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| The aft panel, dry-fitted into place |
The installation of cleats and panels in a fiberglass boat typically entails some degree of epoxy work. Wooden cleats must be joined to something, and more often than not they must be joined to the fiberglass hull or to some other fiberglass structure within the boat. This joinery work itself entails some degree of sanding and grinding, which in turn entails a thoroughly unpleasant work environment. It's the price that often must be paid when you modify your fiberglass boat. Whether this unpleasant labor is worth the price all depends, I suppose, on whether or not your modifications are both functional and aesthetically pleasing. In this, the fourth of twelve postings on the modifications I made to the galley sink cabinet of
Oystercatcher, my Ericson 25, I describe the epoxy work involved in the installation of the cleats and panels that I had earlier constructed for this space. At the time, this work, I must confess, often did not seem to be worth the price. In the end, though, when the functional and aesthetic qualities of this project became more evident, this labor was certainly worth the price.
Let's begin by looking at the forward cleat. This large cleat would support the large shelf on its forward side. After drilling the four screw holes, I countersunk each hole so that the head of each screw would not protrude from the surface.
I then dry-fitted the cleat and tested for level.
Once I was satisfied with the position of the cleat, I drilled the remaining holes. The large hole in the bulkhead beneath the cleat originally housed a plastic conduit through which the VHF coaxial cable had run. I would later fill this hole and reroute the conduit near the bottom corner of the bulkhead. This original conduit had been another reason why the original cabinet space was unusable.
With my Rockwell Sonicrafter oscillating tool, I sanded the area behind the cleat in preparation for bonding the cleat to the bulkhead with epoxy.
I also used my angle grinder to remove that stubborn gray paint.
Next, I cleaned the surface of the freshly ground fiberglass with toluene. This solvent is a rough-neck cousin of acetone, and as such is more aggressive in its removal of dirt, wax, and other debris.
I then mixed up some epoxy, wet out the work area, and glued the cleat into place with thickened epoxy. The thickening agent? Colloidal silica.
After I had glued and screwed the cleat into place, I used the left-over thickened epoxy to make a fillet underneath the cleat. Normally, a fillet is used to strengthen a cleat. In this case, the fillet served to seal the cracks here and there between the wood and the bulkhead.
With this one cleat in place, I could now more easily dry-fit the main shelf and determine exactly where I needed to cut the hole that would allow access for the hose from the galley sink. Notice that I am cutting this hole with a hole saw and that I am approaching the shelf from an angle.
This angled cut was necessary on account of the orientation of the seacock beneath the shelf.
Without the angled cut, the hose would not pass smoothly through the hole.
With these jobs out of the way, I could now focus on the panels.
Let's begin with a look at how I installed the forward panel. This was the smaller of the two panels, the one that would seal off the galley cabinet from the space behind the backrest of the main salon settee. In preparation for the installation I cut two pieces of 6 ounce fiberglass tape. One piece of tape was 4 inches in width, the other 6 inches. I had ordered these rolls of tape from RAKA in Ft. Pierce, Florida. "Tape" is the term commonly used for thin strips of fiberglass. There are, of course, no self-adhesive qualities to this tape.
To de-wax and clean the fiberglass hull, I used toluene, a high-strength organic solvent that is, as I said, a rough-neck cousin of acetone.
After I had de-waxed the hull, I installed a wire cup-brush in my Makita electric drill.
I used this brush to scuff the surface of the fiberglass. This would provide for the epoxy a surface more conducive to bonding.
The surface of the fiberglass as it appeared after its scuffing.
Again I applied toluene to the work area to clean up the dust and other debris in preparation for the application of epoxy.
For this job, as on so many others on this boat, I used RAKA 127 Low Viscosity Resin and 350 Non-Blush Hardener. To thicken the epoxy-resin mix I used colloidal silica.
I began by wetting the work area and the piece of plywood with neat epoxy. I then thickened the epoxy with colloidal silica to the consistency of peanut butter. This thickened epoxy I applied to the plywood. Then I clamped it into position.
The next day, after the epoxy had fully set, I removed the clamps. Then I wet out the work area on the hull and the edge of the plywood, and I applied the two layers of fiberglass tape, the small piece topped by the large piece. I should note that I had cut the plywood small enough to allow for a half inch gap between the edge of the plywood and the hull. I did not want the hard edge of the plywood to come into contact with the somewhat flexible hull.
With the forward panel installed, it was now time for me to focus on the aft panel. The glue-up of this panel would require multiple scraps of wood to serve as clamps, since there was no other way to hold the panel in place. During the dry-fitting, which you see pictured below, I made many trips back and forth to the table saw to get the length of these pieces of scrap wood just right.
I had to custom cut these pieces of wood to different sizes, since the dimensions of the cabinet space varied. I numbered the pieces, so I would remember where to place them when the time came for the glue-up.
In the pictures that follow, you'll be treated to a flashback of sorts. You might have noticed in the pictures of the forward panel installation that the hull area adjacent to that forward-panel work area had already been hit with the grinder. I had in fact ground the hull in the work area for the aft panel prior to grinding the work area for the forward panel. I did, though,
install the forward panel first. This was why I discussed this area first.
Now that I've cleared this up, let's focus on the grinding necessary for the aft panel installation. Since this work area was somewhat open, it was not necessary for me to use the wire cup brush on the power drill. Instead, I could use the angle grinder. This tool, especially with a 36 grit disc in place, can remove a lot of material quickly. For this reason, you must be especially vigilant not to remove too much material. Notice the two different colors in the work area below. The top color is gray, the bottom, brown. The paint color used by Ericson in this space (and in other storage areas on the boat) was gray. I started grinding in the lower area, since this was the easier area in which to work. I lightly ground the surface until I had removed most of the gray paint. I started at the bottom and slowly worked my way up. When I came to the point that you now see distinguished by the gray color, I was puzzled to discover that the gray paint did not seem to disappear the same way it did in the lower area. After a little bit more grinding, I paused to inspect the work area more closely. Much to my dismay, I realized that I had ground a small divot into the hull in my effort to remove the gray paint from this transition point. Yes, I had removed the gray paint, but I had also began to grind down into the fiberglass structure of the hull itself. I immediately stopped working in this small area, and I began to grind lightly in the area above it. Eventually it came to look exactly the way it looks in this picture. It was during this additional grinding that I realized that the reason why this area of the hull was gray (and not just painted gray), was that Ericson had laid up this area of the hull differently than the lower area. The lower area was thicker and was brown in color. The upper area was thinner and gray in color. My mistake occurred at the transition point.
In the picture below you can see exactly what I'm talking about.
This divot was not dangerously thin. It wasn't as if I could make it flex by pushing it with my fingers.
Nevertheless, it did cause me some concern. The right thing to do would be to reinforce the area with some biaxial cloth. That was what I started thinking.
To carry out this reinforcement job, I began by cleaning the area with toluene.
I then cut three patches of varying sizes out of 9 ounce biaxial cloth that I had purchased from RAKA, Inc.
I wet out the hull and then applied the three patches, laying up the smallest patch first. After I had laid up all three patches, I covered the whole area with another piece of biax. This made four total layers.
I took a break and then came back and laid up two more large pieces for a total of 6 layers of biaxial cloth. This patch job probably made this area of the hull stronger than it had been originally.
With this repair work out of the way, I could now focus on the installation of the aft panel. I began by cutting a strip of XPS foam. This strip of foam would be used as a cushion of sorts between the hard edge of the plywood and the hull.
XPS foam is easily obtained from home improvement stores like Lowe's or Home Depot. If you are interested in reading more about the compatibility of different foams with epoxy see my article, "Lazarette Modifications, Part 4: Tabbing for the Bulkhead."
With the panel in place and the strip of XPS foam in hand, I started to work the foam into the space between the panel and the hull. I was upset to discover that the space, of course, was now smaller than it had originally been. The 6 layers of biaxial cloth were the cause. At this point, I had no choice but the remove the panel and use the jig saw to cut off about one eighth of an inch worth of wood from the curved edge of the panel. Did this mean that I had to apply two coats of epoxy to this new edge? Did this mean that I had to wait a day or two for the epoxy to cure before I could sand it? Yes and yes.
With the newly cut board in hand, I was able to work the XPS foam into a nice and snug position. What I was creating here was essentially an additional bulkhead for the boat. This would, therefore, provide additional strength to the hull.
Now that I knew these components would fit, it was time to clean up this area in preparation for the application of epoxy. I had already wiped down the fiberglass on the side of icebox with toluene and I had already sanded it and re-wiped it with toluene. Now it was time to consider other areas that might be difficult to access once this panel had been glued into place with epoxy. First, there were the areas around the sink. These were covered with loose pieces of fiberglass.
There was also the area where I had applied the biaxial cloth. This area I sanded with the Rockwell Sonicrafter oscillating tool, since it was easier to use this tool in this space than a regular quarter-sheet sander.
There was also some dried epoxy that I needed to remove from the exterior of the cabinet. This stuff had squeezed through the holes when I had glued the forward panel into position. Normally, I would have cleaned the excess up immediately, before it had time to cure. I had not seen this stuff on account of the clamps that had been in this area.
The Dremel, with a sanding drum attached, made quick work of these epoxy drips. I wasn't very worried about the damage to the gelcoat. This area, after all, would soon be covered by the panel.
After everything was well sanded, I wiped down the relevant areas with toluene.
The area around the sink was especially stubborn and hard-to-reach.
I decided that the best way to get rid of those loose piece of fiberglass was to hit this area with some 40 grit sandpaper.
This helped, as did the Dremel with the sanding drum.
This is the sort of stuff you definitely don't want in your stack of soup bowls, right?
I also took the time to clean the area behind the ice box. This area was almost inaccessible. It would be especially inaccessible after I had installed the panel.
Here's what it looked like. Full of dust from all the sanding. Note the strip of XPS foam in the background. That is from my project in the lazarette.
While I was doing this, I gave the panel yet another coat of epoxy, this time along its square edges.
Not having a great deal of success with the Shop-Vac, I decided to wipe down the area behind the icebox with acetone.
This helped.
The dirty rag says it all.
These attachments on the Shop-Vac were also useful, to some degree.
At last this area seemed reasonably free of sanding dust.
One final wipe with toluene. Did I wear a respirator every time I used this stuff? Absolutely.
I also used gloves. Every time. No exceptions.
Second coat of epoxy along the square edges.
Sanding the square edges.
One final dry-fit.
For the installation, I began by gluing the XPS foam into place with epoxy. I allowed this to sit in place for a day or two before removing the braces.
When I did remove the braces, I was pleased to see that the XPS foam was firmly in place.
In terms of the glue-up of the panel, I do not have many pictures. The temperature was in the lower 90s Fahrenheit when I did this job. Therefore, I did not have a lot of open time on this epoxy work. I began by wetting down the entire surface of the panel with neat epoxy. Then I wet down the side of the ice box. Afterwards, I mixed up another pot of epoxy and thickened it with colloidal silica. Using a notched plastic trowel, I spread the epoxy in swirls, evenly across the surface of the panel.
I then pushed the panel into position and applied a few of the wooden braces. I did not want to apply all of them just yet, because I still needed to apply the fiberglass tape that would bond the edge of the plywood to the hull.
Below you can see all of the wooden braces in place. Likewise, you can see that I have now applied the fiberglass tape.
It's a little bit easier to see the fiberglass tape from this angle. You can also see (at the bottom) that I have applied two different layers of tape. Just as was the case when I taped the small forward panel, I applied the 4 inch tape first and then the 6 inch tape.
I placed an old bed sheet underneath the panel to prevent any excess epoxy from dripping down and accumulating on the hull. Notice the white bed sheet (which you see to the right) that is nearby. There is a space beneath the icebox that extends from the sink cabinet to the lazarette. At this time I was also working on the lazarette, and I did not want any dust from that project to work its way into the area around the icebox that I had just cleaned. This corridor of sorts between the galley sink and the lazarette was yet another reason why I wanted this modified sink cabinet, which would be used for the storage of plates, bowls, and glasses, to be sealed off from its adjacent spaces. If it were not sealed off, then all odors and gasses from the lazarette would freely float upward into this cabinet. At the bottom of the lazarette was the bilge. Within the lazarette there would be batteries, which of course would emit gasses when being charged. Also within the lazarette would be bags of trash. None of the odors or gases from these things would be welcome in this cabinet.
Typical scene outside the boat during much of the refitting, after a full day's work. I would stand in the companionway and do my epoxy mixing on the cockpit sole. After I was finished, I would, while still standing in the companionway, toss all used epoxy pots, paper towels, and gloves overboard. The following day, after the epoxy had hardened, I would gather the gloves and paper towels and then throw them away. The plastic epoxy pots I would reuse as many times as possible.
A day or two later, after the epoxy had dried, I turned my attention to the aft panel cleat. This of course was the cleat that would support the large shelf on its aft edge. In the picture below, I am making sure that the cleat is as level as possible. I'm using just two small screws to support the cleat during this leveling process.
Amazingly, this shelf was level, both forward to aft and port to starboard. Oh, and by the way, the boat itself was level. I made sure of this by testing the trailer for level.
Before installing the cleat, I needed to do some sanding. It would be much easier to sand the tape on the hull and aft panel prior to the installation of the cleat rather than after the installation.
The Rockwell Sonicrafter oscillating tool again proved to be an essential tool for this project. With its small triangular sanding head, it could reach areas that were inaccessible to the larger quarter-sheet sander.
When the time came to drill the screw holes (through the existing holes in the cleats) into the aft panel, I turned to my Milwaukee Tools right angle attachment. Like the oscillating tool, this tool was essential, not only on this project but also on many others during this refitting.
Finding toluene unnecessary at this point, I wiped down the area behind the cleat with acetone prior to the application of epoxy.
The aft panel after I had wet it out with neat epoxy.
The cleat after it had been wet out.
The cleat, covered with thickened epoxy.
The cleat, installed. Note the countersunk screw holes filled with thickened epoxy.
Now that I had completed these tasks, I could focus on the construction of the small shelf and the partitions that would hold the plates, bowls, and cups. That is the subject of the fifth part of this multipart article.
This ends this posting on how I installed the panels and cleats for the new galley sink cabinet on
Oystercatcher, my Ericson 25.
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