We removed our centerboard on Thursday. From everything we've seen on this site and the Facebook group, we feel pretty good about winning the prize for Most Corroded Hinge Bolts. Most of the ones that snapped off had a little bit of stainless holding the board in place, but it wasn't much. Only one bolt made it out of the keel. I'm guessing these are the original 1979 3/8 machine bolts. Our plan here is to replace the bolts with 1/2 lag screws as others have done.
The 1" bore in the board for the hinge pin has a visible crack. We're planning to dremel out some of that material and fill it with thickened epoxy. I'm nervous about making a more extensive repair that might leave us with a misaligned board, so I'm hoping we can keep most of the hole unaltered.
Most of the hinge itself looks OK, except for some nasty pitting in the hinge pin. We're planning to replace the hinge assembly since there's no telling how deep that cave in the pin goes.
Like jvoelxen, the padeye bolts had corroded and allowed water to enter the board, causing it to swell and crack. Following the posts on this thread, we started cutting open the board and chiseling out the solid resin looking for the infamous steel plate. There was a void behind the padeye, but we didn't find anything that looked like the residue of an aluminum backing plate. We also never found the steel plate: just resin with some water-filled cracks. We're planning to fill the board back up with West System epoxy (with a lot of 404 filler) then seal it up with glass (epoxy resin) and repaint the whole board with epoxy paint.
Instead of the padeye bolted into the board, we're going with Tortuga's method of external tangs and a shackle.
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File comment: damaged threads and a big cave
![hinge pin pit closeup.jpg](./download.php?id=2175&t=1&f=4&sid=afa4104b0f6f0914ff2c6b12059f9b8e)
hinge pin pit closeup.jpg [ 1.22 MB | Viewed 0 times ]
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File comment: Crevice corrosion pitting of the hinge pin
![hinge pin pitting.jpg](./download.php?id=2176&t=1&f=4&sid=afa4104b0f6f0914ff2c6b12059f9b8e)
hinge pin pitting.jpg [ 1.18 MB | Viewed 0 times ]
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File comment: bore crack detail
![board hinge bore crack detail.jpg](./download.php?id=2177&t=1&f=4&sid=afa4104b0f6f0914ff2c6b12059f9b8e)
board hinge bore crack detail.jpg [ 1.43 MB | Viewed 0 times ]
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File comment: crack on the ID of the hinge bore
![board hinge bore crack.jpg](./download.php?id=2178&t=1&f=4&sid=afa4104b0f6f0914ff2c6b12059f9b8e)
board hinge bore crack.jpg [ 1.91 MB | Viewed 0 times ]
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File comment: Not much left of the 3/8 bolts.
![hinge bolts.jpg](./download.php?id=2179&t=1&f=4&sid=afa4104b0f6f0914ff2c6b12059f9b8e)
hinge bolts.jpg [ 2.15 MB | Viewed 0 times ]
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