Replacing the Head Vent

We decided to change the head vent. As everyone who’s spent time aboard knows, this is a very important vent. It’s even more important than usual to us, since our composting head needs to vent continuously through it to work properly. Some Albergers on Chesapeake may remember the time the fan in that head quit working, and our desperate quest to replace it...

Why change it? The vent we had leaked gently at times, into both our head compartment and our head. It wasn’t easily accessible with the setup we had, nor could we close it when the weather turned nasty. And a close look suggested that the leaks might be because the dorade box the vent was sitting on wasn’t all that effective - so we decided that we would change to a closable vent without a dorade.

We had already changed the original cowl vent, and had a round vent (plastic, and unhappily destroyed when a heavy object hit it) sitting on our rectangular dorade box. So our first step was to remove the vent - and then the dorade box. We had already decided on a vent with a stainless steel cover that promised to move a lot of air, so the next part of our work was based on that purchase.

The vent would work best if it was sitting level (as level as anything ever sits on a sailboat), so creating a level surface for the vent to sit on was the next part of the project. Once we had cut the dorade off we were left with a hole around which to build the new base, and an area around it that needed to be repaired.

Since we had decided a round base would look nice and work well, Richard started by cutting circles of fiberglass mat. There were two considerations when cutting the mat:

* The base would be larger at the bottom than the top, and
* We had to build up one side (the out side) more than the other (the in side), due to the curve of the cabin roof.


- First, the size of the top circle was matched to the base of the vent we were installing.
- Then the bottom circles were cut larger than those for the top. To allow for the slope of the roof he cut progressively more off one side of the circle as he cut the lower circles. In other words, the bottom circle had the largest area removed and the longest straight line to be laid along the cabin, and the top circles were complete circles.

Since there was already an existing vent hole, Richard cut matching holes in the center of the circle for each piece of mat, and used the center hole to help center the layers of mat and resin as he worked. He also used the inside of the old vent to keep the hole open and even while he was working. Inside the head compartment he put tape over the hole to prevent resin dripping through.




Then he laid the circles up in a number of layers, centering them by matching the holes in the pieces of mat to the original vent hole. Each layer consisted of eight circular pieces and was laid up like this:

* First, polyester resin was rolled out on the surface to be covered.
* Then a layer of mat was put in place.
* The layer was saturated with resin, and the resin rolled out (pressed down into the mat) with a cheap 3 inch roller.
* Another 7 pieces of mat were put on the same way.
* After the eighth layer of mat, Richard used a steel roller on top to get rid of any air that might have been trapped during the lay up.




(When using the rollers, it’s important to press hard enough to get rid of any trapped air - you can see the air bubbles moving - but not so hard that the layers of mat move. This takes some practice.)

Eight pieces of mat create about a 1/4 in thick layer; Richard laid up 8 or 9 layers altogether, allowing each layer to cure before putting the next one on.

The first part of the process left us with a shape which was roughly the one we wanted. Refining the completed shape began when Richard put on the last layer of mat and resin. He mixed up ‘gunk’ (resin thickened with silica and talc) when he was preparing the resin for the last lay up, and spread the gunk on top of that layup to make a smooth, level top. On top of the gunk he put a piece of waxed plexiglass we happened to have, weighed down with a handy bit of former outboard bracket, and this left the hardened top surface nice and flat and smooth when we removed it.




( A note: we often work with things we happen to have at the time. You should know that waxed MDF board would have worked much better on the top of the vent base than plexi.)

Once everything had set, Richard mixed up and used more gunk to smooth off the sides of our new base. He applied the gunk with a flexible plastic spreader; by the time he was finished we had the basic shape.

After that I took over. I did a lot of sanding, to make the shape as smooth and symmetrical as I could. Then Richard gelcoated the whole base, and I went back to sanding - this coat of gelcoat helped me to see imperfections I would have missed otherwise and filled in some small areas. Another coat of gelcoat, brushed on thickly, was followed by more sanding. Then Richard used polyfair to fill in the remaining irregularities, and I sanded yet again.




Once the vent base was just about ready Richard used a rotozip to open up the hole in the middle to the size we needed for the new vent, and then cut away the thin layer of resin that had accumulated on top of the tape inside. With the hole was the right size and everything looked ready, another coat of gelcoat was applied, using a roller and covering the whole area that we had been working on. He also brushed gelcoat on the inside of the vent hole- that will be sanded when we start work on the inside of the head compartment.




A little sanding made the surface a little more even, and there will be more sanding before we put paint on the cabin and non-skid on the areas that need it, but for now we had gone far enough. So then we put the vent on!

The New Anchor Locker

By the time we came into Halifax last summer we knew that we would need to do something about our anchor stowage. When we set off on our adventures we had already had to rethink our original plan, which involved making slings of plastic mesh forward of the bulkhead separating the vee-berth from the bow. The mesh was not strong enough, so instead we devised two canvas slings to hold our anchor chains. They proved quite workable - the anchor chains did not rattle against anything except themselves, did not tangle and and were kept separated from each other. Overall, we had very little problem with them.

However, we knew that they would be a temporary solution. When we looked at them last fall the canvas was moldy and beginning to weaken. It was time to come up with a new and hopefully better solution.

When we were deciding what to do we had two considerations - to keep the anchor chains separated and safe, and to keep them - and their weight - low in the boat. With these thoughts in mind, Richard devised the anchor locker that now sits just under where the windlass will be installed.

This time the anchor locker is made of fibreglass, and sits low down in the bow, just in front of the bulkhead separating cabin from bow space. It is divided in two along the line of the bow, so that each chain will sit on one side of the barrier and against the hull.

To make it, Richard drew up a set of cardboard pattern pieces, first for the piece to go in the middle, then for a small piece to go toward the bow, then for the pieces that go from the bulkhead down to the hull, the rear wall of the compartment.

Then he made fibreglass panels, 1/4” thick ( 6 mm). He laid them up on a flat, waxed surface with the pattern pieces drawn on it, using mat and polyester resin, making them close to the size and shape of the pattern pieces, but a little larger. Then he used the pattern pieces to cut the finished pieces out, using a diamond cut blade on an angle grinder (he has become very proficient in the many uses of a grinder).

He put the middle piece of the locker in first (the one along the line of the bow), and fastened it in place with strips of fibreglass mat wet out with polyester resin.




Then he put the front piece in the same way.




Then the two pieces at the back.




Along the hull, up to the height of the middle divider, Richard added foam core plus a fibreglass matte layup, to deaden the sound somewhat and strengthen the hull where the chains may move around.



There are holes to allow the water to drain from the chains into the bilge, right in the middle of the boat, and holes at the front of the locker in case moisture needs to drain from there - also in the middle.

Once the whole anchor locker had been assembled, Richard rough sanded the whole thing to remove any sharp edges, and then finished it with brush gel coat (thicker than the spray) using two coats, sanded in between.




And there it is - our new anchor locker!

If you have any questions about what we did, or any comments, please click that comment button below and let us hear from you.