Move em out and roll em over

Sally and I rolled the boat out and a few neighbors came over to flip Skorpa back upside down so I can glass and paint the bottom. I cut the laminated stem flush and thought this made an interesting photo. You can see the inwales where they join the stem and the plywood hull panels meeting at the bow.

This is my second time flipping the boat so things were fairly relaxed.

Four of us were able to flip the boat with no problem.

When the four of us picked the inverted boat up to set it back on the frame we had the full weight which I think must be around 400 pounds.

A visit from the Designer

Graham Byrnes stopped by on the way between a boat show at Mystic and some boat building classes in Maine. He and Beth stayed a couple of nights with us. One of the reasons Graham stopped by was he wanted to see how I am coming along on my boat. No one else has built an EC 22. Graham has made several changes from the first EC 22, Southern Skimmer, so he has been following my build with interest. 

Graham said the boat was looking great.

He did notice a few places where stringers which stiffen the hull end abruptly at a bulkhead.

Graham referred to this as a pin joint.

Though the photos look much the same here the stringer continues right through the bulkhead.

This forms what is called a fixed joint. Much stronger. It is not always practical to continue the stringer through the bulkhead. You can taper the stringer and bring it to an end a few inches beyond the bulkhead.

Graham suggested that I place a fillet and some fiberglass around the area where the stringers end at a bulkhead. He thought that would distribute the stress and prevent any problems from developing.

If you look closely you can see a fillet and some fiberglass around the area of the stringer to bulkhead joint.

I was a little bummed when he told me about my pin joints but it did not take that long to patch them.

They look much better to me now.

Seat tops and bunks

The large piece of plywood I am working on forms the forward cockpit seats, centerboard trunk top, bridge deck and mizzen thwart.

I needed to cut out the openings for the foot wells and I thought I would try a different way of making the cuts.

 I am using a special bit in the router. The router bit has a small bearing on the tip. Once the bearing comes up against something solid it will not let the router cut any deeper.

This makes lots of dust and is kind of scary because you have to trust that the router isn't tearing into the centerboard trunk you spent three weeks building and installing.

 All in all very successful. The center board trunk emerged unscathed.

I survived as well. A router is an amazing and scary piece of equipment.

Marissa stops by for a visit

Graham Byrnes entered Woodenboats design contest for a fuel efficient 25 hp powerboat. He won with his design for Marissa. Graham took Marissa to this years Woodenboat Show at Mystic Connecticut. After the boat show Graham and his daughter Beth had a few days before they had to be in Brooklyn, Maine to teach two weeks of boat building courses.

Graham and his crew had burned the midnight oil to get Marissa ready in time for the boat show. There were a few details that had to be attended to before Marissa could be launched.

I drove Graham into Galilee and he bought some bolts and fuel line at Rhode Island Engine Company.

 Then he and Beth went to work.

Soon we were off to the boat ramp.

Cruising past the fishing fleet we headed for the breachway and the open water of the Harbor of Refuge.

Graham could hardly wait to open the throttle and see how Marissa will run. This is her maiden voyage.

Pretty smooth wake as we skim across the water.

Sally is sharing some local knowledge with Graham while Beth enjoys the ride.

After touring around for awhile we anchored Marissa on some sand flats and dug for quahaugs. We all enjoyed gathering the hard shell clams for our chowder. It was a late supper and a good day on the water.

Making an offering

All that framework is there to hold the 6mm plywood that forms the bunk tops and seat tops.

As you can see in the photo there is a lot of curvature in the hull up front. All that curvature makes fitting the bunks tops a bit of a challenge.

Making the tops out of as few pieces as possible keeps them light and strong. Meeting the hull on two or more sides is very tricky because if you have to do a little trimming you can end up making the panel too small.

To get around this problem I made a template out of a couple of pieces of scrap ply. That way I could individually fit each side until it was just right. Than I secured the two halves together.

Here I am laying out the pattern on my good plywood.

The result was a very nice fit.

I tried using cardboard to make a pattern and it works alright. The cardboard is a little compressible though so you do not get as accurate a fit as with the more rigid plywood.

 If the bunk or the seat top meets the the boat on only one side or on two adjacent sides you have it a little easier. You can get a rough fit and than use a block of wood and the side of the boat to scribe a line on the plywood. Plane down to the line and you should have a nice fit.

  Once you have the piece shaped to your satisfaction you can "offer it up" to the boat.

 

My boat has never accepted my offering the first time around. Sometimes after many attempts I just say that will have to do.

Joinery

The interior of an EC22 has a fair number of small parts that form a framework which functions to stiffen the hull and support the horizontal surfaces like bunks, seats and decks.

Most of these framing members are pretty light. Like 3/4 inch by 1 inch. Or under the bunks 5/8 by 1.

The framework is so light that you have to take care that the joints are as strong as possible without unduly weakening the framework.

 

 This is some of the framework that supports the bunks. I give each piece two coats of epoxy before I glue it in place. Epoxy loves to drip and run. Coating the pieces after they were installed could get ugly.

This is a butt joint. Simple to make, doesn't weaken either piece of wood, strong in compression, but weak in tension and in shear.

This is a mortise. Much stronger in shear, but you have to take a chunk out of one piece. It is not real easy to make the mortise.

I am not sure what this joint is called. I will call it a diagonal. I had not been aware of this method of joining wood until working on Skorpa.
At first I did not like the looks of it because it seems like the pieces could just slip apart under pressure.
Epoxy is pretty strong though and if it has some plywood on top to keep the joint from spreading than the diagonal is quite strong. Good in compression, tension and shear. Minimal weakening of the adjoining pieces and not too difficult to make.

I mark out the lines usually for 45 degrees. Saw cuts outline the sides and help control the depth.
A sharp chisel takes out the wood.

There are several variations on the basic diagonal.

These pieces will support the bridge deck on either side of the centerboard trunk.

Here we are under the port bunk. 4mm (1/8 inch) plywood webbing ties the hull stringer to the bunk framework. I use Mikes router to round off the underside of the framework.

View of the starboard bunk from above.

It is taking a long time for me to finish this boat. Yes I am having to learn as I go. I am trying to work carefully and do quality work. I also have a lot of other responsibilities to attend to.

Cockpit interior

What a strange word.

Cock Pit.

A depression in which roosters fight.

The location of many battles.

An open area near the stern of a vessel below the level of the deck from where the vessel may be steered.

I covered the floor of the cockpit with a layer of 2 ounce fiberglass cloth. This cloth is so light it does not add much strength. I have read that it adds significant resistance to abrasion without much additional weight, so I thought I would give it a try.


When the epoxy saturates the cloth it turns clear as glass.

Here the cloth has been wetted out and stringers have been glued in place to stiffen the hull.

This is a view through bulkhead # 4. You can see a piece of scrap wood holding the stringer in place while the epoxy sets up.

Looking forward from the Lazarette.


The Mizzen mast sits right in the middle of the cockpit.

The Mizzen mast step must hold the base of the mizzen mast securely. This rig has no stays. The mast step and the mizzen mast thwart have to bear all the loads placed on the mast.

The mast step is laying beside its intended location. There is so much force on this part Graham thought it best to use mechanical fastners (screws) in addition to epoxy to make sure the mast step holds.
Wherever fastners penetrate the wood moisture can find a way into the wood.
I drilled oversize holes and filled them with epoxy. Then I redrilled the proper size hole for the fastner.

Undoubtedly overkill for a boat that will be dry sailed, but what can you do?