CS15 #19 & luff pocket reefing idea/question

[niko]

Hi everybody!

I just received my plans for CS15 #19. I plan building her spring 2010. Or rather having her built. I personally don't have the time to do more than some planing and supporting work and therefor have to find a pro builder for the most of the work. Too bad, but still I'm so much looking forward seeing her grow and finally - hopefully - float.

Now to my idea and the question what do you think about it. (I'm afraid you gonna see more of that :-)

I plan to have the luff pocket version of the sails. I like the simplicity. Eliminating tracks and halyards is quite intriguing and I like the clean air foil I still know of my laser sailing days. The one big BUT that remains is reefing. As other have written, roller reefing around the mast pretty much destroys the windward ability of the rig. I'm definitely gonna have the third mast step (nice to have as an option). But going sailing on a windy day  I can imagine not wanting to miss the virtues of the cat ketch.

I think one could add a mast extension of about 3' or 3' 3'' to the bottom of the masts to achieve the final height. Now reefing would be done by removing the extension and zipping off the bottom part of the sail with a zipper.

Pros:

* The sail still would be a really clean air foil when reefed

* The masts would be shorter which would bring the weight down.

* Without the extension the masts would not be longer than the boat any more.

Cons:

* Can't reef on the water. We're on a lake here anyway. With some planing and caring for the weather forecast that's not a problem for us. Reefing with other systems (like restepping the mizzen) are best done in sheltered waters, too.

* More weight. But even when using twice the wall thickness it would add no more than about 2 (or at most 3) pounds to the overall weight of the mast. And these 2 pounds are located at the very bottom where they hurt the least.

* Must be strong enough. Laser masts are dividable so it should be possible to make the connection strong enough.

It's not a problem to get the right aluminium tubes with outer & inner diameters so that the extension could be made by gluing a 8'' or 10'' tube with 2.5'' inner diameter and 0.13'' wall thickness onto the bottom part. See attachement.

What do you think? Especially Graham?

[tom151]

If I were stuck on the sleeve luff (I'm not)...

I would use the standard masts and add a simple halyard - lowering the sail when the reef panel is removed

You probably have to add a second snotter bale at the reefed position of the sail and 2nd snotter line.

So when reefing you would (not me, because I know nothing of rigging a snotter)

1) ease the upper (not reefed) snotter line

2) ease off the halyard to the reef setting

3) slide the sail down the mast

( just writing this I can imagine that the sail might be able to be made with normal reef points not the zipper along the boom direction. You might just add a vertical seam in the sail at front of the mast from the tack up to the reef point -- held closed with a flat and commercial grade Velcro when not reefed. The Velcro WILL hold on a sail this small.)

4) tie in the reef point tack & clew and bundling lines along the bottom of the sail

5) tighten the second (reefing position snotter line)

Then your reef might work without the complication of removing sleeves while on the water.

Just my (longwinded) 2-cents,

[Peter HK]

If you're going to have a zip off section you can do it along the leech as I remember from sailboards many years ago. I seem to recall some zipped down the luff a few feet and then went to the clew effectively removing the leech batten area of the sail and leaving a scalloped leech. Might work for your purpose. Not sure how good the zip is for sail shape.

Peter HK

[niko]

Perhaps I should have specified better how I would place the zipper.  The zipper goes horizontally from the leech to the luff.  Luff pocket sails have broad gaps in the pocket where the snotter attaches.  I though about having a slit in the pocket - perhaps even overlapping - perhaps even with with velcro - where zipper meets the luff.

I can't imagine the zipper having more influence on sail shape than the sprit boom - which again doesn't seem to be as bad as most people anticipate.

All this is not about easy reefing on the water.  It's more about a simple setup with good airfoil and less lines.

[Ken_Potts]

  If you're looking for a good airfoil rather than reefing on the water go with the 3rd step.  My CS17 balances nicely sailing with the mizzen in the 3rd step and the main rolled up around the mast.

  Using the 3rd step to reef on the water in lots of wind is not impossible.  I've done it once while singlehanding.  I should repeat that I've done it (only) once in real weather.  Not fun, but possible.

  And storing the sails rolled up on the masts makes rigging quicker.

  If I were doing it all over, though, I think I might go with sail tracks and sails that reef individually.  I really do like the clean look and simplicity of the sleeve luffs, though.  Okay, I'm going to stop waffling now and shut up 

[niko]

I wanna store the sails wrapped around the mast and then lay the mast when storing the boat on the dock.  They have this nice floating dock/peer here.  All you have to do is pull up the boat about 1' onto the dock.  I just fear they don't dig the mast hanging over the boat 3' and the cover would go over the complete boat much better if the masts don't look out.

I'd have the third mast step anyway.  Not much work, more flexibility.