of wood.

Several 2x4's were laid on sawhorses to support the panels. Plastic covered the 2x4's to prevent gluing the panels to them. The panels were then clamped in position, coated at the joint with epoxy, a section of cloth laid over it, followed by another layer of plastic, and then a 1x8 clamped over the seam. This meant the epoxied joint in the 1/4" plywood panels was clamped securely between a 2x4 on one side and a 1x8 on the other, ensuring that the thin 1/4" edges would be in alignment.

Once the cloth, saturated with epoxy, cured and was given a second filler coat of epoxy, the whole assembly was carefully turned over so that a "butt-strap" of xynol cloth could be added to the opposite side. Fully cured - using cloth on both sides of the butt joint provided a very strong full length panel. I still had the 1/8" or so thickness of cloth that would have to be faired, but this was much easier to deal with than a scarf joint, and didn't leave the huge thickness of wood that would be needed for a traditional butt joint.

The panels were given 2 coats of epoxy inside and out before being attached to the bottom of the boat.

NOTE: I mention using "xynol" here instead of traditional fiberglass cloth.

After reading about xynol on the internet, I decided that was what I wanted to use.

Xynol is a polyester fabric that can be used instead of fiberglass. The two primary advantages are that it conforms better to tight corners, and that because it is made of polyester, there are no glass fibers to get in your hands, lungs, or other places... You might still want to use a mask to avoid the dust when sanding. But you can sand xynol coated edges and surfaces with bare hands with no fear of the glass itch you get with fiberglass. There are debates on the relative strength. But in my work, xynol has proven plenty strong for covering surfaces. It's easy to work with, and wonderful when it comes to getting it to take the shape of the complex curved surfaces on a boat. The Thompson that I refinished was also covered with xynol. In that boat, the sides were lapped - meaning the xynol had to conform to the edges of the lapped planks. Fiberglass NEVER would have worked for that!

Anyway, back to Mischief. Here's a picture of the boat with sides added:

This picture shows the laminated transom glued into place as well. I wanted a transom of SOLID wood (not plywood), as I'd had problems on a previous boat with plywood wicking up water from the bottom of the boat and rotting. So for THIS boat, I went to Lowes and got a couple of pre-fabricated panels of aspen boards. The panels are made of glued up strips of 3/4" boards. The panels were 6' long, and 2' wide. I sealed one of these in epoxy, covered with a layer of xynol, and then epoxied the second panel on top. This gave me a transom that was about 1.5" thick, with a layer of xynol in the middle. (The outside of the transom would also be covered in xynol with the rest of the boat - so while the wood itself wasn't fantastically strong, the resulting wood / cloth / wood / cloth sandwich would be more than sufficient. And just to be sure, this was capped with oak, and included an oak inner board to distribute the motor clamping stress, and an interior fir frame support screwed and epoxied to the inside of the transom - oh, and 2x6 gussets in each corner, along with the attachment of the 2x4 fir keel and all those stringers. Yes, I've been accused of overkill in the past...)

The bottom panels of the boat were butted together just like the side panels, and also coated with epoxy inside and out (you can't get to any of these corner places once the boat is put together, so everything has to be sealed as you go - part of what makes building a boat take so long...).

The bottom panels were to be of 3/8" thickness to give more strength than the sides required. The bottom panels would be taking the brunt of the force as the boat lifted over one wave and smacked down onto the next one. So it had to be strong.

Unfortunately, as with the stringers, 3/8" marine plywood simply wouldn't make the curve at the front of the boat. So I cheated. While at the lumberyard, I found something called "bending luan". It comes in 3/8" thickness, and has all the grain running transverse, instead of along the length of the plywood. This allows it to bend almost like a sheet of cardboard.

The bottom panels were assembled with 3/8" marine plywood for the back 8 feet, and bending luan plywood for the forward remainder (about 6 feet). The bottom panels were butted together with xynol on both sides of the joint, just as the side panels had been, and then coated with epoxy - lots of epoxy and attention on the luan part, since it was clearly not as strong as the marine plywood.

The bottom and side panels were epoxied to the boat. Screws were used to hold the panels in place as the thickened epoxy dried. But after the epoxy cured, the screws were removed. The theory here was that the epoxy joint should be stronger than the screws, and that I didn't want the screws left in the hull to rust and then leave voids for water to accumulate and rot structural members. The other reason for removing the screws was so holes for future pieces could be drilled without worrying about hitting a buried screw (i.e. when the decking and rub rail was to be installed). For the next boat, I'm probably going to leave the screws in for the extra strength.

After the side and bottom panels had been attached, trimmed, and sanded, it was time to start applying the cloth. The transom was first so that the edges would be covered by the bottom / side sections of cloth:

A single width of cloth would reach from the center of the boat, over the edge, and cover the side. This allowed for an overlapping seam on the bottom - more strength at the keel, and an easy place to fill. The bottom wouldn't be seen as easily. Again, xynol cloth was used. The first picture is with the cloth laid over the hull.

After the cloth is wetted out, and before trimming:

The filling and sanding (and filling, and sanding, and filling, and sanding, and...) takes a LOT of time. Fortunately, I wasn't run out of the neighborhood by neighbors complaining about the palm sander, but I'm sure they were REALLY glad when this part of the project was complete. There are those that think a cloth / epoxy coating adds too much weight to a boat. I really don't understand that argument. In total, I used about 8 gallons of epoxy on the boat. Probably 20% or more ended up on the garage floor as sawdust. Compared to the mass of the motor and battery, the total weight of the rest of the epoxy just isn't that much. And I really don't think epoxy gains weight as it dries...

I used Silver Tip Series Quick Fair from System Three to complete some of the filling and all of the fairing of the cloth. Quick Fair is like Bondo for boats. Of course, it comes at a respectable "boat" price. The argument is that since it's epoxy based instead of resin based, it's MUCH better for fairing work on a boat. Hmmm... Marketing? Anyway, still seems like more of this ended up as sawdust than on the boat - but that's the way it goes.

FINALLY the time came to start painting. I've made the trips to the bank before on other projects so that I could buy Interlux paint from West Marine. It's truly good stuff. However, for this project, I just couldn't justify spending that much money for a quart of paint. I had recently used Rustoleum paint for a project, and found it to also be very good. Reading the label, it seemed to be just as compatible with the epoxy surface covering everything. And it was MUCH cheaper! The strange thing was that instead of Home Depot and Lowes, which only carried a few colors, I had to go to WalMart to find the blue I was looking for. Mischief is graced with "Gloss Sail Blue" paint from Rustoleum:

With the painting completed (more hours of sanding, painting, sanding, filling, sanding, painting....) - it was time to flip the boat:

The help of a sometimes less-than-enthusiastic teen daughter, along with co-workers and friends easily accomplished rolling the boat. It would come to rest on a carpet covered pair of bunks screwed together with cross beams, complete with casters. This would allow me to roll the boat back and forth in the garage for easy access.

In the above picture, you can see the plywood frame at "station 4" that was intended in the plans to be part of the bench seat structure. After playing with several attempts at how to build that seat, I finally decided to remove the bulkhead and use back to back seats.

The time had come to start the interior work in earnest.