Reefing SunCat

[DanM]

We took our SunCat out on the lake for a few hours today. Winds about 12, but had been predicted to go higher. Just to be easy, and it was only our second sail of the season, we put in the reef. Comfortable sailing but the boat didn't seem to respond the same (no surprise). My ignorant question, which I only thought of in retrospect, is this: When you have that reef in, which I assume moves the center of effort aft, should you adjust the CB to compensate? How?

[bruce]

You don't say why the boat didn't feel right. I know I've said this before, but when I try to figure out trim issues, I like to review Bill Welch's book, the Competitive Cat.

With no headsail, when you reef the COE moves forward and down. If this caused significant increase in weather helm, then raising the CB to shift the lift further aft could help. But, this is secondary to heeling, crew-weight placement, and all the other things we have to balance.

In high winds, with the boat heeled over, the COE is way out to the side, and with the increased bow wave on the lee side, both contribute to cause substantial weather helm. The initial response is usually too much rudder, slowing the boat and decreasing control. Reefing gets the COE lower, reducing heeling. Flatter is better.

[Jim in TC]

When I picture the COE going forward, it makes me think of reducing weather helm...what am I missing here?

I haven't put a reef in on our Sun since sometime last season (in I am guessing ~15-18 MPH gusts the other day without much anxiety) but my recollection is that we were pulled to weather quite a bit less. My recollection could, admittedly, be quite far off.

[bruce]

I was looking at the drive component of the COE, that allows the boat to sail to weather, and the not the heel component. Move that further forward, vs. the offsetting moment of the CB lift, i.e. the lead, and I see a slight addition to weather helm. I doubt I would notice it. Dan was asking how he might adjust the CB to balance, so I focused on that. If he was feeling additional lee helm, he could lower the board.

With heeling, weight distribution, sail shape, wind speed, sea state, and other factors considered, I don't think the exact setting of the CB will be all that critical. Upwind the board is down, on the beam the board is in the middle, and down wind the board is up, but it's not that fussy for us. Weight distribution fore and aft, and side to side, is much more important on our boat.

[DanM]

Thanks, lots to think about. Two takeaways for me (an intermediate level sailor at best):  pay more attention to adjusting crew weight, and go back and re-read "The Competitive Cat". A fine book that I haven't cracked in a few years.
   I know the old saw that you reef when it first crosses your mind. But perhaps reefing too early in an attempt to have a leisurely afternoon sail (in this case winds around 12 predicted to build to 15) leaves the boat underpowered and therefore harder to tack and less capable of maneuvering overall. Especially with the SunCat, which is a bit under canvassed anyway. I never gave much thought to the possible downside of reefing early. Thoughts?
  Frankly, I suspect another part of my problem was the beginnings of heat exhaustion, which just knocked me down the moment we got back on the mooring ball. Another lesson: take it seriously when you see the "heat advisory" message on the NOAA weather site. And yes, we were drinking tons of water.

[bruce]

I agree Dan, we've got oppressive heat right now and we're not sailing until it breaks, or at least moderates some. If it had been a more comfortable day, you could have shaken out the reef and compared.

We're under canvassed as well, we like to see about 6 kts of wind minimum, although the boat does ghost around nicely in mill-pond conditions. Chop is more limiting for us. We rarely reef before we get out there, and will tuck behind a windward shore to get out of the fetch to reef, if possible. I don't recall a time that we've reefed too early, but I certainly understand the motivation to do so. My crew doesn't like sporty conditions.

I will say, that if tacking was a problem, that the CB could be critical. The only times I have trouble tacking is when the motor is dragging, or I've got too little board down and the boat slips sideways in a turn. Definitely try more board down then, it might be the same for a SC.

[Jim in TC]

I am more willing than the first mate to set out in "sporty" conditions (we have a neighbor who likes to crew at those times) and also willing to tackle some building wind at full sail. Keep in mind the Sun is a forgiving craft. But I also prefer to shake out a reef set in at the slip in an over-abundance of caution than to put one in under serious wind and wave action out on the bay. Admittedly some conflicting attitudes and opportunities for failures of judgement built into those statements.

We sometimes have some difficulty coming about, usually in light air with too little headway to make it easily and fully about. In those light airs there is also a tendency, once she manages the new tack, to continue to fall off until we can regain rudder control (enough way on for the rudder to respond). Sheeting out more than I "normally" would tends to alleviate this.

During our heat wave we were fortunate to (usually) have nice (and a couple times considerable) breezes out of the north providing good cooling. We do have a bimini that provided protection on a couple of nearly still, overly hot sails.

The Suns have a well deserved reputation for a strong weather helm, which can be reduced by tinkering with the centerboard (ours is actually only rarely fully down).

Bruce's point about ghosting around in light air may not be quite as true of the Sun as the Picnic (I have never been in a position to compare) but still it takes but a whisper to move them along. It is the "light and variable" wind that can be the most vexing.

[DanM]

Jim, yes, I know this feeling you mention:

" In those light airs there is also a tendency, once she manages the new tack, to continue to fall off until we can regain rudder control (enough way on for the rudder to respond). Sheeting out more than I "normally" would tends to alleviate this."

  I usually deal with this by saying encouraging words to the boat.. "Come on baby...stop swinging...... let's get moving....point it on up.....that's a good girl....."

How the pros do it.

[Jim in TC]

  I usually deal with this by saying encouraging words to the boat.. "Come on baby...stop swinging...... let's get moving....point it on up.....that's a good girl....."

How the pros do it.

Oh, I see now. And I mistakenly thought this was an occasion for 'cursing like a sailor.'

[mikehennessy]

Greetings folks!

So for those who do not know, I have had my Sunday Cat since March 2019 and have just adjusted to the intricacies. 

For the prior decade racing included the Thistle (17") and Flying Scot (19"):  one needs to keep the boat flat.  Under 5 degrees of heal.  Crew placement is critical for this.  If your tiller isn't straight, you have the brake on. 

When a puff hits, I head up and the boat levels out smoothly.  This is especially easy as you watch the wind moving down the water.  Head up just before the puff hits and she will flatten.

I have practices reefing but have not felt the need to in under 20 knot winds.  Keep her flat and easy main if you need.  I chicken gybe if I have non-sailor guests.

Regards,
Mike

[bruce]

Thanks Mike.

In really light conditions, say 4-7 kts, enough to move the boat but not fast, I find that inducing a few degrees of leeward heel helps to keep the sail filled.

[mikehennessy]

I concur!

[Jim in TC]

...and anyway, I kinda like running fast, close hauled and well heeled (though the first mate does not concur, preferring a modest wind and a nice flat beam reach).