Centerboard, Extraction and Analysis, Part II

Centerboard with Bottom Paint Removed
The second part of this two-part article on the extraction and analysis of the original centerboard from my Ericson 25 is concerned not so much with the extraction of the board (which was the primary subject of Part I), but with the analysis of it after it had been removed from the boat. You'll recall in Part I, that the centerboard was stuck so tightly within the centerboard trunk that a boatyard worker had to pry it out with a crowbar (and with a lot of upper-body strength).
You'll also recall that the reason why the centerboard was stuck within the trunk was because uncured bottom paint on the side of the board had bonded with the bottom paint within the trunk. The black marks here are an indication of this.
That the board had been stuck within the trunk on account of the bottom paint and not on account of the swelling of the board (due to the rusting of the steel spine within the board) was a cause for some joy. This meant that there was some hope for repairing the board and putting it back into service. The boatyard owner said he could do some fiberglass repair work on the board and get it back into good working order for about $300. I wasn't up for accepting this offer, especially since it would require me to drive over six hours up the coast from Charleston, South Carolina to Oriental, North Carolina to pick it up after the repairs were complete. Oh yes, and then I would need to drive six hours back down the coast to get back home.
Other owners of the Ericson 25 have not been as fortunate as I was when they first took possession of their boats. Many have discovered that, due to neglect on the part of the former owner, the centerboard has swollen so much within the centerboard trunk that it cannot be removed without a Herculean effort. Below we see a picture of what exactly one new owner faced. Here you are looking at that part of the board where a stainless steel pin holds the board securely within the trunk. We'll call this the head of the board. This eyelet within the head is a common point of failure in the centerboard of the Ericson 25. Water within the pin hole (that passes through the board) slowly penetrates the polyester resin and cured pour-foam over time and eventually reaches the steel spine. When this happens, the board swells and cracks, just like board we see here in the picture.
Another problem spot on the Ericson 25 centerboard is the opposite end of the board - the foot of the board if we wish to call it that. This end of the board gets the most abuse, since this part, obviously, is the part most likely to make contact with the bottom when sailing in shallow water. One too many times of this, and the next thing you know there is no more fiberglass there - only pour foam, and eventually that cured pour foam, regardless of its density, is going to allow some water to creep in there.
When it does creep in there, just as is the case with the head of the board, the steel spine of the board oxidizes, and soon the rust causes the board to expand. Below we see a better shot of the same board in the same boat as the two pictures above. The swelling of the board has caused it to become wedged within the centerboard trunk.
If left untended for a lengthy period of time, you end up with a board that this horribly swelled. The owner of this boat rigged-up a hydraulic jack to extract this board from this centerboard trunk. That's how bad it was.
Having decided that I did not want to pay the boatyard in Oriental, NC to repair my centerboard, I took my boat and my board back to Charleston, SC. There I consulted a buddy of mine at a local boatyard. He advised me to put the board aside for no less than three months to allow it to dry out. After all, it had been in the water for a very long time. Following his advice, I placed the board in a work room within the house.

During this dry-out period, I thought I would go ahead and get a little work accomplished on the board, so I took it outside one Saturday and ground off all the bottom paint. I knew that all of this stuff had to come off before I could do any repair work. The mottled appearance of the board in the picture below reveals three different layers. The gray is a barrier coat meant to protect the fiberglass from blistering. The white is the gel-coat, the original protective coating for the fiberglass. Beneath that is off-white fiberglass itself.
The next Saturday I had a buddy of mine give me a hand with his die-grinder. This was an excellent tool for grinding out some of the rusty cracks that were here and there on this board.
Below you can see some of the areas of the foot of the board that he cleaned out with the die grinder. Unlike my angle grinder, this pneumatic die-grinder could get into tight spaces and make good progress against the rusty steel.
Another area at the foot of the board.
The picture below gives you a good idea of just how much fiberglass had been lost off of the foot of the board over time. Notice that the lead plate protrudes from the foot of the board.
Here's an even better view of the damage at the foot of the board.
My buddy did the best he could with what he had to work with. Here you see that he's ground the metal down to make it flush with the foot of the board.
He also ground out the area that had been damaged by the crowbar that the boatyard worker had used to extract the board from the trunk.
At this time I made sure to write down some of the dimensions of the board before we got too carried away with all the grinding we were doing. I determined with the calipers that the average thickness of the board was 2-1/4 inches.

Having addressed the foot of the board, we turned our attention to the head. There we made some troubling discoveries.
It was obvious that a former owner had experienced problems with the head and had done some repair work in this area. There were many cracks and fissures that had been concealed by the bottom paint and the other protective coatings.
All of these cracks appeared to have stemmed from the problem area around the eyelet for the centerboard pin. There was also a major crack along the leading edge of the board not far from the pin. You can see the crack on the ride side.
Once again, just as he did with the foot of the board, my buddy did the best he could to grind out the rusty crack in this part of the board.
With the grinding of the problem areas complete, I took the board back home and put it back in the work room. There, I planned to let it sit some more, so that it would completely dry out. I never took a picture of it on its drying rack (in its post-bottom-paint state), but this what it looked like - at least initially. Eventually, I propped it up against the wall so that the leading edge of the board (where the major cracks were located) faced downwards. I figured this would help direct any water that might be in there downward and thus outward.
Meanwhile, I consulted long-time E25 owner, Rob of Wisconsin, to see what he thought about how I should proceed with the repair of my centerboard. I knew that he had made similar repairs, and I valued his advice. The foot of his board, as seen below, had looked very similar to the foot of my board.
Rob used cloth and epoxy to cover the wound, and then sanded it and painted it. Below we see the results of his work on the foot of his board.
When it came to repairing the head of the board, Rob decided that the best way to keep this old board serviceable was to reinforce it with an aluminum plate.
He urged me to do the same. I thought this was a good idea, especially since he reported that he had never had anymore problems with his board. Note that this plate not only reinforces the head of the board, but also the eyelet.
It's worth pointing out that Rob's solution to the problem is one that someone at Ericson Yachts had envisioned back in the 1970s. Whether or not any Ericsons were manufactured with such a plate is questionable. I've yet to hear of one, but that does not mean they don't exist.

Yes, my plan was to let my board fully dry out and then do the repairs in a way similar to Rob of Wisconsin. At the time, however, I was very distracted by a major home improvement project, and it turned out that I did not return to the centerboard for at least 1.5 years. It's not that I didn't do other work here and there on the boat at that time, but I just didn't have the time or the will to tackle this project when I had so many other projects that I needed to complete on my house. As it turned out, this waiting game took a toll on the centerboard. When I finally was able to turn my attention to it again, I was horrified to discover that, despite all the cleaning and grinding that I had done on the board, and despite the fact that it had sat in a climate-controlled workroom for the entire time, it had continued to swell with rust from within. The exterior of the board was no longer the normal 2-1/4 inches, but a grotesque 2-3/4 inches in the area around the head. With much regret, I determined that the board was a complete loss, and it was at this point that I realized that I had no choice but to construct a new one. The lengthy process of building a new centerboard to the original specifications is the subject of my four-part article, "Centerboard Construction."

This ends this two-part article on the extraction and analysis of the original centerboard for Oystercatcher, my Ericson 25.

Ericson 25, Centerboard, Deployed and Stowed

An Ericson 25 in the Slings, with Centerboard Deployed
If you've read the brief article on the original centerboard diagrams for the Ericson 25, you'll remember that the diagrams show the centerboard deployed in the fashion depicted below. In this fully-deployed position, the angle of the board relative to the waterline is approximately 45 degrees.

Below we see an Ericson 25 owner using an unconventional method for the launching or hauling-out of his boat. For some reason or another he has deployed his board rather than winching it up and stowing it in the centerboard trunk. Regardless of his intentions, we can see that the board stands at approximately a 45 degree angle.
Likewise, we see in the photograph below that the centerboard on this Ericson 25 is also deployed at what appears to be a 45 degree angle.
 This boat, sitting on jackstands on the hard, also has its centerboard deployed at a similar angle.
This person is obviously making sure that his board is just as clean as his hull just after haul-out. Again, we see the centerboard deployed at a 45.
Same goes for this boat.
When the centerboard of the Ericson 25 is in the fully-stowed position, it is protected by the centerboard trunk and the boat is capable of resting on blocks, as is this boat, sitting in its cradle for the winter.
It's easy to see the centerboard in the picture below. Likewise, it's easy to see that the boat has no problem resting much of its weight directly on top of the centerboard trunk.
This boat sits on blocks and jackstands in what appears to be a winter-storage facility. Note that the owner has opted not to block the centerboard trunk. At the same time, he has opted to partially deploy the board. Perhaps he did this out of concern that the board might swell while in storage and thus become stuck within the trunk. Perhaps, though, his board was well-cared for, and he did this simply to provide some ventilation in this area during the months the boat was in storage.
This concludes this brief article on the deployment and the stowing of the centerboard on the Ericson 25.

Ericson 25, Centerboard, Diagrams, Original

One of several original diagrams illustrating the basic specifications for the Ericson 25 centerboard
While some owners of the Ericson 25 - those with the fixed-keel versions of the boat - never need to think about issues involving the centerboard, most owners of the Ericson 25 do. For those in the latter category, the following information will be of much use. I should note before letting this information speak for itself, that I've never heard of an E25 centerboard possessing the stainless steel reinforcing plate that is pictured in the diagram below. Apparently, though, some of them were made in this fashion. I would have to wager that this was an afterthought on the part of Ericson Yachts, and a good one at that, because this portion of the board (where the stainless steel pin passes through the board) is the most likely area where any owner would experience a failure. This area, without such a plate, is weak, insofar as the pin hole in the board is supported not by metal, but by cured pour-foam and mat and cloth soaked with polyester resin. More than one owner has lost a board due to a failure in this area. One final note . . . if you wish to enlarge any of the below diagrams, simply click on the image.