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Time to start a new project, the Sea Knight

I have been rather quiet for the last couple of years, but I ended up really enjoying my canoes.  I built two more canoes after the one I blogged about here, one for my wife and one for my brother.  I also converted the canoe building form into a cat play/scratching tower that they absolutely love.

During the last couple of years of enjoying my canoes and all the new places I could go and do with them I continued to ponder what my next project would be.  Building the canoes was really enjoyable and rewarding (still is everytime I go out in one of them), and it really wet my appetite (excuse the pun, more to come)to do something more, something bigger.  I live in the Pacific Northwest and there is so much to see here by boat.  So I started to scour the intenet, my Wooden Boat magazines and the boat shows to see what was out there.

I ended up waffling between two designs, one a sailboat and one a power boat.  They are both trailerable and both are built out of sheet plywood and most importantly can be built by an amature.

Thistle 1040 - Bow tank bulkhead

bow tank bulkheadI installed the bulkhead for the forward bow tank today. All fiberglass Thistles have an air tank in the bow to help with floatation. Most wooden Thistles have giant foam blocks that are not as effective. To be self-rescuing, Thistles need as much floatation as possible. My #1 reason for installing the bow tank is to give the boat as much floatation as allowed by class rules to make the boat safer.

Below I'll post a photo of the tank I installed in Thistle 1014. This one will be similar. The class rules say that all parts of the tank must be 14" below the height of the sheer. The tank must also be forward of the stanchions. These limits determine the maximum size of the tank.

Thistle 1040 - Plugging away...

rail plugsI now have both rails on, plugged and sanded. The outer rail came from long piece of purple heart that was salvaged from another boat project and was going to be discarded. It was too nice a bit of wood to not use. The only problem it had was that the screw holes had been pre-drilled by a drunken novice (not me... really...) and at least one hole on each side was so far from the center line of the wood that they were unusable. Making old usless things new and beautiful though is what this project is all about and I manged to salvage the nice purple rail and it looks great. 

This photo shows a rail that has just been plugged after being belt-sanded flat. This was a salvaged piece of wood remember so that's why you see some of the top edge already rounded. After the plugs dry and are sanded smooth, I used a 3/8" round-over bit in my router to round off the edge. I'll post a photo later of the finished rails as they're looking great!

Some tips on plugging screw holes:

Thistle 1040 - One rail on...

Today I installed the port side rail. It's made up of three pieces of mahogany laminated to create the inner rail and one piece of purple heart for the outer rail. In this photo, you can see how the rails are leveled by clamping to a crossmember while gluing. Both rails are installed about 1/16" proud so they can be belt sanded flat to the top of the hull skin.

The inner rail is fitted first to match the tumblehome of the Thistle hull sides. Then the outter rail is fitted and they are ready to glue up togehter. Some people wait to attach the outer rail until the outside of the boat is glassed but I like to bond the rail directly to the hull skin and glue them up together at the same time. The inner rail is held in place with a few screws from the outside of the hull and then longer screws are used through the outer rail to pull everything tight.

Thistle 1040 - Interior sanded - Rails fitted

Thistle railI have both sides of the boat interior sanded. The first layer of epoxy and 3.7oz cloth is now smooth and ready for one more coat of Low-V epoxy but we'll have to wait until it's warm enough for the Low-V to flow out and level before it can be applied. That means it's time to start working on the rest of the new woodwork.

Time and Tools

With the frames, stem, and transom completed, I started working on the bottom of the boat, and found several jobs that my showood shavingsp is just too small for.  

 

I needed three twelve foot cypress one by tens.  The lumber yard was out of twelve footers, so they gave me fourteens.  I got them into the shop without sacrificing any light bulbs or windows, and laid them out side by side on saw horses.

 

After I cleared some space and moved the table saw, I had room to fit them over the jointer, but I made several passes and realized there was no way I could handle boards that long by myself.  Even with my girlfriend Sally helping, I couldn't keep the boards flat against the fence for the whole fourteen feet. 

 

Lines and Patterns

plottingThis is the half breadths of the body plan; the vertical line in the center is the stem of the boat, and each of the lines next to it are the profiles of the frames, or ribs of the boat, which double as the molds that the planks will be bent around.  I laid these out on half a sheet of masonite with a colored pencil, plotting points from the table of offsets.  These are the lines that I'll use to make the patterns for the frames and transom, and it looks to me like I won't know whether I hosed the job up or not until I'm putting the planks on the boat, which will be much too late. 

Once the lines were down, I laid the masonite on the floor and for each station, put nails on their sides at each plotted point, and then laid a piece of pattern stock on top of it and stepped on it, transferring the points to the pattern stock. 

What got me started

About a year ago, my girlfriend gave me a book entitled Wooden Boats by Michael Ruhlman (Penguin Books, 2001).  It was written about a boat yard on Martha's Vineyard that builds plank on frame wooden boats using traditional methods and materials.  That book completely captured my imagination.  It's not a how-to, but is mainly about the romance and beauty of wooden boats and the builders' reasons for choosing to build a type of boat that has long been almost completely replaced by fiberglass, aluminum, and modern manufacturing. 

Sanding 1/2 done...

I finished sanding the epoxy and cloth on one side of the boat and have one more side to do. This is tedious work and it seems to take forever to finish. The now smooth layer of epoxy and fiberglass cloth will get one more coating of epoxy but it will be Progressive's Low-V epoxy which flows and levels easily. This will be then covered with varnish or some other clear coat with UV inhibitor.

To make things more interesting, I started fitting one of the rails. The Thistle has some tumblehome in the starn and the hull flares out in the bow. That means quite a bit of shaping to get things to fit. Larry Ligget has a nice set of videos on Youtube showing how this is done. I'll embed part 1 below.

Sanding epoxy tips

I really like Progressive No-Blush epoxy and no, I'm not paid by them for this endorsement. I've worked with different brands of epoxy over the last 30 years and have developed a sensitivty to several of them. Not so with No-Blush. I also like the way it sands. Epoxy gets harder as it cures. Try to sand it too early and your paper will gum up and the epoxy will heat up and turn to gunk on your sand paper. Wait too long after the cure and it will be hard and difficult to sand. If you time it right, you'll have easy sanding without clogging and No-Blush seems to have a good two-week window where it's easy to sand.

Last week I sheathed the inside of my Thistle with 3.7 oz fiberglass cloth and epoxy. Before this can be varnished, it must be sanded smooth, first with 80 grit and then eventally up to 150 or 220. Areas in the boat that will get epoxy paint (right next to the keelson where the crew's feet go) will be painted and the rest of the boat will be left natural. The cloth will be transparent under epoxy and varnish.

Some general sanding tips:

Best Marine Epoxy

My favorite epoxy?

 

EpoxyUSA.com Progressive Basic No-Blush Epoxy

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