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Let's Talk Centerboard operation.

PostPosted: Thu Aug 13, 2015 8:31 am
by Rakozy
I recently purchased a DS II and sailed it a few times, but I'm unclear on the proper operation of the keel.

1. OK, the boat is pointed into the wind at the dock. The sail and jib raised. When is the appropriate time to lower the keel when departing the dock?

2. Do I leave the keel fully extended (down) in all sailing conditions?

3. * When released, will the keel remain fully extended "down" on its own because of it's weight? Or do I have to hold it in the down position by wrapping the keel-line around the cleat to hold it in the down position?

4. * When returning to the boat launch under sail, WHEN should I raise the keel and still have good control over the boat?

Any other suggestions would be appreciated. 8)

Re: Let's Talk KEEL operation.

PostPosted: Thu Aug 13, 2015 9:17 am
by Baysailer
Rakozy, All good questions, a centerboard works a little different from a keel but with the same purpose. Both offer underwater resistance to the pressures on the sails above the water. A keel is weighted but a daysailer centerboard's weight plays little role in righting a boat. Without the centerboard down the daysailer will slip with the wind. The advantage to a centerboard is you can raise and lower it to change the balance.

1. If the waters deep enough and there's no underwater obstructions you can fully lower the centerboard and rudder before you leave the dock. If water depth is questionable lower the centerboard about halfway so you have some control. Lower the rudder all the way if at all possible from the start.

2. For the most part you can sail with the centerboard full down for all conditions. You may want to experiment with pulling it up a little for downwind and to see how it affects helm balance. A little time in medium condition testing and you'll see the value of a movable board.

3. I don't know about DS II's but if the cleat is released the board will raise some on its own due to forces on the front of the board.

4. Returning to the dock I'd have the board down as much as possible for as late as you can. Around the docks are tight with other boats around and the winds often get goofy too so you want as much control as you can get.

Fred

Re: Let's Talk KEEL operation.

PostPosted: Thu Aug 13, 2015 9:21 am
by Rakozy
Fred,

Good information that I will put to use.

Thanks!

Re: Let's Talk Centerboard operation.

PostPosted: Thu Aug 13, 2015 3:07 pm
by GreenLake
I've edited the thread title, so people looking for CB information can find it.

Re: Let's Talk KEEL operation.

PostPosted: Thu Aug 13, 2015 3:11 pm
by jeadstx
With the DS II, the centerboard control line is continuous (unless modified by a previous owner). As Baysailer said, lower the centerboard before starting to sail otherwise you will find that the boat will side slip and have trouble holding a heading.

I rarely sail with the board down 100%. The most I ever have it down is about 7/8 the way. The centerboard on a Day Sailer weighs about 21 pounds as I recall. When sailing straight downwind you can raise the board almost all the way up to reduce drag and go a little faster, but get it back down before changing direction as it is easier than with water pressure on it. When the board is down, you have to cleat the line to keep the board in position. If you should bump an obstruction, pull the board up. The rudder will kick up if it hits an obstruction. Some sailors have replaced the horn cleat with an auto release cleat.

John

Re: Let's Talk Centerboard operation.

PostPosted: Thu Aug 13, 2015 3:19 pm
by GreenLake
When not going upwind and in high winds it pays to raise the CB partially or fully:

First, it cuts drag doing so, and that's always nice. Least drag with it all the way up.

Second, it removes a "tripping" hazard, that is, if a gust hits, the boat can respond by sliding to leeward instead of heeling (and possibly capsizing).

Third, it's essentially unnecessary when going downwind, as with the wind from behind there's normally nothing that would push the boat sideways, so there's nothing for the CB to resist.

When not sailing with the jib, raising the CB partially will help balance the boat (because the CB folds backwards, a partially "raised" CB is also further aft).

Fully agree with all the other points mentioned by Fred.

The CB for the DS may be undersized a bit, so I wonder about John's not lowering his fully. Other than that I agree with his observations.

Re: Let's Talk Centerboard operation.

PostPosted: Thu Aug 13, 2015 4:07 pm
by jeadstx
On my boat, I have encountered more jams when I keep it down full over a period of time while sailing. I put it down full, then bring it up just a bit.

John

Re: Let's Talk Centerboard operation.

PostPosted: Thu Aug 13, 2015 8:59 pm
by TIM WEBB
The first time I "lowered" the CB with the boat careened, I was quite surprised to find that at full down, i.e. downhaul pulled as tight as possible, the CB actually goes past full vertical and "hyperextends" (correct term?) even more forward. This could in some cases be good with the rudder, but w/ the CB I can't think of any, so when I want the board fully down (close hauled), I lower it all the way, then raise it back up about 10% before cleating off the auto release DH cleat. Close and beam reach I'll bring it up halfway, and for anthing beyond that it's pretty much up all the way.

Re: Let's Talk Centerboard operation.

PostPosted: Fri Aug 14, 2015 1:41 am
by GreenLake
Ah, so this 100% doesn't represent 90 degrees, but some 100% of the distance you can pull the downhaul. (I'm thinking too much of a DS1, where the angle of the lever tells you precisely what the board is doing).

Re: Let's Talk Centerboard operation.

PostPosted: Fri Aug 14, 2015 8:12 pm
by TIM WEBB
Correct: on TRW, full DH puts the CB past 90 degrees. Don't know if all DS2's are this way. Does the DS1 lever actually correspond to the angle of the board, i.e. board all the way up, lever points straight up, board at 90 degrees (down), lever points straight back?

On a DS2, a quick glance at the UH tackle on the cuddy floor between the bulkhead and the mast step tells one exactly where the board is ... ;-P

Re: Let's Talk Centerboard operation.

PostPosted: Fri Aug 14, 2015 10:10 pm
by GreenLake
TIM WEBB wrote: Does the DS1 lever actually correspond to the angle of the board, i.e. board all the way up, lever points straight up, board at 90 degrees (down), lever points straight back?


Well, the most important thing is that the movement of the handle is 1:1 with the board. So even if the sector isn't alligned with the vertical, you still know when you've moved the handle through 90 degrees. (Caveat: if the square hole is worn, all bets are off, bit it's easy to shim).

Re: Let's Talk Centerboard operation.

PostPosted: Thu Aug 20, 2015 11:30 am
by Rakozy
Centerboard Cleat:
Could I replace the 3.5" cleat with a clam-cleat? It would be much easier to use?

Bill

Re: Let's Talk Centerboard operation.

PostPosted: Thu Aug 20, 2015 1:25 pm
by GreenLake
I would think that any cleat will do, but let's hear from the DSII owners on this.

Re: Let's Talk Centerboard operation.

PostPosted: Thu Aug 20, 2015 4:08 pm
by MookaCB
Rakozy wrote:Centerboard Cleat:
Could I replace the 3.5" cleat with a clam-cleat? It would be much easier to use?

Bill


I just picked up a auto-release cam cleat to replace the horn cleat. They are designed to hold down kick-up rudders and release if you hit something. I haven't installed it yet, but I think it will still hold the board down and keep the wires from getting jammed while also allowing the board to lift if I hit bottom.

http://www.westmarine.com/buy/clamcleat ... t--1158443

Re: Let's Talk Centerboard operation.

PostPosted: Thu Aug 20, 2015 6:13 pm
by jeadstx
There have been others that have replaced the horn cleat with an auto release cam cleat. I have been thinking about doing it also.

John