Lazarette Modifications, Part 13: Gluing Up the Battery Box Cleats

The battery box cleats, glued-up and sanded
Having completed the initial painting of the lazarette and having installed the necessary hardware on the battery box shelves, it was now time for me to glue-up the battery box cleats in Oystercatcher, my Ericson 25.

I began by clamping the conduit for the VHF coaxial cable. I had to get this plastic conduit out of the way. Otherwise, I would have gotten epoxy and cloth on it.
With this out of the way, I started to cut cloth. I used 12 ounce biaxial cloth that I had purchased from RAKA epoxy in Florida.
I cut two small pieces for the joints at the base of the cleats.
I then cut two large pieces, which would overlap the cleats.
Although I had checked the house bank battery box shelf for level many other times, I just had to do it one more time before doing this epoxy work.
The level shelf helped me figure out exactly where I needed to install the cleats. I held the cleats, one at a time, under the shelf with one hand and marked the hull with the other.
For this project, as on so many others, I used RAKA 127 Low Viscosity Resin and 350 Special Non-Blush Hardener. I don't mind paying $12 extra for the 350 hardener, because it prevents me from having to clean off the amine blush from the work surface a day or two after the epoxy cures.
I had cleaned this area many times, but I still gave it a good wipe-down with acetone to remove any dust that might have settled here.
Once I had cleaned the hull, I mixed up 3 ounces of epoxy and wet out the appropriate areas of the hull with a brush
Then I wet out those sides of the cleat that would make contact with the hull.
I let this epoxy sit for about an hour so that it would become nice and sticky. This would improve the adhesion of the cleats to the hull during the glue-up. Then I mixed up another pot of epoxy, this time making 6 ounces - four ounces of resin and two ounces of hardener. In the picture below, you can see the hardener sitting on top of the resin. The hardener is yellowish, whereas the resin is more clear.
I have never timed myself in my mixing of the resin and hardener, but I would say that I do it for at least two minutes, making sure to scrape the sides of the pot throughout the mixing process.
It takes two-and-a-half to three scoops from this quart-sized container for me to thicken up the epoxy to a peanut-butter consistency - the consistency needed for gluing up things.
When thickening 6 ounces of epoxy, I therefore must use around 6 scoops. As I've said before, I use a large, 5 gallon bucket to store my colloidal silica, and I use the quart sized container in the picture below to distribute the silica. If I purchased the silica one quart at a time from somewhere like West Marine (as I did the very first time), I would spend a fortune on it.

I never add all of the silica at one time. Instead, I add it about two scoops at a time. This allows me to thoroughly mix the silica into the epoxy.
If it clings to my stir stick without the slightest bit of drooping, then I know it's thick enough.
The reason why I felt at leisure to take all of the above pictures is because I wanted to take my time in mixing up this epoxy. This would allow it time to heat up and thus become more sticky for this glue-up. I've described this technique of "sweating the pot" in earlier postings on my gluing-up of cleats. The trick is to stir it and stir it until you start to feel it get nice and warm in your hand. Then you quickly start to spread it onto the hull, or whatever it is that you're working on. This will keep it from getting too warm. If it gets to the point where it starts to feel hot in your hand, you might have waited too long. This is a called a "run away pot." It gets so hot that it smokes, and it moves from being a viscous liquid to a solid in a very short period of time.I had this happen to me the very first time I mixed up a pot of epoxy. Fortunately, I was not in the boat, but in the yard when this happened. The pot got so hot that I had to throw it away from me to prevent it from burning my hand.
Despite the steps I had taken, this cleat still had a tendency to slide slightly after I had stuck it into place. This was due undoubtedly to its size. To give it a little help, I applied some duct tape.
Before I had applied the duct tape, I had laid down a fillet along all four edges of the cleat. The fillet would improve the strength of the joint, and it would help provide smooth transitions for the cloth.
After I had completed the glue-up of the first cleat, I mixed up 6 more ounces of epoxy and focused on the second cleat.
Two or three hours later, when I was confident that the cleats were no longer going to move, I carefully removed the duct tape and prepared to lay down the cloth. First I laid down the little pieces and wet them out with neat epoxy. Then I laid down the large pieces and fully wet them out. I used at least 6 ounces of epoxy in this wetting out of the cloth. Biaxial cloth is like a thirsty sponge.
After I had fully wet out the cloth, I mixed up another 6 ounces of epoxy and thickened it to a ketchup-like consistency. With a brush in hand I spread this thickened epoxy over the cloth for the purpose of filling the weave and thus providing additional strength.
The next day, I was pleased to see not only that the shelf fit well into this space when placed atop the cleats, but also that it was level.
Now it was time for me to do some pre-drilling for the installation of the battery box shelf.
I purchased 1/4 inch stainless steel flathead screws from the local hardware store, and I used a 3/16 inch bit to drill the pilot holes.
After I had completed the drilling, I used a countersink bit to bevel the holes and thus provide a recessed area in the shelf for the heads of the screws.
After the epoxy had cured for two or three days I returned to the boat and prepared to sand the area.
I had already completed most of the rewiring of the boat. The last thing I wanted on this new electrical system was a bunch of epoxy dust. Therefore, I took the time to tape up some plastic. Below we see the port side of the lararette.
I also taped the center part of the lazarette, where many wires ran back and forth from the two sides.
Likewise, I taped plastic over the electrical components on the starboard side.
I also shoved towels and rags into the area between the icebox and the bulkhead. There were a lot of wires running up through this space into the cavity behind the bulkhead on the starboard side of the galley (where the battery charger was located).
Additionally, I taped plastic over the hole for the storage area under the galley sink. This was the last sanding of epoxy that I would undertake in the refitting of this boat, I was glad that it was almost over, and there was no way that I was going to let that dust get into some of the areas that were already finished. You'll recall that I had to postpone this epoxy work until after I had completed the rewiring project, because I needed to be able to sit in the bilge area (where the battery shelf would be located) while doing a lot of the rewiring.
To accomplish this sanding job, I used my Dremel with a 50 grit sanding drum, my Rockwell Sonicrafter oscillating tool with 50 grit paper on the sanding head, and I used my Dewalt quarter sheet sander with 40 grit paper.
At the end, I also had to do a little hand sanding with some 40 grit paper in areas around the joints where the Dremel could not quite reach. This thorough sanding would ensure that the paint would bond well to all of this epoxy work.
This ends this posting on how I glued-up the cleats for the house bank battery box shelf on Oystercatcher, my Ericson 25.

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