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Catalina/Capri 25/250 Sailor's Forums

Catalina 25 Specific Forum

Main sail trim

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TRogers
1st Mate

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USA
90 Posts

Initially Posted - 09/11/2006 : 15:00:12

After a particularly unsucessful summer of trying racing for the first time, I found a book at Barnes and Noble that was specifically about racing.

From it, I concluded that I had a few misconceptions about sail trim. I've corrected putting my jib blocks way to far foreward for light winds (or any level of wind).

However, I found one particular item that puzzles me as it seems almost impossible to do (at least with my old sail).

While beating to windward, the book suggests that use of the traveller is to be able to center the boom without having too much downward pressure on it as opposed to trying to get it to cross slightly over to the windward side of the boat which I've been doing. I can accept that.

The next suggestion is that the top batten should be more or less parallel to the boom when viewed from underneath the boom which I am guessing is some sort of indication of the amount of twist. When I first checked this I found that it wasn't even close (45 degree angle?). The only way I could get it even close to parallel was to pull on the reefing line at the leech which flattened out the sail considerably at the head but made it kind of deformed at the foot. I got the impression that I was getting better performance, but I'm not entirely sure.

I believe my sail is oroginal equipment on a 1981 model, so I could believe that my sail is stretched out and makes it hard to achieve what the book suggests.

Thoughts?

Tom Rogers
Tack n Two
Spokane, WA

Edited by - on

ClamBeach
Master Marine Consultant

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3072 Posts

Response Posted - 09/11/2006 : 19:44:53

>"...believe that my sail is stretched out and makes it hard to achieve what the book suggests."

I think you've hit the proverbial nail on the head. A stretched out sail can get you from point A to point B, but it can't be brought into optimum trim.

If you're gonna race (and be competitive) you need good, fresh sails. No way around it.

Edited by - on

pegasus
1st Mate

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USA
65 Posts

Response Posted - 09/12/2006 : 07:17:06

Before you buy a new sail, I'd ask a local 'expert' to take a look at your rig. I had similar concerns about the main on my '86 TR FK and asked a local sail maker (Whom I thought certainly would press me to buy a new suit of sails) Instead, he showed me what was wrong with how the sail was rigged and the corrections made a world of difference. The sails are 20 years old, but weren't sailed that much as the previous owners were casual cruisers. Racing is tough on sails.

Having said that, I wholeheartedly agree with ClamBeach - winning in racing requires good sails. But the best sails won't win races if you're experience level is low relative to your competition. I bought a Catalina-22 about 8 years ago and raced as much as I could (with family, work, beer drinking and other important obligations taking precedent over sailing). I finished dead last for about two summers. Then, as I learned about racing techniques, and how to trim and sail the boat, I started to move up in the pack. Crewing is an excellent learning opportunity, but expereince is the best teacher.

p.s. do you have a boom vang?

Edited by - on

bmelchionda
1st Mate

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63 Posts

Response Posted - 09/12/2006 : 08:34:16

I have the same issue on my 1986 Catalina 25 TR (what is a "FK" pegasus?) Also, I do have a boom vang, but even tight, I still have the issue as originally described.
Best,
Bryan

Edited by - on

aeckhart
Master Marine Consultant

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USA
1709 Posts

Response Posted - 09/12/2006 : 08:37:37

There are several "devices" for mainsail trim, some of which were either not offered as standard equipment or were optional on the C25. These include an outhaul with mechanical advantage, which is very useful if you have a loose-footed main. A boom vang - I prefer a rigid vang, is another which could have helped your situation. A decent main sheet traveler with adequate length across the width of the boat. A cunningham for use in heavy air. An adjustable backstay for mast bend/head stay tension. All of these work in concert to properly trim the main. I have and use all but the adjustable backstay. If you are serious about sail trim, but wnat to keep costs down, put them on your boat first. If you're really serious about racing, then buy new sails once you've learned to use the new equipment.

To give you an idea, the three top boats in the nationals this year had either a main, a genoa, or both made from non-dacron material. The overall winner had sails made from material other than dacron. These are serious racers.

Edited by - aeckhart on 09/12/2006 08:39:22

TRogers
1st Mate

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USA
90 Posts

Response Posted - 09/12/2006 : 18:50:40

I do have the outhaul, boom vang, adjustable back stay, cunningham all present on the boat at this time. Almost more complicated than I can understand at this time, but I'm getting there slowly.

The thing I'm most curious about is the business about having the top batten and the boom parallel when sighted from below. As I mentioned, I could get somewhere in the vicinity of this but end up deforming the bottom of the sail the way I do it.

Seems to me that managing to get the batten alignment with the boom would leave the entire sail extremely flat (at least compared to what my old sail shows). Of course, that may be the expectation. I really don't have a point of comparison to work from.

Do you serious racers out there end up manage to get the top batten lined up as suggested?

Edited by - on

Frank Hopper
Past Commodore

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Pitcairn Island
6776 Posts

Response Posted - 09/12/2006 : 19:28:26

Rarely, Don't expect our rigs to act like racing rigs. I think it is more important to judge your mainsail twist against your headsail twist If they are the same you have an excellent slot and good acceleration of the air across your main.

Edited by - on

Ericson33
Admiral

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USA
892 Posts

Response Posted - 09/13/2006 : 01:22:54

I know I don't own a Catalina 25, but I would like to give a little advise to the subject on hand. There are several things to keep in mind about main sail trim, and setting the top batten parallel to the boom is the correct sail shape for pointing to weather. Frank mentioned the slot between the Genoa and the main sail and this is very important because the head sail on the 25 is really what gives the boat the driving force it has. Keeping the slot open and not back winding the main is the key, well having all of the tell tails flying even is the key but we will get to that here in a little bit.

First lets get to the main sail trim. When going to weather or after a tack you really want to have the sail as full as possible. You also don't want to be pinching at this point but bear off a couple of degrees so the boat can get up on its feet then trim the main and genoa in for pointing mode.

After the tack take the main sail and the genoa sheets in about 90 % this will keep the sails full and the draft around the 45 to 50% mark. After the boat starts getting back to hull speed then its time to trim the sails to the correct draft. The top telltale on the main should be flying about 60% of the time with all of the others flying strait.

Pointing mode- With the boat going to weather almost at hull speed its time to get some better shape in the main sail, this means making the main sail flatter so that the wind hits the sail at the luff and the draft in the sail is around 35 to 40 percent off of the luff and its flowing strait back off of the luff causing lift. Tighten up the main sheet now until the boom is in the center of the boat, and the top batten is parallel to the boom. you should be able to do this by moving the traveler to the weather side of the boat and then sheeting in the main hard. You also should get the top batten to twist to the weather side if you sheet in tight enough. I think that using the traveler here is the key. I am betting that this is what is going wrong with the main sail.

Boom vang Sheeting- You can also start using the boom vang in the puffs to control the boom from raising up and causing the sail to become de-powered to help the boat from healing over.

Outhaul- The outhaul is there to flatten the foot of the sail when the breeze comes up. Most systems just plain suck so most of us tend to set the outhaul when head to wind, then release it when going downwind, and reset it before the leeward mark.

Cunningham and Main Halyard. the halyard is really for you to be able to raise the sail and to control the shape of the luff. We have three marks on our halyard, One for light air, One for medium air and one for heavy air. The we use the Cunningham to fine tune the luff. In light air you will want the sail to just be tight enough on the luff to take the ripples out. We adjust tighter from there with more wind speed.

Most people tend to do the SET and FORGET, and this is not the case for true speed upwind. You really need to play the sails to allow for the puffs and try and keep the boat flat as possible. remember that you are creating a foil for the air to flow over, not for the sail to capture the air, Except for downwind sailing.

Genoa - Now that you have control over the main sail the same goes for the genoa. There can be the same controls set up for the forsail, but most people just have the genoa sheets, and the cars. So I will just go into these.

Car placement- The cars should be placed on the track so when you start to go head to wind and the forsail luffs you want the telltales all to break at the same time. This will tell you that you have the wind flowing correctly on both sides of the sail and that the lift is right. Sheeting the genoa in on a tack should be the same as the main sail sheet 90% then when upto speed tighten the sheet up for speed.

I have never seen the setup sheet for the Catalina 25 but the sail size is close to ours so I would say that you would want the foot of the genoa 2" to 4" off of the bottom shroud base and almost touching the spreader tip in 12 to 15 knots.
In lighter air I would say that the foot needs to be 6 to 8 inches off of the shroud and 4 inches off of the spreader.

Go out with the boat and have fun keep your eyes on the sails and play around with the adjustments. You will find a good combination that will work for you, and the boat should sail to its numbers.
I hope this helps you out.

Edited by - Ericson33 on 09/13/2006 01:24:59

aeckhart
Master Marine Consultant

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USA
1709 Posts

Response Posted - 09/13/2006 : 07:58:28

I think Chris hit the mark and possibly explains why many feel the Catalina 25 wing keel is a poor upwind sailer. Some days my wing keel tall rig goes like heck upwind and other days it doesn't. I suspect that on the days it doesn't I'm just not doing the things I need to do regarding sail shape. Granted the C25 wing has it's upwind problems but I suspect that for many of us it's a case of having the right controls on board, how to use them, and, as in my case, a desire to put max committment into every race. Although I like to tweek my rig and sail fast, I also enjoy sailing too much to be overly concerned with sail shape, and therefore winning or losing. I'm too old and the stress would probably kill me.

Edited by - on

TRogers
1st Mate

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USA
90 Posts

Response Posted - 09/13/2006 : 12:18:57

Fhopper,

Thanks for that picture!

I think it really proves to me how stretched out my main is (or at least something else isn't quite right). I can't get it anywhere close to that flat. I've got a big bag at the bottom. At least I know now that it is possible to get that shape.

My first suspect is that my topping lift is a little high. I'll try lengthening the topping lift a little first and see what happens.

Edited by - on

dlucier
Master Marine Consultant

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Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 09/13/2006 : 12:37:27

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by TRogers
 I think it really proves to me how stretched out my main is (or at least something else isn't quite right). I can't get it anywhere close to that flat. I've got a big bag at the bottom. At least I know now that it is possible to get that shape.<hr height="1" noshade id="quote"></blockquote id="quote">

Tom,

That bag at the bottom of your main could be a shelf foot. The shelf foot on my old main looked baggy enough to be used for a hammock.

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by TRogers
 My first suspect is that my topping lift is a little high. I'll try lengthening the topping lift a little first and see what happens.
<hr height="1" noshade id="quote"></blockquote id="quote">

Although one might use the topping lift to take the weight of the boom off of the main in light air, in general the topping lift should be slackened when the main is up.

Edited by - dlucier on 09/13/2006 12:47:48

Champipple
Master Marine Consultant

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USA
6855 Posts

Response Posted - 09/13/2006 : 15:07:49

Everybody pretty much hit on all of the sail controls so without being redundant let me throw this into the fray.

Our traveler stinks… it travels about as much as Michael Jordan gets called for traveling. The “groove” on our sail and probably most of the C25s upwind is going to put the car well past center. To Bring in that batten you will probably need a bit of vang and some main sheet too. Possibly some leech tension. Definitely not reefing line

Bringing your Jib in to about 3 inches off the shrouds sounds great, but not all of our boats (actually very few) have inboard jib tracks.

New sails will make a big difference, if you are pretty sure that your stuff is original, then unless all of the previous owners left them in their climate controlled attic and used the boat as a power boat, they are toast. I don’t care how well you take care of sails, if they are 20 years old they stink.

Keep your bottom Clean.

Read Bill Gladstone’s Sail Trim Book – its carried by North Sails and is by far one of the easiest reads on Sail Trim out there….

There are a number of theories on the slot and matching sails, twist, depth etc. The one thing I’ve found is they are all good theories and they usually all work on at least one boat. Regardless of what you read here, in a book, or hear in a seminar or on TV the only way it is going to truly sink in is if you get out there and fart around with it.

Gladstone’s book has some great techniques for logging what you did relative to the conditions. I would recommend spending some time doing that, getting the experience and experimenting.

The suggestion to talk to a sailmaker is great advice as well. Get one to sail with you – it is getting into their slow season right now so it is a good time to place the call.

dw

Edited by - on

Frank Hopper
Past Commodore

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Pitcairn Island
6776 Posts

Response Posted - 09/13/2006 : 15:16:23

Duane... and my sails look...

(like I am close hauled and sailing way under my course!)

Edited by - on

Champipple
Master Marine Consultant

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USA
6855 Posts

Response Posted - 09/13/2006 : 21:44:44

Missed something there Frank....

Edited by - on

86Cat25
Deckhand

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USA
22 Posts

Response Posted - 09/14/2006 : 10:35:09

I have learned a lot about how to trim my main on this thread. That has raised questions about the cunningham. Is is needed? Couldnt you achieve the same thing by tightening or loosening the halyard? Maybe im not seeing the real point of this equipment?

Edited by - on

Frank Hopper
Past Commodore

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Pitcairn Island
6776 Posts

Response Posted - 09/14/2006 : 10:57:57

I think the Cunningham was developed with a fixed gooseneck in mind. If your sail if fully hauled and you need more luff tension then the Cunningham is the ticket, but I bet a purchase on a sliding gooseneck could do the same thing. If your sail is old then the Cunningham will probably help you more. I finally rigged mine last weekend because I was tired of seeing it lying around the boat. On my boat I tend to reef early rather than use a Cunningham to stay on my feet, but that is because I reef before I reduce headsail.

Edited by - on

TRogers
1st Mate

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USA
90 Posts

Response Posted - 09/17/2006 : 21:41:03

Thanks for everyone's input.

I increased the length of the topping lift today and got a much better sail shape. Not perfect, but much improved. Seem to be able to point a little higher, plus its much easier to flake and tied down the sail when single handed!

Edited by - on

djn
Master Marine Consultant

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USA
1561 Posts

Response Posted - 09/17/2006 : 21:58:51

Hi Tom, I am just guessing here, but are you using the topping lift while sailing? It can be used in light air to lift up and give more bag, but you do not sail with it. Cheers.

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jerlim
Master Marine Consultant

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USA
1484 Posts

Response Posted - 09/18/2006 : 10:05:30

oh...oh - I think I'm going to embarrass myself... am I to understand that you should not sail w/ the topping lift connected? Being a newbie, being dopey and maybe overly cautious… I’ve trimmed the topping lift to keep the boom just above my head height while standing…
Jerry

Edited by - on

Frank Hopper
Past Commodore

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Pitcairn Island
6776 Posts

Response Posted - 09/18/2006 : 10:54:33

huge error, your sail has never been correct. toppping lift must be allowed to be slack under all conditions unless you are intentionally using it to billow the sail in light air. You are about to discover a new boat.

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djn
Master Marine Consultant

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USA
1561 Posts

Response Posted - 09/18/2006 : 11:21:47

Not a big problem Jerry. I/ve done that before and didn't sink!!! As Frank said, you are about to discover a new boat. Let us know the differences you experience. Cheers.

Edited by - on

jerlim
Master Marine Consultant

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USA
1484 Posts

Response Posted - 09/18/2006 : 14:48:35

Thanks for the encouragement - what differences can expect?
Jerry

Edited by - on

TRogers
1st Mate

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USA
90 Posts

Response Posted - 09/18/2006 : 15:41:56

"Hi Tom, I am just guessing here, but are you using the topping lift while sailing? It can be used in light air to lift up and give more bag, but you do not sail with it. Cheers"

Actually, I think I replaced the topping lift line late last year and the replacement was not long enough. Therefore, even though the topping lift was at maximum extension, the boom was still too high.

A lesson learned.

Edited by - on

djn
Master Marine Consultant

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USA
1561 Posts

Response Posted - 09/18/2006 : 16:11:44

Hi Tom, are you talking about the boom being too high while you are sailing? Cheers.

Edited by - on

Gambit
Navigator

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USA
160 Posts

Response Posted - 09/18/2006 : 16:17:10

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by TRogers
 
While beating to windward, the book suggests that use of the traveller is to be able to center the boom without having too much downward pressure on it as opposed to trying to get it to cross slightly over to the windward side of the boat which I've been doing. I can accept that.
<hr height="1" noshade id="quote"></blockquote id="quote">

Great thread, thanks for starting the discussion. With regards to the traveler keeping the boom centered, I notice that when my traveler is up and the boom in windward of center we seem to point a bit better. We may be taking a speed hit on this though. Does that sound right? The extra degree or two may be worth it if pinching for a mark, speed hit vs. two additional tacks. This must also do bad things for the slot since the headsail not be on a similar angle.

My traveler is not the stock one, we have it mounted across the forward part of the cockpit just outside the main hatch.

Thanks,

Edited by - on

Steve Milby
Past Commodore

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USA
5902 Posts

Response Posted - 09/18/2006 : 17:06:35

<blockquote id="quote">quote:<hr height="1" noshade id="quote">The extra degree or two may be worth it if pinching for a mark, speed hit vs. two additional tacks. <hr height="1" noshade id="quote"></blockquote id="quote"> If you tack short of the layline, pinching actually reduces the likelihood that you'll be able to make it around the mark. It kills your boatspeed and a boat that is going slower can't point as high as a boat that's going faster. You'll rarely make it around the mark by pinching. The better choice is to maximize your speed by bearing off the wind a couple more degrees. When you get as close to the mark as possible, steer the boat straight up to windward and ease the sheets completely. The boat can often coast as much as a boat length to windward. Then, when you think you can round the mark, bear off, trim your sails and get them drawing again, and sail around the mark. It's called "shooting the mark."

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