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| The new centerboard pin juxtaposed with the old |
With the exception of the handful of fixed keel versions of the Ericson 25, the centerboard is a vital component of this boat, and the stainless steel pin that holds it securely to the boat is perhaps even more vital. When I had Oystercatcher, my Ericson 25, hauled-out, shortly after purchase, the first thing that I asked the boatyard owner and his workers to do was to remove the centerboard from the boat. If you've read my two-part article, "Centerboard Extraction and Analysis," you'll know why I had to remove it. At any rate, before the removal could take place, the centerboard pin needed to come out. This was not an easy task, as you can tell by the exertion that is evident in the boatyard owner's face.
As the diagrams from the original yard manual makes clear, the pin consisted of a piece of stainless steel rod, 1/2 inch in diameter. This is the way the boat would appear if you were lying on the ground looking up at it while it was in the slings.
The original yard manual also makes clear that the centerboard pin was held in place by two #10 screws that were 1/2 inch in length. When the boatyard owner began the pin-removal process, he found a sealant of some sort that had been placed in the small cavities where the centerboard pin terminated near the edges of the hull. He dug this out and then removed the screws. The screws, were 1/2 inch in length, as they were supposed to be. From what I could tell they were this 1/2 inch length, becaused if they had been much longer they would have penetrated too deeply into the hull. The hull in this specific area might be thicker, but I know that the hull in general is 1/2 thick below the waterline.
After I had gotten the boat back home to Charleston I thoroughly inspected the centerboard pin and discovered that it had quite a bit of corrosion on it. Its condition mirrored the condition of the centerboard itself, which was suffering from having spent almost all of its 35 years immersed in salt water. Later, when I eventually decided to construct a new centerboard, I decided to make a new centerboard pin as well.
After I had made the new pin, I photographed it side by side with the old pin, so as to emphasize the extent of the corrosion.
The following pictures give you some idea of the some of the corrosion in some areas of the pin. Salt water will, of course, corrode even 316 stainless steel, if it is in an anaerobic environment. I would say that the snug pin hole in which this steel sat within the hull was anaerobic. This same sort of corrosion, of course, can and does occur on the 316 stainless steel chainplates in that area where they pass through the deck.
In order to make a new pin to replace the old, corroded one, I had to rely entirely on the good graces of one of my metal-working buddies. This was the same fellow who had helped me demolish my old centerboard and construct the new carbon steel spine for my new centerboard. He's usually happy to do this sort of work in exchange for beer, and I'm happy that he's willing to do it. When I called him up to explain my problem, he said to come on over, since he didn't figure this little project would take much time at all.
He started by grabbing a piece of 316 stainless rod and making a few measurements based on the old pin.
Then he took the rod to the band saw and cut off an 8 inch piece. The original measured 7-3/4 inches, but he wanted to make the new one a little longer so he had plenty of material to work with, especially when it came to cutting the angles on either end of the rod.
Next, he placed the old and the new side by side, so that he could mark the angle for each end.
Back at the bandsaw, he started cutting the angles in the hand-worked fashion depicted below.
After he finished the first side, he turned it around and cut the other side while holding the free end with a pair of vice-grips.
Having completed the angled cuts, he said he needed to clean up the metal in the areas around the cuts, so he took the steel rod over to the sawhorse and grabbed his pneumatic carbide burr.
This carbide burr really did a good job of eating away the rough edges of the steel and smoothing up the entire surface.
The next task was to drill the holes. Again, the old pin served as a reference.
Comparing the old with the new, you can see that the old pin has a much larger hole on the underside of the pin. This was because the Ericson yard had drilled out this area so that the #10 screw could be counter-sunk and thus be made to sit with its head flush against the surface of the steel.
To replicate this counter-sink, my buddy put the pin in his drill press and simply worked it with one of his large drill bits.
While it might seem, based upon the number of pictures that I took, that the fabrication of the new centerboard pin took a considerable amount of time. It did not. In fact, it only took about one hour.
Back at home, I compared the old with the new, and I was glad that I had taken the time to call my metal-working buddy and ask him for this favor. This was right about the time that I was almost finished making my new centerboard for my boat, and having a new pin for a new board made me feel that much better about all the labor that I had put into the centerboard project.
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