Odda Sea - Life Aboard An Allied Princess Sailing Yacht

Sorry everybody: due to a huge influx of spam comments, I’m having to turn comments off for the site. Feel free to contact me directly, though!

Just a reminder, you can email me at my first name AT oddasea DOT com.


More updates to come shortly - been busy getting ALETHEIA ready for her first sea trials!

My blog buddy Bob over at Boat Bits is running a fantastic giveaway and all you need to do to enter is think for a minute.

The prize is the stunning DVD “Ice Blink” which I have yet to see but very much want to. So get in on the giveaway here.

That is all.


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In the previous installment on this subject, I covered the origin and general construction of a hard dodger for my boat.

The dodger in and of itself is a lot of nice protection, especially for the companionway area and the very forward ends of the cockpit. However, it’s not quite the right size, shape, or position to put the solar panels, nor does it provide any shelter overhead from rain for those sitting in the cockpit proper. For this we need to extend a covering back aft to a strong support where the panels will also attach. The most useful structure for doing this efficiently is to simply put an arch across the cockpit wherever we want it, and to span the space between the arch and the dodger with a waterproof canvas. In this case, the canvas makes good sense because it’s removable if we don’t want it, if it goes overboard in a heavy wave we don’t lose the protection afforded by the dodger, and it’s lightweight and easily replaced unlike the complex shapes of a canvas dodger and frame structure. The arch, on the other hand, must be quite solid.

I designed the arch to be able to do chin-ups on with regularity, although the height is not optimal since it must roughly match the dodger’s. I did not want the arch height to exceed the dodger height, even though that would be convenient for standing under. The main reason was that I wanted the solar panels to be relatively flat in case the sun was shining from aft, to at least pick up some power. Another reason was that it would create even more windage. A hard dodger is effectively permanent windage on a boat, and though I tried to make mine rather low and at least somewhat aerodynamic (haha) it will present some not-insignificant windage, especially in very strong winds. I did not want the arch to add significantly to this.

So the arch needed to match the dodger’s height and camber, and be quite strong. Initially I decided to go with a laminate of plywood (the Luan doorskins again as they bend easily to match curves, are generally a quality wood, and are inexpensive so I can template as I go). I set up the arch shapes for the crossbeam and, just for an extra measure of strength and hopefully some stiffness, I added some carbonfiber tape to the laminate as well. Here they are curing on the forms:



However, despite being much stiffer than ordinary plywood, they were still relatively too flexible for what I was looking for. And in this moment I learned a very important lesson: strength does not equal stiffness.

For a particular structure to be strong it simply needs to be built of materials with high tensile and shear strength. A few layers of kevlar, carbon fiber, or even multiple layers of fiberglass can all accomplish this. However, this often creates a very strong structure that is rather flexible at the same time - much like a willow tree is very strong but also flexible. After some research and consultation, again mostly with Bob, I found a solution. To add the stiffness easily, without adding significant weight or expense in exotic materials, I resorted to a construction called the “torsion box”. In fact, the torsion box form of construction is so stiff that I didn’t need any exotic fibers at all, and so with the exception of re-using the laminate I’d already made with the carbon fiber in it, I made the entire structure out of simple wood, epoxy, and fiberglass as I did with the dodger.

The first step was to re-laminate the arch crosspiece to match the dodger curve. This time, I did it directly on the dodger, screwing the wood pieces together to clamp the epoxy in place. I added an extra block to increase the curve, knowing that to some small degree the entire piece would spring back a bit when I released it. I wanted the natural curve of the piece to be that of the dodger, so this extra block compensates for that springback.



To add the stiffness via the torsion box, I added some 1/2” rips of 1” dimensional cypress wood to the edges of both sides of the laminate. In the photo, the top side is getting these pieces.

The wood strips were then topped with another sheet of plywood, forming a hollow beam with the two layers of plywood as the surfaces and the wood strips as the sides.



I constructed the side pieces of the arch the same way, but was able to glue them up as a complete unit in one go since there was no complicated curve to worry about.



The box structure is clearly visible here.



It makes a very nice wood pattern on the sides too.



The arch crosspiece getting the final surface installed. The epoxy bottles help ensure that the extra pieces conform to the curve already in the previous laminates, rather than trying to pull those laminates straight.



The finished crosspiece is a very nice piece of work. I got a lot of compliments on the dock for this one.



The arch with sidepieces installed, getting a test fit in the cockpit. The dodger is flipped up behind it for a layer of filler before final sanding and painting.



Getting the angles right… note the laminated bases for the arch to adjust the final height, and the temporarily-screwed-in-place side pieces to ensure the feet of the arch stay in position until the epoxy cures. These were super helpful additions to help “flow” the arch structure into the boat and hold it in place during initial curing.



Using some cheap conduit to help align the arch and dodger, and to layout the solar panel mount spacing.

The arch got a full coat of fiberglass, with extra reinforcements in the corners and at the base. I was able to do a chin-up without the arch moving much if at all. It definitely feels rock solid and like a part of the boat!

In part 3 I’ll cover finishing the arch and dodger and installing the solar panels.


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March blew by in a hurry, and April seems to be going the same way. There’s a LOT to catch up on here on the blog, but I’m still short on time to really convey the progress. I hope to write better single-topic articles on some of these endeavours before too long, but don’t hold your breath. As is the norm for now, here are some photos with brief captions.

In early March, the masts went in and a variety of preparation projects took place, including mast wiring, some electric motor troubleshooting, and the like. More interestingly, the yards and booms were crafted from Douglas-fir, but that was really just a simple matter of taking appropriately thick lumber, cutting it with a circular saw, sanding, routing, and painting. Nothing particularly fascinating or challenging there. The REAL items of interest came the weeks following. Today’s post is about one of them.

First, the sheeting arrangement for the mainsail required access for the sheets from the aft end of the cockpit. No big deal, as the mizzen already sheeted from there and the Junk rig’s loads are not radically worse. I just needed to strengthen the sheeting point and be done with it… except there was the issue of the solar panel arch, which was right in the way of the sheets and could not be accommodated in the new rig.


The arch in question can be seen above the cockpit in this image… if you look hard enough.

So the solar panels needed a new home, and I took advantage of this disruption to begin constructing something I’ve wanted for quite some time - a hard dodger. For those of you who aren’t familiar with what a “dodger” is… it’s sort of like a “windshield” for the cockpit - in the photo above you can see how effectively exposed the cockpit of the boat is, and since it’s the point of control for the sails, rudder, and other important aspects of the ship, the crew needs to be there regardless of the weather. Having a bit of protection from the wind, spray, and even the occasional overly friendly large wave is no bad thing, and can help keep the crew safe, warm(er), dry(er), and generally in better spirits.

The vast majority of sailboats out there, if they have a dodger at all, have a cloth one stretched over some relatively lightweight frames made often of stainless or aluminum tubing. This, in my opinion, is both a pain in the ass to make and easily destroyed if a person falls on it, the sun shines on it too long, or even a reasonable, moderate wave comes aboard with some intent. Any dodger, hard, soft, or otherwise, can in theory be carried away by the wrong sort of wave entirely, but the type of dodger I had in mind would be vastly less easy to coerce off the deck.

Now, a lot of people have talked about hard dodgers on sailboats before, but often what they mean is a dodger with a hard top that they can get up on, but retaining the cloth “windshield” portion. Again, not something I’m interested in.

I consulted with the eminently sensible and general expert in getting-things-done-right-for-cheap Bob over at Boat Bits (I’ve mentioned him before on this site a few times - he really is a sharp chap and thinks waaaaay outside the box as a matter of habit). His idea was clever: just build the dodger with plywood, using the “stitch and glue” method I’d just built my dinghy with. Then cover the whole works with fiberglass inside and out, and hey presto! you have a dodger which will stand up to most any abuse, look great while doing it, and be easy to build.

Now, I know that Bob can turn one of these out in about a week flat, and to be fair, I was able to do that for the basic frame and glasswork as well. But my finishing has really taken some time (not to mention I’ve been distracted by some other side projects which I’ll get to talking about shortly) so it’s not fully complete. That said, here are the photos of the templating, layout, and initial build.



I lay out the template using Luan doorskin plywood, 3-layer at about 1/4” thick. The heights will be adjusted later, here I’m trying some various angles and combinations to see what looks good.



Another view of the templating process.



Capping the final template with a roof piece, prior to trimming. I set the camber of the roof piece using a laminated curve of the same doorskin plywood, glueing two pieces back-to-back for stiffness, and then stitching that using aluminum electric fence wire to the roof piece. I tried two different camber heights before I got the look and companionway clearance I needed.



Another view of the template as I did some last minute fiddling.



I added some extensions to the sides and top to help keep a bit more spray off an occupant huddled behind it as the boat heels over a bit.



Here you can see the height of the dodger versus the old height of the arch, which is shortly to be removed.



The inside of the dodger after the fillets and glass layers cured.



The dodger gets a heavy coat of fiberglass and fillets inside and out, to encapsulate the template as a core. Now the dodger is a very strong, rigid structure with its own 3-D integrity and durability. It weighs about 35-40 lbs with the glass, wood, and all the epoxy on it. Not bad for something that started as two sheets of plywood!

In the next installment on this subject I’ll cover the companion piece to the dodger, the cockpit arch.

Stay tuned!


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Not much to say other than “FINALLY!”