Cleats of Douglas fir epoxied into place |
You'll recall that by the end of Part II of this article, I had constructed and dry-fitted all the necessary components for the shelf-and-partition system. In case you need a reminder, this picture shows the aft-locker as seen from within the V-berth. In other words, you're facing aft, toward the head and the main salon. The holding tank is situated against the bulkhead that separates the V-berth from the enclosed head and the hanging locker.
Yes, this is what it looked like when everything was dry-fitted, but before I could install any of those shelves and partitions in place, I needed to install the cleats of Douglas fir that would support the shelves. I also needed to do something with the two existing holes that were in this space.
Let's look first at the holes. The most troublesome hole for me was the one that used to house the old knotmeter. It was located directly beneath the holding tank that I planned to install (therefore, in the picture below, the hole is completely obscured by the tank).
With the tank out of the way, it's easy to see the hole in the below photograph. Obviously, I had to deal with this hole before I could do anything else. In case you're wondering, the black plastic served as a conduit for the old knotmeter and transducer cables. I planned to keep this in place for use with the new transducer cable.
As I said, there were two holes with which I had to contend. The first was the old knotmeter hole (the one seen above). The second was the old transducer hole (the one seen below). My plan was to fill the old knotmeter hole and enlarge the old transducer hole, as the new transducer and GPS would render the old paddlewheel knotmeter obsolete.
Before I could do anything with these holes, I needed to address a few problems in this part of the boat. First, I needed to enlarge the drainage holes in the bulkhead that separated the mid-locker from the aft-locker of the V-berth. All water from the chain locker would drain downward through the fore-locker, mid-locker, and aft-locker on its way to the bilge. I wanted to make sure that none of it would be impeded along its path to the lowest part of the boat, and the one existing hole in the bulkhead was inadequate. I also needed to remove the lightning grounding wire that was original to the boat. It ran from the forestay chainplate bolts in the anchor locker to the grounding bolt in the bilge. I had determined that this wire was inadequate by modern standards and was thus obsolete. I address this issue more fully in my article on my grounding system for the Ericson 25. The old grounding wire is the blue one in the picture below. The yellow wire is for the fluorescent work light that I was using for this project.
Below you can see the two new holes that I drilled in the bulkhead for drainage purposes. You can also see that I have cut the blue grounding wire.
As I said in the first part of this four-part article, the transducer that I planned to put into this hole was the Airmar B60-12. This bronze transducer was slightly larger in diameter than the old plastic transducer. Therefore, I had no choice but to enlarge the existing hole.
How, you might ask, does one go about enlarging an existing hole in the hull? I suppose there are more ways than one, but here's how I did it. First, I used a 2-1/8 inch hole saw to cut a plug of sorts out of a scrap piece of southern yellow pine.
I selected 4/4 inch pine (in other words true 1 inch thick pine), because I figured it would make things easier for me in terms of the friction it would provide within the hole.
The 2-1/8 inch plug proved to be far too small for the hole, even though the measurements I took in advance seemed to indicate that the hole was this size.
I decided to step it up to 2-3/8 for the next plug.This hole provided just enough room for the new transducer, so at least I knew exactly what size hole-saw I needed for this installation.
As it turned out, the internal diameter of the 2-3/8 inch hole saw provided just the right sized plug for the old hole in the hull.
After I hammered it into place with a dead-blow hammer, I was ready to roll. Before I drilled the hole, however, I thought it would be a good idea to go ahead and tackle a more challenging task - grinding out a beveled circle around the old knotmeter hole as preparatory work for the filling of the hole with epoxy and cloth.Here was the equipment I assembled for this grinding job. As always, I also wore a long-sleeve shirt and long pants. I figured the more of this bottom paint and fiberglass I kept off of me the better.
As per the suggestions of various experts on the subject, I decided to bevel the hole at a 12-1 ratio with regard to the thickness of the hull. Since the hull of the Ericson 25 in this area is 1/2 inch thick, I scribed a circle to a diameter of about 6 inches.
The bottom paint was quite thick with what appeared to be many years worth of applications.
One of the challenges I faced when grinding around the scribed circle was avoiding the centerline of the boat. It is difficult to tell in this picture, but the hull is V-shaped in this area.
It's also difficult to tell in the above pictures and in the picture below that between the white gel-coat and the red bottom paint there was a layer of gray. Perhaps this was some barrier coat that was applied long ago as a protective measure against possible blistering from water intrusion.
In the photo below you can see at the top of the circle I have ground down through the barrier coat and the gel-coat all the way to the fiberglass hull. In the bottom right of the circle the gray barrier coat is fully visible.
The picture below gives you some idea of just how thick that bottom paint really was.
After I had removed all of the gel-coat in this area, I discovered a blemish of some sort. Maybe at some point this had been a blister, and maybe this had been the reason why a barrier coat had been applied to the hull (if indeed the gray layer that I discovered was indeed a barrier coat).I didn't think that the six-inch diameter circle provided sufficient room to create a good, consistent bevel, so I decided to increase the diameter to seven inches. I also figured this would allow me to more fully inspect the blemish that I had discovered.
The blemish was not full of water, but it was an anomaly nonetheless.
Below you can see that I've begun to create the bevel at around the 10 o'clock position.
Now, as you see below, the bevel fully encircles the hole, and the blemish has almost disappeared.
By this point, I've expanded and cleaned up the bevel a bit.Now, as you see in the picture below, I've made my way down through several layers of fiberglass cloth and mat.
Deeper the bevel goes.
And deeper . . .
After I had finished beveling the hole with the grinder, I decided it was time to break out the epoxy in preparation for laying up the cloth that would fill the hole. I discovered that in the months since I had last used my MAS brand resin, it had crystallized and turned hard. It had done this in the past. To remedy the situation, as I had in the past, I simply placed the resin container in a black plastic trash bag and set it in the sun. After a few hours, it was fully liquefied once again.
Meanwhile, I got to work inside the boat. I knew I needed to grind away the paint and get down to the fiberglass so that the epoxy and cloth that I would apply to this side of the hole would bond with the hull.
I began by scribing a circle that was seven inches in diameter so I would know the limits of the grinding work I had completed on the exterior.
I then drew a square around the circle to give myself a guide for grinding away enough paint and fiberglass for the cloth that I would place in this area.
Before I broke out the grinder, I wiped down the entire area with toluene in order to remove any wax or oils that might prevent the epoxy from bonding with the hull.
Having removed the bottom paint from the hull and having removed the gray paint from the interior of the V-berth locker, I could now see the circumference of the ground-out portion of the hull very well.
I continued grinding until I had removed almost all the gray paint.
With the work light turned off, it was very easy to see the hole.
After I had finished grinding this area, I decided it would be a good idea to see how the Douglas fir cleats for the holding tank shelf might encroach upon this hole-filling job. I realized at this point that it would be necessary to combine the hole-filling job with the cleat-installation job, since they were in such close proximity to one other.
Likewise, I realized that my grinding work was not yet finished, as I would need to account for the cloth that I planned to lay up against the hull in order to secure the shelf.
I used a black Sharpie marker to indicate to myself the area in which I planned to lay the cloth.
I also decided it would be a good idea to go ahead and figure out where I needed to do additional grinding for the other set of cleats and also the tank-standoff battens that I planned to bond to the bulkhead with epoxy.
You'll recall that the holding tank and the components of the aft-locker storage system looked this way during the dry fit that I had already performed.
I had to make sure that the cleats that supported the center storage shelf were situated just right.
Otherwise, the shelf would not sit correctly on the cleats. This error would then lead to other errors.
I also wanted to make sure that there would be a little bit of space between these cleats and the components of the holding tank shelf system. This space would allow water to flow freely to the bilge.
Satisfied with the placement of the cleats, I marked the hull with a black Sharpie and removed the cleats to reveal the lines.
I also marked the spots where the tank-standoff battens would be located on the bulkhead.
Here's the way the whole thing looked before I started doing the additional grinding.
I started by grinding the area where the holding tank shelf would be bonded to the hull.
Incredible amounts of dust were generated by this grinding. This gray paint was tough.
Here you can see the area that I cleaned up with the shop-vac just prior to grinding.
Now it was time to focus on the area where the storage shelf cleats would be located.
There it is.
During the grinding process, I, of course, had obliterated the black reference lines that I had made with the Sharpie marker. Knowing that I would do this, I had planned ahead and had made reference marks on the bulkheads,so that it would be easier to redraw the lines at the end of the grinding process.
The grinding for the tank stand-off battens.
The reference lines for the cleats. All that I needed to do now was to get going with the epoxy.First, I cut the cloth for the beveled hole on the exterior of the hull. I used scraps of 10 oz cloth that I had saved for miscellaneous purposes.
As you see, I cut five total pieces, each one slightly smaller than the next.
My plan was the apply the largest piece first, as per the suggestion of Don Casey, This Old Boat, 2nd Edition. The idea is that the largest piece will offer the most surface area for the initial bond.
After doing the dry lay-up of the cloth, I began getting a little concerned about not being able to fair out this job after I had laid-up all of the cloth. Therefore, I decided it would be good to grind off a little more of the bottom paint.
To the right you can see the other side of the hull, opposite the centerline. In case you're wondering, the stuff in the hole consists of wadded-up paper. I had already vacuumed the interior, and I did not want any of this dust entering that area.One last thing I needed to do before applying the cloth and epoxy was to drill out the existing hole to make it slightly larger. You'll recall I needed to do this for the new transducer.
Cutting a nice, clean hole was really quite easy.
Although it looks like the cleat on the starboard side encroaches on the glow emitted by the beveled hole on the exterior of the hull. It does not. It is just on the edge. Consequently, it sits on 1/2 inch of fiberglass - the full thickness of the hull in this area of the boat.
I began by cutting four strips of fiberglass tape, one for each side of the cleats. My plan was to glue and fillet the cleats with epoxy, all at one time. I would then lay the tape over the fillets and wet out the tape with epoxy thickened with colloidal silica.
I also cut out two pieces of 9 oz. biaxial cloth. I planned to lay these in the area between the cleats. My thinking was that this would reinforce the patch job that I was about to do on the exterior of the hole. I wanted the cloth and epoxy on the interior to bond molecularly with the cloth and epoxy on the exterior. For this reason I had planned in advance to do all of this epoxy work within the same time-frame.
I laid out all the cloth in the cockpit in preparation for the several trips I would have to make from the cockpit to the V-berth.I used MAS F.L.A.G. (Filleting, Laminating, and Gluing) Resin and Medium Hardener for the gluing and the filleting. I used RAKA 127 Low Viscosity Resin and 350 Non-Blush Hardener for the wetting out of the cloth.
In the two pictures below you see that I have glued the cleats into place, and I have provided them with generous fillets. I thickened the epoxy with colloidal silica to the consistency of peanut butter for this part of the job. Notice that I avoided putting epoxy in the area near the bulkhead. The cleats sit about 1/2 inch from the bulkhead. I did this to allow for the free flow of water
In the next two pictures you'll notice that I have added the fiberglass tape to each side of the cleats, and I have spread thickened epoxy throughout the middle area in preparation for laying down the first piece of biaxial cloth. The consistency of the epoxy-colloidal silica mix for this part of the job was of syrup or paste.
You can see in this picture below how lumpy the epoxy was when I finally declared this part of the job complete. The texture was rough, because I had applied a final coating of epoxy that had been thickened to the consistency of peanut butter. I used a chip brush to apply it. I considered using a squeegee to fair this area, but I was a little worried that the scraping action of the squeegee would cause the pieces of cloth to become misaligned. I figured that leaving it lumpy was a safer approach. I would just come back later and sand it, and, if necessary, fair it with epoxy thickened with colloidal silica.
A few weeks later, after being distracted by other projects, I returned to the V-berth and installed the next two cleats, using the same methods I had used for the first two. I also, at this time, applied more biaxial cloth and thickened epoxy over the old instrument hole. Note that I have spaced the large cleats to allow for water drainage. I did not plan for water to be flowing down the sides of the hull on a regular basis, but I thought that there would certainly be condensation, and I wanted to provide an escape route for this moisture to the bilge.
After the epoxy had cured, it was time for another dry-fit. Understandably, things had shifted a tad during the gluing and filleting process, and it turned out that the holding tank shelf was now just a little too wide to fit into place. Therefore, I took the shelf to the table saw and removed about 1/16 of an inch from the forward edge.
Next, I wanted to dry-fit the other components to see if I needed to make any other adjustments.
Fortunately, everything fit together well.
You can get a good sense from the picture below of just how much space is available for storage, if you have a partition such as this one.
The next thing I needed to do was to cut some braces from scrap wood - braces that would help to keep the holding tank stand-off battens firmly in place during the glue-up process. Although this cutting of the braces might seem to have been a simple job, it actually took many trips back and forth from the boat to the table saw, since each brace needed to be custom cut. There were irregularities in the bulkheads that made a one-size-fits-all approach impossible. This one picture illustrates how time-consuming so many of the seemingly easy tasks are in the refitting of an old sailboat.
My plan for gluing up the holding tank stand-off battens was to glue these up at the same time that I applied the epoxy and cloth to the top of each of the cleats. Why, you might ask, did I want to put cloth on top of the cleats rather than just leaving them bare? To my mind, this would serve two purposes. First, it would protect this rather soft wood - Douglas fir. Secondly, it would strengthen the entire set-up, since the cloth would overlap the other pieces of cloth that were supporting the fillets.
Before I could apply the cloth, I had to grind and sand the existing epoxy so that the new epoxy could form a mechanical bond.
Like all grinding and sanding projects, this one was no fun at all, especially since much of it had to be done by hand on account of the curves involved.
After hitting the entire locker with the shop-vac, I wiped the work area down with acetone to get rid of any residue that I might have missed.
Here we see the cleats after the wet-out of the cloth with epoxy.
After I wet-out the biaxial cloth, I thickened-up the epoxy with colloidal silica and filled in the rest of the weave.
I used this same thickened epoxy to glue the holding tank stand-off battens to the bulkhead.The battens wiggled a little as I applied one brace and then another, but after I had gotten all of the braces in place, I was able to tap the battens into their correct positions (as indicated by the black lines I had previously drawn on the bulkhead). There they stayed, and there they should always stay, glued as they are with epoxy and colloidal silica.
My final task for this stage of the project was to sand and fair the epoxy work I had done on the exterior of the hull for the purpose of filling the old knotmeter hole. For most of this job, I used my Dewalt angle grinder with a 36 grit disk. That was the only way I could make any significant headway against the epoxy and colloidal silica.
I had to take frequent breaks to give my arms some rest. During these breaks, I took the following pictures.
It became evident as the grinding and sanding progressed that I would need to fair this area. There were uneven spots that just couldn't be leveled out. These were not the result of careless use of the grinder. Rather, they were the result of uneven application of the final pasty layer of epoxy and colloidal silica. As I said earlier, I resisted the urge to pass the squeegee over the patch job for fear that I would cause the layers of cloth to shift from their proper position, directly under the center of the old hole.
Convinced that I should go no further with the grinding and sanding, I decided it was time to wipe down the whole area with acetone in preparation for the necessary fairing job that lay ahead.
All clean and ready to go. In case you're wondering what the black specks are amidst the colloidal silica, it was a windy day when I was doing the patch job, and in the middle of my application of the epoxy and silica a gust of wind caused some leaf debris that was under the boat to enter my epoxy pot. Given the time-sensitive nature of this lay-up, I decided to press forward.For the fairing job, I mixed up a small amount of epoxy and thickened it with colloidal silica. With the pot in one hand (and the accompanying chip brush), and with the yellow squeegee in the other, I climbed underneath the boat.
Having applying the epoxy with the chip brush, I skimmed the whole area with the squeegee. After several passes, the area was as fair as it possibly could be, given the size of the squeegee. Ideally, I would have had a squeegee that was just as wide as the circle, so that I could make but a single pass.
It took a while, but the epoxy eventually began to yield.
When it looked like I was close to the end, I grabbed some acetone to clean up the area and get a good look at what might remain in terms of sanding.
I found a few minor divots here and there, and after I had hit these with a hand-held piece of sandpaper, I wiped the whole area down again with acetone and declared this part of the project complete.
I'd say this patch job of the old knotmeter hole turned out pretty good. Having described my work on the holes and cleats, this concludes the third part of my four-part article on how I constructed a holding tank shelf, a storage shelf, and storage partitions in the aft locker of the V-berth of my Ericson 25. Part IV will concern the installation of the holding tank shelf and the painting of the components and the locker itself.
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