Thursday, July 16, 2015

Skiffing it again

So now that I have one less boat to focus on, I not only feel a bit relieved, but also a bit invigorated to use the boats I have.  The Bristol is still not an option for sailing, but I can continue working on her interior.  I love being in her cabin so doing this work is a pleasure.
Skiff with Current rig.
The only other sailing boat I have is the skiff.  The reduction of the sail area was a good thing.  The spars are smaller and easier to deal with, and the boat can be out in stronger wind.  On the negative side, the new sail plan seems to have moved the center of effort forward enough so that she really doesn't sail to windward.  Previously I was able to move myself forward and get the resistance underwater forward so she would just make to windward.  I was able to get away without a foil (daggerboard, swing keel or lee board), but now the sails center of effort combined with the reduced area, seem to mean that I can't get the underbody center of effort far enough forward and there is not enough drive from the sail to get her to overcome making leeway.  Or so I am assessing the situation.

I have 2 possibilities, I believe, for remedy. 1) build a trunk and dagger board and install it  2) add a mizzen sail.
The daggerboard option is pretty obvious, but there are drawbacks to it.  First is that the keel on the boat is only 1-1/2 inches wide so the trunk would have to be constructed in a way to compensate for the loss of keel structure.  I have an idea how this could be done, but it does mean cutting a hole in the bottom of the skiff.  It also means loosing the space that right now is pretty comfortable, and this boat has minimal beam so loosing any space is not the most wonderful thing.

The idea for adding a mizzen is that not only would it shift the center of effort aft, where there is more underbody,  but it would add sail area, that was lost, but down low, where it wouldn't cause as much heal in a skinny boat.  I also think that a mizzen might make the boat capable of steering herself, or at least using the trim of the mizzen to balance her out.  On the negative side the mizzen would be one more spar to deal with, two actually counting the boom or yard and it would mean retrofitting a mast step in the after deck.  It would do nothing to improve the resistance to leeway for the underbody, but I think I might be able to gain back the ability to sail just to windward.

A mizzen would be a sharpie sprit sail, with a sprit yard that is parallel to  the waterline, and a sheet lead to the transom.  A standard boom and right angle at the foot and luff would also work.  The mizzen mast could also give a better lead for the mainsheet. Bonus.

mocked up ketch rig w/jib
Well, suddenly it's a lot of sail area.  The thing about adding the mizzen is that it can easily be not used if it proves to be a bad choice, and with out any real alterations to the hull.  If it does work but the boat seems to really want the centerboard still, I can always add it later.  The centerboard might also add some counter resistance to the sails.

The mizzen mast would make a cockpit tent rig very easy, just a line between the masts and a tarp.  Sailing with jib and mizzen only might be an interesting option too.

This boat is really too skinning to be a good choice for sailing.  But, it is what I have right now.  I can still row it and sail it while building the mizzen and sewing the sail.  I would really like a beamier boat for sailing but I would like to enjoy not having so many boats for a while.  I think that this winter I may take on building a real sailing boat in the under 15 foot range.  For now I will just try this and see how it goes.

It is all just messing about.

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