PaulGS
Member
As a novice I'd probably think a sail was fine unless it appeared visibly tattered - so how to tell?
How to tell whether a sailset is perfect, serviceable or worn out?
- Thread starter PaulGS
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penfold
Well-known member
Is it sail shaped? Specifically if you hoist it, tension the halliard to one grunt and trim in to telltales, if you then look up at the sail do the draft lines look like aerofoils and are they all similar in shape? Does the leach flap like a bird with a broken wing? Is the sail cloth crispy or floppy? There are more subtleties to it but that's a good start.
dunedin
Well-known member
Take photos of sails, both from on board looking upwards and from a friend in another boat or the tender as you sail past, then post on here and/or show to a sailmaker
Daydream believer
Well-known member
Buy a book on sail trimming. One with some pictures ( Not the ones you colour in with crayons 
)
It will explain sail shape & how to get the best use of it far better than you will get from comments on a forum. I suggest that you may find a copy of "Tuning yachts and small keelboats" by Lawrie Smith £ 2.65 Amazon. ( that is the cheapest book I can find there are others)That shows details of camber etc & how to trim the sails
If you cannot get these cambers it is a fair bet that your sails have had it.
For instance if the fullness of the main is too far aft it would suggest it has stretched. But looking at the pictures will show you where the 40% mark actually is. It will tell you how to use cunningham to get it back.
It will explain the difference in how a camber in a jib too far forward may be faster for a good helmsman, but harder for an average one. Because it needs more concentration. But someone on the forum telling you the flow needs to be forward may not be absolutely true for you.
Sail shape is not just a simple science. The sail has to be cut to the sailors needs & ability as well as the boat itself.
Sail shape is also a product of rig set up. I changed my fixed length forestay 5 times before I got the mast rake right. I also played with rig tension for several years until I found what is the optimum for me.
These changes made the boat better balanced. I change the sails regularly & that makes a big difference to balance. If your boat is heavy on the helm it could indicate a poorly set mainsail, a badly set up rig, or a multiple of factors. One needs to read up about it & study up on it then go & compare what you have read with what you have on the boat.
)It will explain sail shape & how to get the best use of it far better than you will get from comments on a forum. I suggest that you may find a copy of "Tuning yachts and small keelboats" by Lawrie Smith £ 2.65 Amazon. ( that is the cheapest book I can find there are others)That shows details of camber etc & how to trim the sails
If you cannot get these cambers it is a fair bet that your sails have had it.
For instance if the fullness of the main is too far aft it would suggest it has stretched. But looking at the pictures will show you where the 40% mark actually is. It will tell you how to use cunningham to get it back.
It will explain the difference in how a camber in a jib too far forward may be faster for a good helmsman, but harder for an average one. Because it needs more concentration. But someone on the forum telling you the flow needs to be forward may not be absolutely true for you.
Sail shape is not just a simple science. The sail has to be cut to the sailors needs & ability as well as the boat itself.
Sail shape is also a product of rig set up. I changed my fixed length forestay 5 times before I got the mast rake right. I also played with rig tension for several years until I found what is the optimum for me.
These changes made the boat better balanced. I change the sails regularly & that makes a big difference to balance. If your boat is heavy on the helm it could indicate a poorly set mainsail, a badly set up rig, or a multiple of factors. One needs to read up about it & study up on it then go & compare what you have read with what you have on the boat.
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Concerto
Well-known member
Welcome PaulGS to the wonderful world of sail trim.
Do you know what shape a sail should look like? If not you will not have a clue about the condition of a sail. There are plenty of videos on YouTube that should help.
Generally most sails will retain a good shape for 4 to 5 years before they start to stretch out of shape. This can be extended with higher quality sailcloth like Vecktran, but I doubt you have this. When sails are 30 to 40 years old then they are definitely shot.
As a novice, I doubt if your rigging is set up correctly. This will also affect your sail set with rigging too slack causing bad sail set. Then you need to know how much tension you need on the halyard to position the maximum chord section in the correct place to be similar to an aircraft wing. Sailing is about creating a similar lift to the aircraft wing. Then there is the sheeting angle to ensure the "wing" shape is at the correct angle to the wind for maximum lift. The position of the sheet can alter the twist in a sail, which again affects performance. Sailing is a cross between an art form and science. It is a steep learning curve to sail fast.
As a novice I would not worry too much about your sails at present, but learn the basics of sailing and hone these skills. When similar sized boats sail past you, look to see what is different in the way their sails are set. This is part of your learning curve.
I know lots of other owners think I have a quick boat as I sail with longer yachts which should be faster than mine. I can look at their sails and see what is wrong with them and how simple changes would improve their boat speed. There are plenty of sailors who are quite content to poodle along with poorly set sails and are just happy to be on the water, but I like going places and an extra half or three quarters of a knot can make such a difference over 10 or 12 hours sailing. So I sail further or arrive earlier for little extra effort.
Do you know what shape a sail should look like? If not you will not have a clue about the condition of a sail. There are plenty of videos on YouTube that should help.
Generally most sails will retain a good shape for 4 to 5 years before they start to stretch out of shape. This can be extended with higher quality sailcloth like Vecktran, but I doubt you have this. When sails are 30 to 40 years old then they are definitely shot.
As a novice, I doubt if your rigging is set up correctly. This will also affect your sail set with rigging too slack causing bad sail set. Then you need to know how much tension you need on the halyard to position the maximum chord section in the correct place to be similar to an aircraft wing. Sailing is about creating a similar lift to the aircraft wing. Then there is the sheeting angle to ensure the "wing" shape is at the correct angle to the wind for maximum lift. The position of the sheet can alter the twist in a sail, which again affects performance. Sailing is a cross between an art form and science. It is a steep learning curve to sail fast.
As a novice I would not worry too much about your sails at present, but learn the basics of sailing and hone these skills. When similar sized boats sail past you, look to see what is different in the way their sails are set. This is part of your learning curve.
I know lots of other owners think I have a quick boat as I sail with longer yachts which should be faster than mine. I can look at their sails and see what is wrong with them and how simple changes would improve their boat speed. There are plenty of sailors who are quite content to poodle along with poorly set sails and are just happy to be on the water, but I like going places and an extra half or three quarters of a knot can make such a difference over 10 or 12 hours sailing. So I sail further or arrive earlier for little extra effort.
Spirit (of Glenans)
Well-known member
There is an article on this very subject in YM's current (February) edition.
justanothersailboat
Well-known member
I've not worn out enough sails yet but I'm starting to pick up a simple rule of thumb for the undemanding sailor:
- If you have to ask, they're not perfect.
- If they make a nice curve and the trim adjustments have the expected effects, there's life in them
- if they're baggy and sailing upwind is getting frustrating, they're knackered
Different people will draw the line between 2 and 3 in different places. Regardless, everyone within a mile or two can see exactly what you do with your sails and should be assumed to be silently judging you. Ignore their judgement as long as you are having fun, save up so you can get nice replacements when it's not fun any more.
- If you have to ask, they're not perfect.
- If they make a nice curve and the trim adjustments have the expected effects, there's life in them
- if they're baggy and sailing upwind is getting frustrating, they're knackered
Different people will draw the line between 2 and 3 in different places. Regardless, everyone within a mile or two can see exactly what you do with your sails and should be assumed to be silently judging you. Ignore their judgement as long as you are having fun, save up so you can get nice replacements when it's not fun any more.
Birdseye
Well-known member
An interesting question. I have a new to me boat with sails from 2005. When I bought the boat I budgeted for new sails but on the few outings that I have done so far, the sails seem remarkably good. As a casual racer for 30 years I have previously done all the tinkering that Daydream believer mentions with good results so I am puzzled. We'll see if I am mistaken when there is more sailing come spring.
The best answer is racing the boat. If you dont finishe where you would expect to finish then there is something wrong and since it cant possibly be you, it must be rig or sails. Or maybe the crud attached to the hull.
The best answer is racing the boat. If you dont finishe where you would expect to finish then there is something wrong and since it cant possibly be you, it must be rig or sails. Or maybe the crud attached to the hull.
flaming
Well-known member
I've tried describing this twice, and deleted what I wrote because it was unintelligible. I'll try pictures.
This is a good sail.
This is not.
johnalison
Well-known member
We may be able to help from photos, but ultimately the best way is to take someone with you who is reasonably expert. Alternatively, wait until you have enough experience to judge properly, but this could take some time. Old or badly-set sails will still work but you may lose three quarters of a knot in speed or fifteen degrees going to windward.
