Centerboard, Installation

Oystercatcher's new centerboard shortly after installation
The installation of a centerboard in an Ericson 25 is not an overly difficult task, but it is one that requires some exertion, some patience, and, without a doubt, some assistance from another person. I installed a new centerboard in my Ericson 25, Oystercatcher, during a long and busy weekend that saw me tackling several related projects concurrently. Speed was important during this four-and-a-half day weekend. A friend of mine, who owns a small, land-locked boatyard in Charleston, South Carolina, had agreed to allow me to use his yard from late Friday afternoon to early Monday morning to bottom paint Oystercatcher and install a new centerboard in her trunk.

Below you see the boat temporarily tented to protect the deck from rain and to protect me from the oppressive Carolina sun. The centerboard sits atop sawhorses, wrapped in plastic, awaiting installation.
A lot of work had led up to this moment. Soon after I had purchased the boat and sailed her to Oriental, North Carolina for haul-out, I had the boatyard there remove the old centerboard from the trunk. As you can see in the picture below, it was not an easy job. For more on this part of the story, see my article, "Centerboard Extraction and Analysis."
I tried to save the old board by cleaning it up and letting it dry out. In the end, though, this was not enough. The saltwater that had penetrated the board caused the steel within to rust to such a degree that repairing the board was not possible.
After a lot of time, effort, and money I was able to create an entirely new board as close to the original shape and specifications as possible. The only thing from the old board that I reused were the two pieces of lead and the stainless steel tang. For more on this lengthy project see my nine-part article, "Centerboard Construction."
That lengthy centerboard-construction project ended with the application of bottom paint. This would be the same paint that I would use for the bottom painting of the boat.
One final centerboard-related project that I needed to complete before I could install the new board concerned the centerboard pin. The old one was pitted from spending its lifetime in saltwater. A friend of mine who is an adept amateur welder of stainless steel made a new one for me in about an hour's time in exchange for some beer. For more on this, see my article, "Centerboard Pin, Old and New."
This stainless-steel welding friend was also the one who helped me with the metalwork necessary for the construction of the centerboard. We improved the design of the original board by adding a piece of stainless steel tubing to the spine at the point where the centerboard pin would penetrate the board. The original board did not contain any tubing. As a result, water had slowly crept through the hardened foam that surrounded the steel. The tubing would prevent this. It was my friend's idea to make the tubing larger than the pin itself. He said that by making it larger I could install synthetic bushings that would allow the centerboard pin to pivot more freely, without there being steel-to-steel friction.
Now that the new centerboard was finished and the time had come to install it, I broke out bushings for the purpose of test-fitting them. They fit just right.
The centerboard pin also fit just right.
I also wanted to test-fit the centerboard pendent. As I said above, one of the pieces that I reused from the old centerboard in the construction of the new one was the stainless steel tang. The tang, as you see, contains an eyelet. It's through this eyelet that the clevis pin for the pendent passes. This was a new pendent - one that I had paid a local rigger to make for me. Therefore, it was especially important that I test-fit the pendent in advance of taking the boat and the centerboard and all these other pieces to the boatyard.
During the glassing of the new centerboard I had wrapped the tang with cloth as a precaution against water intrusion in this area of the board. I had gotten just a little too close to the eyelet, so now it was time to sand off some of the cloth to make room for the pendent.
I also wanted to make sure that the new centerboard pin would fit well in the old hole. Fit well it did. In fact, it fit so well that it was impossible to insert it and remove it without using tools.
Specifically, it required one person on one side with a deadblow hammer and a Phillips head screwdriver, and another person on the other side with a pair of channel locks.
Marine lubricant was also a must.
One additional preparatory task that I needed to complete was the temporary rigging of the pendent to an improvised block and line. This block and line would be necessary for lifting the centerboard up into the trunk after it was installed. The pendent and the block-and-line, as you see, are normally concealed within the mahogany mast step.
You cannot see it in this photograph, but there is a hole that leads upward to the mast step proper on deck. Within this mast step is a another block. The line runs up and over this block. From there it runs aft to a winch on the starboard side of the companionway. Without this set of blocks and this winch, the lifting of the centerboard is impossible.
Yes, there was a lot of preparatory work that went into the installation of this new centerboard. Aside from that which I have outlined above, I also had to install a trailer eye (bow eye) in the hull. For more on this, see my article, "Trailer Eye (Bow Eye) Installation."
The installation of the trailer eye (bow eye) was necessary for the lifting of the boat off of the trailer. For the details of this interesting job see, "Trailer to Jackstand Transfer, or How to Lift a Sailboat off of a Trailer with a Gantry."
Of course I had to bottom paint the boat, which involved scraping and sanding and rolling . . . and lots of sweating. For more on this, especially on how I scraped and painted the centerboard trunk, see the article, "Hull, Bottom Painting."
Oh yes, and one last thing . . . I had to construct a new keel skid to replace the old dunnage that the boatyard in Oriental, North Carolina had installed as a temporary measure for supporting the weight of the boat on this new trailer. See the article, "Trailer, Keel Skid Modification," for more details.
Did I say it was a long and busy weekend? I believe so. Well, once I had accomplished all of these other tasks, the time at last had come for me to install the new centerboard. It was late in the day on Sunday, much later than the time I took the photograph below.
One problem I ran into immediately was that I could not install the clevis pin in the tang. My hand sanding of the tang back at home had not been sufficient. The electric sander did the trick.
A beefy buddy of mine whom I'd called upon to help me with the installation of the centerboard didn't object at all when I asked him to help me carry the centerboard over to the scale in the boatyard. In fact, he picked the board up by himself as if it were just a piece of common lumber.
I was very curious to know just how much this new centerboard weighed. If you read the original literature for the Ericson 25 (see "Centerboard, Diagrams, Original), you'll see that the original centerboard was supposed to have weighed 150 pounds. If you click on the image below to enlarge it, you'll see that the scale in this photograph reads "125." This did not make sense to me at the time, and it does not make sense to me to this day. Why? I constructed the new centerboard to the original specifications, and, as I said above, I used the original lead plates and the original stainless steel tang. Moreover, I made some modifications that should have put the weight up over 150 pounds. For example, I used 3/16 inch carbon steel for the spine instead of 1/4 inch. I also, as I explained, added the stainless steel tubing to the spine for protection. The only thing I used that would have been lighter in weight than the original was the pour foam. I used pour foam that was of an 8 pound density. The original was perhaps (and I'm just guessing on this) of a 16 pound density. I believe this was the case, because the original foam was much more dense than the new foam. Nevertheless, I can't see where the limited amount of foam that I used in the new board would have made that big of a difference, especially since any difference in the weight of the foam would be offset, I believe, significantly by the additional weight of the 3/16 inch carbon steel spine and the stainless steel tubing. Perhaps the lead plates that were used in my 1975 centerboard were lighter in weight than the lead plates made in 1972 or 1973, when Ericson first began to manufacture the Ericson 25. Perhaps the stated 150 pound weight of the centerboard in the original literature was a typographical error. This will all remain mere speculation until someone else weighs his or her original board, so that there is some data for comparison.
The first thing my beefy buddy and I did after weighing the centerboard was to place it in the position you see in the picture below. It was at this point that I joined the pendent to the tang of the board with a clevis pin.
It's difficult to see in this picture, because the picture itself is backlit, but the clevis pin was held in place by a cotter ring. One other thing that I had done on this busy weekend that I've not yet mentioned was to purchase a new clevis pin and a new cotter ring from a local chandlery. These pieces of 316 stainless steel were a little pricey, but I was not about to go cheap and reuse old hardware after all of the time and money I'd spent to get to this point.
My buddy and I began by propping the board into place as you see in the picture below. We had determined after a few tries that the board needed to be at this angle in order for us to insert the pin.

When everything seemed good to go, I grabbed the new pin and the marine lubricant. I use the word seem here, because we actually had to make some adjustments to the angle of the board in order to get the hole in the hull and the hole in the board to line up just right.
We ended up propping the board up with a small jackstand and a couple of wedges. This slightly different angle was just what the board needed. If you read the article, "Centerboard, Basic Observations," you'll understand why it's important to get the angle just right. There is an angled pocket inside the trunk into which the angled head of the board fits. For good pictures of this angled area in the trunk, see my article, "Hull, Bottom Painting."
The picture below offers a good view of the flared edges of the centerboard trunk. These flared edges protect the centerboard, and they serve as a small keel of sorts upon which the boat rests when it sits upon the keel skid of the trailer. For more on this, see my article, "Trailer, Keel Skid Modification."
It was nice finally to have this new centerboard in place. I did not, at this time, secure the pin by installing screws through the holes on either side of the pin. I wanted to use 316 stainless steel screws, and the local chandlery did not have any of the appropriate size at this time.
One last thing that I needed to do was to make sure that the new centerboard actually fit within the centerboard trunk. I had made precise measurements of the old board before destroying it. I had also measured and remeasured the trunk while I was glassing and sanding the board. Fortunately, there was sufficient room for the board, and I was able to winch it up into the trunk without a problem. I did not get a picture of the board in the stowed position, because I was in the cockpit. Notice the optical illusion in the picture below. The reflection of light off of the wedges make the centerboard appear as if it has a curve in it.
Despite the Sunday evening thunderstorm that has passed through while we were doing all of this, my buddy and I had successfully installed the new centerboard. Now, all I needed to do was to transfer the boat back to the trailer when the boatyard reopened the next morning.
This ends this article on the installation of a new centerboard in Oystercatcher, my Ericson 25.

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