Pulling chainplates with the rig up

[Locquatious]

We had a chainplate failure last year while underway from Culebra to St. Thomas. It released the upper and mid shrouds on the starboard side. On each roll the top of the mast swung to port 4-5 feet, held in place only by the starboard lower shrouds. When it sprung back the mast was stopped hard pulling on the port shrouds.The break felt like we hit a whale or log so that was where we looked first. Then we saw the shroud flying with part of the plate.

First thing we did was backwind the jib. This forced the mast straight pulling against the forestay and port shrouds. Next we pulled both halyards down to the top rail tight. Then we pulled in the sails.

The mast still swung about a foot on each roll since the halyards stretched. We were not going to make it to St. Thomas based on how we quartered the waves to reduce the roll. So finally we swung the boom to starboard and prevented it tight to the top rail. Because we had a topping lift (many who have a boom vang will get rid of the topping lift), the mast was held tight and we could get a better angle on the waves, allowing us to get to St. Thomas.

We continued to replace chain plates while in the water, but on a quiet mooring. We do one at a time. Halyards tight to the top rail and boom prevented on the change-out side.

[billdre]

I suspect you already have your answer from the other posts on this thread. However, just to confirm. I replaced both chainplates two years ago. They needed to be fabricated and to be sure they were exactly the same I pulled them both and had it done at Schaefer. (Great job by the way.) Anyway, so my upper and one set of lower shrouds were off for several weeks while on the hard. It's a keel stepped mast. It was fine with fore and aft stays, the second set of lower shrouds in place and the upper shrouds somewhat taut, attached to the nearest stanchion bases.

[foufou]

I just replaced two chainplates a week ago. No big deal. These were the uppers on a two spreader deck stepped mast. I loosened only the ones I was removing. No need for halyards as an interim stay. All went well. The new chainplates are in place and tensioned back to the the marks I put on before loosening the rig.

[01kiwijohn]

I thoroughly cleaned the turnbuckle threads, then tightly wrapped good quality electrical tape around the threads, just butting up against the end of the turnbuckles.
When re-tightening, just turn them back until they just touch the tape edge.

[CarinaPDX]

Coat the threads of the turnbuckles with penetrating lube first. Once disassembled clean everything then put moly dry lube on the threads before reassembly.

I replaced my chainplates while in the water without problem. Just do one at a time, and carefully measure first so that the turnbuckles can be returned to the original tension.

Greg

[G3stanton]

I was recently returning from Panama City, FL. when the starboard sub deck chain plate parted, when all sails were up. I pulled into the 20 knot wind, slackened and dropped all sails, then moved the starboard stay to the nearby metal cap rail used to attach the jenny. We then motored through some nasty weather for the rest of the trip to St Marks with no mast problems. Keel set masts are hearty features. Yes, the Starratt Jenks (46 ft Morgan) has twin stays (upper and lower each) on each side which no doubt helped. I am now looking for anyone with knowledge of this 1978 boat that can show me pictures of their chain plates for guidance on my repair. I've sailed it since 1994.

[a64pilot]

You may want to start a thread with the title that says exactly what your looking for, if you don’t get good responses to this one. Good there was no dismasting.
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