Centerboard Bashing

[NewbieDSer]

I recently purchased a used DS1 and am a newbie to boat ownership. I'm guessing it's a DS1 as it matches the online manuals I've found so far, but I've been unable to find a plate or anything with a boat number or anything other then the daysailer logo on the side. I'm lucky all rigging and woodwork is in great shape, but I'm concerned my CB may need some resuscitation.

When the CB is down it seems to be loose and swings with any side wake, especially at it's mooring. It seems to pendulum so hard i can see the trunk bulging and flexing with it. It's come to it that I'm afraid with enough of this it will eventually flex the trunk and rip itself out. With the CB up the trunk seems supported and that's how i leave it in mooring, but I've noticed it can happen while out on a sail as well. Is this normal, should i be concerned?

Thanks everyone!

[GreenLake]

Welcome to your DS.

With woodwork, it may well be a pre-1970 model and for those, the plaques are often lost.

If you have an idea of the 4 digit sail number (e.g. from sails originally purchased for or supplied with the boat, sometimes from registration papers) then it might be possible to date it a bit relative to other boats. Or you can check the DS1 design changes and see whether some of the small tweaks in the design allows you to bracket it.

Some lateral movement of the CB is indicated for a DS1, as is some bulging for the CB walls; but if either is excessive, it may indicate a problem. If you look around a bit in the forum, there's one recent thread in the Repair/Improvement section, where somebody found a CB with cracks around the plate into which the pivot pin from the CB handle is inserted. That poster also complained about a lot of banging and bulging.

Some owners have reinforced the CB trunk walls, others have narrowed the opening a bit, or both, in an attempt to better support the CB. A PO on my boat drilled a hole into the end of the pivot pin and tapped it for a bolt and then provided additional support on the other side:



The little raised bump may be original, if not, you'd have to glass over some kind of washer to allow a firm support on the port side.

Generally, on a mooring, you would raise the CB and not let it bang for days on end. If your CB doesn't stay up, you'll need to fix that, because leaving it down on a lively mooring will most certainly weaken the CB and or the trunk. Same reason you pull in the rudder.

If you do need to keep your boat out on the water, make sure you provide your phone number and/or contact details in case of problems. One guy I know just threw a clear plastic bottle into the cockpit with his name and phone number while anchoring unattended overnight. That came in handy when I saw his boat gently drift past my window out to sea on the tide. After I had caught and retrieved it, I found his info and was able to let him know.

[NewbieDSer]

Thanks Green Lake! Sail number is 2306 with molded seats, well, beige/white, and mast Jack (brass neck on threads?) and wood coamings. Comparing that to the Google doc seems reasonable to assume it's from the 60s. Luckily standing rigging is in great shape. Seems like someone glassed over an auto bailer or aft drain because it's now bail only.

There's likely some play in the cb handle as the cb sits about 6 inches below the boat, but it extends to full and does it's job on the water. It's moored for the season now, so barring any incidents with the CB I'll leave it in for the season and in the fall take it down and see if it can be optimized further. It seems to bang more on days when the wind is low and the boat is just rocking with the waves, but with a good wind it pulls it to attention and runs great. It's up when moored and holds great. Appreciate all your suggestions, very happy I found this very active group.

[GreenLake]

I dare say, you have narrowed it down. Enjoy your boat and we're here when you have questions.

[kokko]

The cb handle has a square section that fits in a square hole in the cb. This is often rounded allowing a lot of slop. Pull your back and inspect the hole, and fix with epoxy if necessary. Also, the cb is narrower than the slot on the trunk, so there can be a lot of clunking side to side. I bonded a couple of sections of polyethylene to the sides of the slot to reduce the slop. Maybe 3/8” x 2” x 16”. It shims the slot when the cb is down.

[Rush]

The cb handle has a square section that fits in a square hole in the cb. This is often rounded allowing a lot of slop. Pull your back and inspect the hole, and fix with epoxy if necessary. Also, the cb is narrower than the slot on the trunk, so there can be a lot of clunking side to side. I bonded a couple of sections of polyethylene to the sides of the slot to reduce the slop. Maybe 3/8” x 2” x 16”. It shims the slot when the cb is down.

I am working on a rebuild of my CB, which had reportedly taken a sandbar hit by the teenaged son of a previous owner. The metal plate insert in the CB was completely free-spinning inside and the four bolts that ran through The plate had sheared off. My guess is there is more to the sandbar story than the teenager confessed to. I’ll be installing the CB back in as soon as I and a very helpful and skilled neighbor can make the repair. (I bought the boat two weeks ago and the CB was not installed).

Where, exactly, did you install the polyethylene sheets? Maybe on the inside on the CB locker where the pivot point/handle is? The CB seems thickest so that seems likely.

If you added 2 thicknesses of 3/8” (3/4” overall), that’s a good bit of side to side play... I’m hoping that’s not the case with mine but want to be thinking that through. What is your source for the polyethylene sheets?

[GreenLake]

Polyethylene is the material for some of the cheap cutting boards. When I need a small quantity, I just head to the nearest store and look for a white, slightly translucent cutting board.

To stop a CB from banging you can mount strips of material on the board or on the inside walls of the trunk. Or both. I've seen pictures of people put material above the pin on the CB itself, or around the opening of the CB trunk (making it narrower).

One thing to watch out for is that polyethylene really doesn't bond well (it's chemically a relative of wax). I would be curious to learn how @kokko handled this issue. All I can think is that if you set it up with a bit of epoxy surrounding it, so it can't slide, then it might mostly suction that holds it in place, and with a CB pressing against it, that might work.

[Rush]

Thank you. I love to hear that I’m not the only one getting creative looking for materials. Interestingly, I’ve seen people melt down PE into blocks and cut and carve it like wood. If you were mounting a panel on the CB I wonder if you could use the CB itself as a mold for the hardening PE. Then the suction effect you are talking about would be maximized...

[kokko]

I used plastic trim lumber, which is pvc not polyethylene. Pvc bonds really well, so I used 3m 4200