Lazarette Modifications, Part 8: Gluing-Up the Port and Starboard Shelves

The starboard shelf, glued-up and glassed into place
Having pre-painted the various components it was now time for me to glue-up the port and starboard shelves in the lazarette of Oystercatcher, my Ericson 25. This part of the project would require some special tools and quite a bit of patience, as there were many steps and many days for the completion of this job.

I began by pre-drilling the mounting holes in the port side shelf.
I countersunk these holes, since I planned to use flathead wood screws for the installation.
The Milwaukee Tools right angle attachment, which I had recently purchased online, was invaluable for this procedure.
You'll recall from Part 7 of this article that this tool, at $50, was not cheap, but it was certainly worth it.
Likewise, the StubbyBit set that I purchased online at the same time was equally valuable.
Without the right angle attachment, I could not have drilled the pilot holes for this shelf.
After I had finished drilling the pilot holes, I inserted a Phillips head drive into the right angle attachment and temporarily installed the flathead screws.
The screws were flush with the top of the shelf, which is exactly the way I wanted them. This way, I could lay down some fiberglass cloth on the joint between the shelf and the bulkhead.
With this out of the way, I turned my attention to the starboard side.
All of this drilling that I was doing was, as I indicated above, pre-drilling.
I would have to remove these screws and the shelves themselves before mixing up the epoxy. Otherwise, I would not be able to glue the joints.
Having finished the pre-drilling of the holes, I began to cut the 10 ounce fiberglass cloth that I would lay on top of the joints.
The common term for small rolls of cloth I used is "tape," even though there is nothing about them, perhaps aside from their size, that resembles adhesive tape. The chief benefit of using tape on joints is that it saves you a lot of time cutting small, homemade pieces of tape from a larger piece of cloth.
Before dry-fitting the tape into place, I wiped down the work area with toluene to remove sanding residue and any residual wax residue that might remain on the hull from the original lay-up at the time of manufacture in 1975.
Each joint got two layers of 10 ounce tape. One of the pieces of tape was 6 inches in width, the other 4 inches.
I also applied two layers of 10 ounce tape to the joint between the shelf and hull.

With everything ready to go, I mixed up the epoxy and wet down the joints on the starboard side with neat epoxy. I used RAKA brand epoxy - 127 resin and special 350 hardener. I thickened the left-over epoxy with colloidal silica and spread it on the bracket for the shelf. Then I screwed the shelf into place. Finally, with more left-over thickened epoxy in hand, I created a fillet along the joint between the bulkhead and the shelf. This would add strength to the joint, and it would allow the cloth a gentle transition between the vertical and horizontal.
Next, I mixed up another pot of neat epoxy and then lay down the first layer of tape on the joints. This cloth tape I wet out until all the bright white of the weave disappeared.
Then I applied the second later of tape and wet it out.
When I was finished with the second wet-out, I mixed colloidal silica into the epoxy until it reached the consistency of catsup. I used this mixture to give the tape a smooth consistency by completely filling in the weave of the cloth. This would make my sanding of the tape much easier.
Next, I grabbed some vinegar so as to wipe up the drops of epoxy that had fallen on the shelf during all of this. Vinegar does a fine job of cleaning up epoxy and is much less expensive and much less toxic than acetone.
In order to hold the shelf firmly in place on top of the blocks that I had previously glassed to the hull, where I had also applied thickened epoxy, I weighted down the shelf with a dumbbell during the curing process.
The next day I began to focus on the port side shelf. I began by pre-drilling holes for 1/4 inch flat-head wood screws that I would use to help secure the shelf to the blocks that I had previously glued to the hull. Unlike the starboard shelf, which would hold lightweight fenders, the port side shelf would hold the reserve battery. I wanted this shelf not only to be glued to the blocks, but also screwed.

It took several different measurements for me to figure out exactly where I needed to drill the holes. Due to the odd angles, it was hard for me to tell if I was on the mark. Fortunately, I hit the right spots - those thick ends of the blocks where there were several inches of material available for sinking the screws. If I had hit the upper parts of these blocks, which where wedge-shaped and thin, then I could have drilled all the way through the blocks and thus all the way through the hull.
While I was still in this dry-fitting and pre-drilling stage of this part of the project, I put my Rockwell Sonicrafter oscillating tool to work.
The cleat that I had earlier glued to the bulkhead was now much longer than I had originally thought it needed to be.
You would think that it would be hard to over measure it by this much. The reality is that it was difficult for me to judge exactly how long the cleat needed to be. Remember that I was dealing with a curved hull and that it was difficult to get my various dry-fits just right.
The Rockwell Sonicrafter took care of that excess in nothing flat.
Now the joint would be square and flush.
The task that remained was to glue the shelf permanently into place.

On this side I had to work around one of the cleats that I installed on the hull.

After I had allowed the epoxy on both sides of the lazarette to cure for 2-3 days, I returned to the boat with two important tools in hand - my Dremel (with a sanding drum attached) and my Rockwell Sonicrafter (also with a sanding head attached).
Earlier, as you'll recall, I glued a piece of plywood on the stern to reinforce this area for the Yamaha 9.9 HP High Thrust motor. It was a real bear sanding the biaxial cloth in this tight area of the lazarette. If I did not sand it, however, I could not be assured that the Pitthane two-part polyurethane that I would apply to the lazarette would adhere.
Next I sanded the port and starboard shelves. This was much easier, but it was still a nasty, time-consuming job.
I did this work in August, and I can assure you that this work area was far more hot and humid than it was outside the boat, where it was a more comfortable 95 degrees Fahrenheit.
At this point I felt that I had reached a milestone. At last I could begin to work on painting the lazarette and transforming this space into bright and easily visible area for the electrical and plumbing that I planned to add to it.

This ends this posting on how I glued-up the port and starboard shelves in the lazarette of Oystercatcher, my Ericson 25.

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