Knocking things off the List

We stopped by the boatyard a couple of times last week while down in Diggs, Va visiting John's sister.  Things are moving along on the inside of the boat while it is inside the shed and out of the weather.  A new issue came up during the work.  It turns out that the CruiseAir unit in the back of the boat that services only the aft berth is the bigger of the two units. Paul has an idea how to run a supply duct to the main salon at the base of the nav station.  That will help the unit run more efficiently as it needs to be pushing a higher volume of air and it will help cool the galley area.  Paul is also going to work out channeling more of the air from the return duct to the unit so that it does not pull it from the aft lazarette.  The forward unit return air flow is around the drawers under the berth...not really a direct and sufficient return.  Paul suggested converting one of the drawers to a return duct and we reluctantly agreed that seemed to be something we should do (don't like giving up the storage).

The first day we stopped by, Paul had the spreaders ready for painting and the next day we saw the completed job.

The boom repair was also painted.

Here is the piece that was removed from the end of the boom.

The bilge has been cleaned.  You can see where the washers worked their way down into the bilge material. 

This is the cleaned off surface of the keel stub on the hull. 

The top of the keel and keel bolts have also been cleaned...I don't have photos of that.

Boom Repair

Paul sent me some photos of the repair at the gooseneck end of the boom.In previous post, I had a photo showing how it had cracked along the gooseneck plate where it attaches to the boom.  The bottom section of the boom is carbon fiber and is solid, only the upper section needed repair.

Good News on the Keel Bolts

I got a drawing of the keel and keel bolt layout from Tartan which Paul forwarded to Jim Taylor.  He then got the data he needed to run through an American Bureau of Shipping (ABS) keel bolt routine that is an industry standard which Jim has been using for decades.  The result of this calculation gave a minimum base bolt diameter of exactly 0.50”...the size of the smallest bolts that are used on Owl Moon.  The bottom line from Jim is that that "the bolt diameters and locations do appear to be adequate to take the expected keel loads" (of course, that should have been the findings as the Tartan 4300 is CE approved for category “A” unlimited offshore).

Jim recommended the following keel installation and attachment steps:

 

- Carefully checking the condition of each keel bolt for cracks, pitting, etc.

- Cleaning and leveling both the top of the lead and the bottom of the keel sump.

- Developing a good mate between these two surfaces by ‘buttering’ both surfaces with wet epoxy, and dropping the hull down onto the keel with a release agent between the two, and allowing the epoxy to cure.

- The hull would then be lifted off the keel again, the two surfaces ‘buttered’ this time with a thin layer of 5200, and the hull again lowered back in place for long enough to allow the 5200 to cure fully.

- All of the keel bolts should be fitted with sizeable SS (or G-10) backing plates, not just simple washers.  The bottom edges of these plates should be radiused (softened) so they don’t cut into the glass. These plates should also be ‘potted’ in epoxy so that there are no voids underneath, and so that the load is spread evenly over the plate.

- The bolts should be properly torqued, according to their diameters.

This is more or less the steps that Paul had previously discussed with us.

The Keel Comes Off

July 29, 2016  I spent the night with my sister and brother-in-law, Susan and Coleman, at their place nearby in Diggs, VA.  Susan came with me to the boatyard Wednesday morning.  We arrived in time for me to give Susan a tour of Owl Moon while the yard workers were busy launching a boat.  Then came the big moment of lifting the hull off the 10,000 pound keel.  The hull lifted off the boat without the slightest hesitation.

This shows the gap immediately after lifting the boat.  Note the long run in the aft part (left) where there is no keel bolt.

Tartan had not used 5200 to bed the joint, but rather some other type of calk.  Paul thinks it is similar to what he uses to calk teak decking.  Interesting since Tartan recommended to us that we bed with 5200.

Forward portion of the keel stub with the centerboard line hanging down.

Aft section of keel stub.

Centerboard viewed from the top of the keel.

Owl Moon lifted clear of the keel and bolts.

Looking down the length of the keel from the aft end.

...

They transferred Owl Moon from the travel lift to hydraulic trailer in order to move her into the work shed.

Moving Owl Moon into the shed.

She fits!

They blocked her in the shed and now will be able to work on the list of things to be done.  After cleaning off the keel stub, keel bolts and top, and the bilge, Paul will take some more photos and assess the situation.  We will be consulting with yacht designer Jim Taylor on the keel bolts before moving forward with reattaching the keel. 

All Set to Drop the Keel

June 28, 2016  I drove down to Regent Point Tuesday afternoon so that I could be present when the dropped the keel first thing Wednesday morning.

The keel is braced, ready for lift off.  Calk at the edge has been removed and debond has been sprayed into the crack.

They have also removed all the nuts and washers from the keel bolts.  Before removing, they checked the tension and all the small nuts were way below the spec.  On many of them, the washers had settled into the floor of the bilge.  The torque on the medium nuts were also consistently off a bit.

Some other work has been done since I was last at Regent Point...

They removed the spreaders from the mast and saw that they were held in place with anodized aluminum bar that protects the aluminum spreaders from contacting the carbon fiber.

Anodized aluminum bar to anchor the spreader.

They also removed the paint from one of the rough spots on a spreader and were able to determine that the uneven surface was caused by failed paint and not any galvanic corrosion.  Regent Point will sand and paint the spreaders while they have the mast off the boat.

All the U bolts for the mainsheet blocks have been removed from the boom.  They did that by tying a string to the U bolt, removing the bolts that hold the backing plate in place and letting them drop down into the boom.

Bottom of the mast where one of the cover plates had been.

The three U bolts on the plate that had been inside the boom.

U bolts are welded to the plate that is inside the boom

Paul says he can reuse the plates and install larger diameter U bolts.