Wednesday, July 12, 2017

Rebedding the Chain Plates

We found a Leak - that's never good on a Sail Boat!
Water was running down the Chain Plate rod between the Deck and the Holding point on the Lower Aft Shroud Chain Plate.
No Surprise! That's Silicone Caulk around the Chain Plate and Securing Bolts on the Deck Port Side.

The Silicone has Shrunk over the past few years and finally gave way on the Port Aft Chain Plate during recent heavy rains.

Time to remove, Clean and Re-bed the Chain plates.







Step 1 was to disconnect the chain plate from the Lower Aft Port side Shroud. After seeing the failure of the Lifeline turnbuckle just a couple of months ago, I was anticipating problems with being able to release the strain on the Turnbuckle. So I gave it a prolonged treatment of PB Blaster. Basically I sprayed PB Blaster onto the threads of the Turnbuckle and then wrapped them in Paper Towel, then applied more PBB to the wet paper towel hoping that keeping the area damp with PBB would do the trick (make it easy to unscrew the turnbuckle) - That worked a treat! After leaving them soaking for several days, it was easy to unscrew them and release the Shroud cable supporting the lower section of the Mast.

Once the turnbuckle was easy rotated, I noted the thread count on each end and then completely disconnected the turnbuckle from the chain plate by removing the cotter pin as seen above.

It took about 20 minutes to clean the silicone from the deck. The good news was that a previous owner had taken the trouble to protect the edges of the 3 holes (plate and securing bolts) with Fiberglass Resin. So once cleaned it would be easy to reinstall the plates.

Here's what the chain plate looked like before cleaning.
That brown crud is just surface corrosion and the white crud on the plate is the residue of an earlier attempt to water proof the plate to deck connection.

There's more crud around the bolts and washers.







After clean up and treating the surface corrosion with Spotless Stainless.

Careful inspection of the cleaned plate with a magnifying glass confirmed there was no apparent crevice corrosion where the Plate Tab is welded to the Plate, nor on the underside where the Rod Connector plates are welded to the Plate.

So I get to reuse them, just as well, they cost about $150 each!




Here's the 1st of the plates, cleaned, sealed with Butyl Tape and, with the help of Peggy in the Cabin, secured to the deck.

Looks so much better and you can barely see the Butyl tape that is under the fender washers and the Tab Plate.

The turnbuckle is re-tensioned and I'm very confident that this will cure the leak and last a long while - at least a couple of years.





With #1 out of 6 done, I started on the other 5 today. PB Blaster soaking the turnbuckles.

Plan is to complete the re-bedding of the remaining 5 chain plates over the next week, then it's time to re-tension the rig - will need a Loos Gauge for that. Hopefully a I'll find a club member that has one and can help out.

See you on the Water.