Tell me how to improve (pic included)

Joe · Mar 12, 2012

did you try adjusting the leech line? that's the small cord sewn in to the leech, there should be a small cleat or button to hold it in postion. Basically, it takes up the stretch in the leech that a sail develops as it ages. Avoid over tensioning this line or you will cup the leech and drastically affect performance.

Ken Prichard · Mar 13, 2012

I doubt a 1.5' traveler will accomplish much.
A stronger vang won't provide more vang. It will just make applying it easier.
I think you are correct in your analysis of too much twist. If having your main and vang on full will not solve the problem then I would talk to your sail loft. They may be able to do an adjustment. Worst case you're looking at a new sail.
BTW - The draft position in that sail is way too far aft. That's only solved by luff tension so there's not much you can do about that if your halyard is fully tensioned and no cunningham.

Merlin Clark · Mar 13, 2012

If you don't have a traveler how is your boat rigged?
The position of the traveler track on my boat made for tight quarters and skinned shins and I wanted to add a bimini that is well under standing room so I got rid of the traveler. The track was only 3' and end boom so while better than a Crosby rig or fixed point it was no where near as important to me as shade down here in brain pan frying country.
I went with a double mainsheet and it works great, I have a little better control than I did with the traveler as I can sheet higher with the double. I went with 3:1 on each side and it's not bad at all even at 20+ kts. The first pic is of the rig when I first installed it and the second is underway and before I added the bimini.
I still need to add a vang.

Ken Prichard · Mar 13, 2012

To see options for rigging a cunningham look at page 21 of Harken's catalog. I'm sure you can find it online through Google.

justsomeguy · Mar 13, 2012

If that picture of your mainsail shows what you call a "close reach", why am I seeing the port shrouds against the mainsail? Unless they're really swept back, of course, because there's no backstay. Not being familiar with your boat, I guess I'd haul in on the mainsheet some more? JMO

justsomeguy · Mar 13, 2012

Sublime said:
It's a B&R rig so they're swept back.

When I would haul in on the mainsheet, the trim on the lower portion of the sail wouldn't be right and needed to be let out.

Maybe the sail is older, but if you can balance the effect, then try a little leach tightening?

cwkemp · Mar 13, 2012

I cant see telltales on the leach but it looks like the top of the sail may be over trimmed (too little twist) and flapping might occur at the head, but telltales would definitely help

RichH · Mar 13, 2012

Sublime ----

the 'scallops' along the leech ... and if you carefully look along the luff you will also see these 'scallops' which indicates that the sail isnt properly raised to it 'designed' length. Here's how to properly raise a dacron mainsail: http://forums.sbo.sailboatowners.com/showthread.php?t=120970
Those small horizontal 'girts' or small creases emanating from the attachment slugs at the luff tend to indicate that youve not been raising this sail correctly for perhaps a long time.

Properly raising will also reduce the 'over draft' or 'too much draft' and will help correct the 'reaching problem' in your other "B&R" post and will allow the sail/boom to be eased out even more and without as much sail-chafing-on the shrouds as you show in the pic in that other post ... and in which shows the sail could use a bit more outhaul tension to further reduce draft, etc.

If you dont have it already, Id kindly suggest starting with Don Guillete's "Sail Trim User's Guide", etc. (from the 'bookstore' here on SBO) ... but try the 'how to raise', first. Then secondly, get some 'tell-tales' on your sails, as its next to IMPOSSIBLE to trim or 'shape' a sail without them.

RichH · Mar 13, 2012

Sublime said:
I will try this! I've also got a problem where it seems the boat is very tender. This is why I haven't been sailing with the jib. It seems to get overpowered really quickly so perhaps this is part of that problem.
I'm also learning to trust a keel boat (My experience is with dinghy sailing) so I thought part of it is me. I got a gauge to tell me how far I'm heeled over so that helps the "pucker" factor.

So when the sail is "just up" is that when the boom is at 90 degrees or is that when you start getting resistance on the halyard? And if I have, say, a 30 ft luff length, I put another 3" of tension on then test with your method of weather helm?
If it turns into the wind while testing, does that mean I need more or less tension?
.

Go to that 'article' and find that a sail that is "overdrafted" and "draft-aft" because the sail isnt full raised, ... will lead to a boat being VERY tender, aggressively heels over and slows down, wont point well, will have a LOT of weather helm - cranky!

When overpowered on a keel boat when above a beam reach in gusts, simply FLATTEN the sails and drop the traveller, first. In gusty conditions, its usually better to control ('play' or 'dump') the traveller, than the mainsheet; when 'playing' the mainsheet in gusts the boom can rise (vang stretch) and cause unexpected 'power-ups' of the mainsail ... this can also happen if the sail is 'overtwisted to spill wind'. Better to use the traveller, and if still overpowered then 'overtwisting' and/or reefing.

Forget the heeling gage, just close up the companion way, sail lockers, etc. and lock them so they stay closed ... and 'hold on' - it gets to be 'fun' after a while when you rise to the inbuilt 'confidence' that your keel boat has built-in.

;-)

Bill Roosa · Mar 13, 2012

I'm no expert
The sail has way too much draft and it is too far aft. Try tightening the main halyard and the clew outhaul to flatten the lower parts of the sail and bring the deepest draft forward. You can then sheet in the boom and get the upper part of the sail working correctly.
Alternately you can just sheet the boom in and stall the main at the bottom to get the upper leach to stay quiet. I think that has something to do with not having the jib up and "flow through the slot". With the jib up you are probably not going to get this BTW.

Joe · Mar 14, 2012

RichH said:
..............When overpowered on a keel boat when above a beam reach in gusts, simply FLATTEN the sails and drop the traveller, first. In gusty conditions, its usually better to control ('play' or 'dump') the traveller, than the mainsheet; when 'playing' the mainsheet in gusts the boom can rise (vang stretch) and cause unexpected 'power-ups' of the mainsail ... this can also happen if the sail is 'overtwisted to spill wind'. Better to use the traveller, and if still overpowered then 'overtwisting' and/or reefing. ..................
;-)

He doesn't have a traveller, Rich.... any alternative suggestions for Sublime to handle the situation? I don't think his vang is too powerful either, so we've got quite a challenge here.

What do you think about evaluating upper batten length or tension to help with the shape once he gets the hoist right?

Cayennita · Mar 14, 2012

More halyard tension will remove the scallops and bring the draft further forward. Also need to tighten the outhaul more. Go to the black band. One way to put more vang tension is to sheet in the main really hard and then the vang. When easing the main sheet, the vang is already tight and makes the job easier. By the looks of the tell tales, the main needed to go out some more. Also remember that the jib will help to keep the boat from rounding up. Add a flattening reef. That's about 10" up on the leech from the clew. A flatter main will help, specially in conjunction with a cunningham.. Have you set the mast with the correct luff length? It might need more rake.

RichH · Mar 14, 2012

Joe said:
He doesn't have a traveller, Rich.... any alternative suggestions for Sublime to handle the situation? I don't think his vang is too powerful either, so we've got quite a challenge here.

What do you think about evaluating upper batten length or tension to help with the shape once he gets the hoist right?

If you're referring to the 'shape of the curve in the upper panels' he can use tapered battens and or use two sets of battens ... one set for light winds, the other for high winds. Most folks never seem to adjust the compression in the battens for different wind/wave conditions, thats why Id suggest to simply sand down and taper a batten set and make them 'all purpose' battens matched to his usual 'crew weight' and sailing load.

Simple speak: The more the amount of draft in the upper panels, the more speed/power is derived from the 'top' of a sail.
For above 12-15kts. you usually want 'more straight'/less curved battens especially on a 'tender' boat that wants to heel over and with a light weight crew .... for less heeling.
You set the batten curve by the amount of compression you put into the batten - less tension for flat battens for 'speed sailing' (and light winds) ... and more compression and curved-forward battens (and more sail draft) to power/'punch' through steep waves.

This analogy follows standard practice of setting up the SHAPE of the sails:
FLAT sails for very light winds and sailing FAST in relatively flat water - a high-speed shape ('high gear').
FULL draft sails for 'punching' through waves - a power shape - LOW GEAR. (use this shape when 'reefed' too so you can 'punch' with 'power' ... a flat sail wont develop 'power')

When the winds go to 12-15kts, 'twist' is relatively un-important as the 'wind gradient' is less pronounced as when in 'mild' wind speeds .... and the sailmaker usually already designed-in the amount of proper 'twist' for that wind speed for 'normal' sheet tension and traveller position.

How do you 'adjust' to get the 'max.' out of the sails? or setting the amount of draft for the day's wind/wave conditions:
1. Set the batten compression for the day's expected wind/wave conditions
1a. Set for the desired helm balance (so-called weather helm) by additionally adjusting for correct halyard/cunningham tension ... do this while sailing close hauled.
2. Then while still closehauled, Adjust the mainsheet outhaul in/out while carefully watching the speedo ... you get 'best' AMOUNT of draft when you get the max. speed reading from the speedo - always a 'balance between a 'speed shape' and 'power shape'. this may change the helm balance, if so go back to 1a.
3. same thing with the jib fairlead car ... watch the speedo for max speed while adjusting the car fore or aft.
4. then recheck all the tell tales for minor corrections of trim and shape, etc.

Don Guillette · Mar 14, 2012

In reading all the comments I'm totally amazed, where on the web could a mate go and obtain the quality sail trim info that's provided on this forum? The answer is NO WHERE!! I'm really proud to be a part of the sail trim forum!! If mates like Joe from San Diego, RichH, Kiprichard, merlinuxo, Justsome guy, CW Kemp, Bill Rossa and Cayennita can't figure out a sail trim problem, the problem doesn't exist.

Merlinuxo - why are the sailors faces blacked out -- are they undercover sail trim experts operating incognito!?!?!

A picture is worth a thousand words but sometimes it's hard to figure out what's going on. Sublime, you need to try Joe from San Diego's advise on the leech line and follow RichH advise on the halyard. It doesn't look like your at full hoist. I prefer to use a Cunningham instead of the hayard.

The mainsail sail trim controls for twist are the boom vang and the mainsheet with the vang being the primary control. You need to crank on the vang until you can't go any further. If most of the twist isn't eliminated then grab the end of the boom and pull down and see what happens. A traveler has nothing to do with the situation at hand because the traveler only controls angle of attack. You'll never eliminate all the twist in a sail anyway because the sail maker builds twist in the main and jib. The reason he does is the wind blows 60% harder at the top of the sail then at deck level and without built in twist you couldn't control the sails.

I think Kiprichard is onto something when he suggests the sail is old and past its prime. You may not be able to eliminate the twist and I don't see the top telltale as it's probably curled behind the sail.

Tell me how to improve (pic included)

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