Chain plates

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Sep 8, 2021, 1:20:05 PM9/8/21
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Just curious at this point. Has anyone pulled their main mast chain plates for inspection / replacement? With the rig up?
I did my backstay chainplate this past spring and at the same time removed a lot of moisture from the aft deck core that had been getting in there presumably from the chain plate slot and the rudder post access. That deck is now dry and the ingress points are permanently resolved but I still have moisture in the side decks extending 6-18 inches either direction from the main chain plates. I’d like to pull the chain plates one at a time with the boat in water and the rig remaining up. I could then deal with the wet core and (as I did with the backstay) replace the core around the deck slot with solid epoxy. Has anyone pulled the chain plates with their rig up?
My feeling is it would be fine given the solid nature of the keel stepped mast and a halyard or two dogged down as outboard as possible but please share your experience.

For anyone interested here’s more on drying the aft deck:

I started noting brown tannin stains on the underside of the aft deck in the aft cabin. A water meter told me I had moisture in the deck core in excess of 33%(max on the meter) in a large semicircle centered on the rudder post and or backstay chain plate.
I removed the chainplate. Cut out some core from below extending several inches around the opening and used thickened epoxy the glue in a solid piece of epoxy board. I used a bracing board on deck and temporary bolts through the slot and the epoxy board to really suck it up firmly and squeeze thickened epoxy out all around. I had to do the sam thing around the port mizzen shroud bolts as my wet semicircle was large enough to have reached this point. I hogged put around the rudder post deck penetration and forced thickened epoxy into the void to seal that ingress point as well.
From the underside I drilled 1/4” holes into the core in a grid spaced about 1 1/2”. I did small areas one at at tie, like roughly 1-2 square feet. Then used a vaccine bag on the underside with a 1hp high vacuum pump and heat pads on top of the deck at 100 degreesC. As soon as I had an area set up with heat and suction I’d start seeing water coming out my 1/4” holes. I kept the process going until the meter read below 10% then I filled the holes with thickened epoxy.
Now 3 months down the road the whole area reads 7 to 8% moisture. It was gratifying. The core was not rotted, just wet.
I plan to employ the same method to the much smaller affected areas of side deck while the chain plates are removed.


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Sep 8, 2021, 2:57:40 PM9/8/21
Has anyone pulled their rudder for inspection?


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> On Sep 8, 2021, at 10:20 AM, NICHOLAS SHAW <> wrote:
> Just curious at this point. Has anyone pulled their main mast chain plates for inspection / replacement? With the rig up?
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Jan 10, 2022, 10:39:12 PM1/10/22
to cal46
Just to update folks who may be interested , I have both chain plates removed. Both are in pretty good shape with only a very minor pit or two on each one. Not deep and I have no reservations reusing them. A couple of the bolts on the starboard side fractured ( from severe crevice corrosion) on removal. There was increased moisture ( from meter reading) in the bulkhead on the port side only which I have now dried out.
I’ve hogged out the deck core around both deck cutouts and the screw holes for the cover plates and filled the  cutouts and the undercuts with thickened epoxy. When we get a couple of nice days I’ll recut the deck slots and reinstall the chainplates.
As for the rig, I tied halyards to padeyes on the side decks but the lines are not very tight and likely given the keel stepped “tree trunk” of a mast not even necessary. 
I was really pleased the chain plates themselves are ok and I feel the job was well worth doing to inspect them and the bolts and the bulkheads that hold everything together.
I asked my son to add this to his diary to do it again in another 30 years. Haha
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