Centerboard of DOOM!

[DanaDCole]

Oh man, I am very curious about what happened! Did you manage to raise the boat enough? Did you use the low-tide-rollover method? Did you have to break out the scuba gear?

Also, what was jamming the centerboard? Nothing bad, I hope.

[DanaDCole]

One other idea if the low-tide one doesn't work (or doesn't give you enough time). Perhaps you could call your local equipment rental place and ask if you can bring the boat there and use a forklift there in their lot (and they'd probably have staff there ready and willing to help). You would still have to pay the rent, but would not need to transport it. You will need slings for the boat of course.

I don't know if you saw the post where John suggested the lift idea and shows a picture (not a PocketShip). Of course if you know someone who can get you the use of a forklift free, all the better.

[bobsastro]

Dana, I seem to have the same problem; stuck centerboard, and I will use the following proceedure:

1. Rent an "A"-frame or gantry (like a small straddlelift you can get from the local rental place, usually used for lifting cars or engines). Get one with a wide enough beam to fit the Pocketship between, and with a beam height of about 8 feet. Get it with a 1/2 or 1 ton chainblock.
2. On a flat driveway, put the gantry over the Pocketship just forward of the centreboard slot so the lifting sling lifts the bit of keel showing. Use a garage jack to jack up the back of the keel, then lift the front with the gantry chain block.
3. Pull the trailer out from under the boat, and chock everything safely
4. Access the centerboard, repair, whatever
5. Repeat the process to put back on the trailer

Cheers,
Bob Fuller

[bobsastro]

Hey guys, here's how to do it, if you've got a reasonable industrial rental outfit nearby. Get a "gantry" (or what I used to call an "A-frame") lifting device. They are now made in aluminum, and come apart for trailering in small box trailer. Use a pipe or steel I-beam as a spreader bar, lift the boat off the front of the trailer, and use a garage jack to jack up the rear of the keel. Once it's about 2 ft (600mm) off the concrete, pull the trailer out, put in some safety devices, and you can work on the centreboard. Mine had completely jammed up a couple of weeks ago, and as I hoped, it was the antifouling I painted the centreboard with, along with a bit of sand which jammed it. As you can see, I sanded back to epoxy, going through to 400 grit, then to be sure (to be sure) I silicon sprayed it completely (it won't last, but feels good). The centreboard now feels like it's floating, even out of the water. I'm looking forward to finally sailing Sandpiper with a full board down (it was sticky from the first sail), and hope I've finally got a weather helm! Final lesson - listen to what the designer says (don't paint the centreboard).........

Cheers,
Bob in Sydney

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[DanaDCole]

I assume you removed all the ballast first. I'm wondering also, depending on the capacity of the gantry, if you could have put the slings further back and lifted the whole boat. If so, it would still be prudent to put some safety stands in place before getting under it.

[herbt]

Jonlee, did you ever get that centerboard worked out and find the problem? Since I have not got to the point of installing mine maybe it is something I could avoid. If you mix graphite powder with the 2nd and 3rd coats of epoxy on things like the centerboard, and bottom and rudder below the water line and sand to 400 grit it make it all very slick and durable. Also no need to paint if you dont mind a black bottom.

Herb

[truenorth]

I gotta say the troubles identified here don't seem to be uncommon. There's not a lot of space between the cb and the cbt. Even a dry fit made me scratch my head. So if a little sand / gravel / gremlin gets in there, it's going to stick. I'm a little ways from launch, and was thinking about painting the cb. But given these issues, I'm not going to risk even those precious millimeters of paint.

[DanaDCole]

I have coated the inside of my trunk with graphite powder/epoxy, and plan to do the same with the centerboard. BTW, John Harris pointed out that he did not paint his cb and did not feel the need to because it will never be hit with direct sunlight.

[Bflat]

I doubt that Pocketship centerboards get stuck more than any other boat with a centerboard.

One drastic measure would be to replace the designed centerboard with a thinner one made of aluminum. Many boats have metal centerboards. They have issues too such as greater cost and metal might cause more wear to the slot (glad I did graphite powder in the slot). Such a change would also bring the center of gravity upward, I think - not a good thing.

Bruce Kirby's Norwalk Island Sharpies, for example, use plate aluminum for the centerboard, sliding within a fiber glassed plywood trunk.

The Melges scows use boards made of aluminum (6061 T6). My MC Scow has such boards about a 1/4 inch thick.

On the other hand, increasing the space would seem to just allow larger debris to get jammed, but I do suppose fishing it out would be a little easier. Either way I'd guess the hardest part of the freeing operation is getting under the boat no matter what the board thickness is.

As designed, it seems there would be nearly an 1/8 inch of clearance on each side of the board in the slot. That seems about right based on what I've observed on other boats. Assuming debris is probably stuck on only one side, the clearance would be nearly a 1/4 inch, enough to poke around with something like a metal yardstick or old saw blade.

My Pocketship is only about 20% done, so my comments are just conjecture.

Bob

[JonLee]

I still haven't had a chance to access my centerboard yet. I'll definitely post something when I do. Without knowing exactly what's causing the hang up, I'd tend to think more like bflat on this on...I don't see this as a result of any abnormality in the PocketShip design. All the clearances, etc. seem pretty normal. I'm guessing a bit a gunk just managed to work it's way up in there and cause a headache for me.