Talked with Aerotech support, they recommended I release the tension in the sail battens during storage.
So now I always release the batten tension, because a given sail may not be used for weeks to months at a time.
First time I went to use one of the sails that I had released the tension on, I forgot
, rigged the sail and it looked good so got out on the water. After a while I started to think the second batten up could use a little more tension, saw some minor creases, and as I was tensioning it I remembered I had released the tension on all the battens on all my sails.
So why did the sail look good with battens that I had released?, I had slowly over tensioned them to remove "new" wrinkles. The first time I released the batten tension they were loose, but the sail was over stretched, and slowly shrank back until the battens were tight. So now I back off the screws until close to backing out of the tensioner, but enough tension so the tensioner is trapped in place. Do it every time now because I do not know how long it will be until I use that sail again.
Does it make a difference?, I think so, had a light 8-9 knot day today with an occasional 10 knot gust, and got up more than I expected, easier than expected, and had longer flights with the 8.0 Freespeed and AFS F1080 wing. Why?, I think because the sail had better shape, the shape it was designed to have, versus the over stretched shape I had created by slowly over tensioning the battens.
Each brand of sail will be different but in most cases you shouldn't need to touch batten tension from one session to the next.
Batten tensioners are not sail tuning devices on most sails, and the key is not to over tension battens beyond their role in removing wrinkles in the batten pockets.
Any batten put under compressional load will tend to bend more easily and will therefore be less effective in its primary role of adding stability to the sail panel.
With some cam'd sails it can be different, depending on how the cam is pushed agains the mast.
What can happen with all sails is that materials can appear to stretch a bit when very wet, and it's then tempting to over tighten a batten tensioner. If that sail then dries out in a period of hot and dry weather then the effect is to reveal the overtighening as the sail shrinks a little back to its dry state. At that point, too much batten tension can lead to the batten setting in a permanent curve if stored for a while.
The answer for most people will be to not over tighten the tensioners in the first place.
But, for sure, it does no harm to take tension off the batten tensioner by half a turn if you intend to store your sails for a long period.
Select to expand quoteBasher said..
Each brand of sail will be different but in most cases you shouldn't need to touch batten tension from one session to the next.
Batten tensioners are not sail tuning devices on most sails, and the key is not to over tension battens beyond their role in removing wrinkles in the batten pockets.
Any batten put under compressional load will tend to bend more easily and will therefore be less effective in its primary role of adding stability to the sail panel.
With some cam'd sails it can be different, depending on how the cam is pushed agains the mast.
What can happen with all sails is that materials can appear to stretch a bit when very wet, and it's then tempting to over tighten a batten tensioner. If that sail then dries out in a period of hot and dry weather then the effect is to reveal the overtighening as the sail shrinks a little back to its dry state. At that point, too much batten tension can lead to the batten setting in a permanent curve if stored for a while.
The answer for most people will be to not over tighten the tensioners in the first place.
But, for sure, it does no harm to take tension off the batten tensioner by half a turn if you intend to store your sails for a long period.
Thanks Basher, that was helpful, I am usually in hot weather, and as a kid I did strip a few bolts on dirt bikes! Will keep in mind the affect of a sail getting wet on batten tension. There were certainly light wind days where I was almost getting up, and thought maybe the sail needed more batten tension, when the problem was really my poor technique, fortunately Andy Brandt straightened that problem out.
What I found is after 1-2 complete turns of the batten tension screw, if I tried pushing inward and the tensioner moved, it meant I had released enough tension, no need to unscrew further and risk have the batten adjusters get out of the rope tether.
Select to expand quoteManuel7 said..
A friend of mine, by fear of breaking tensioners, doesn't even tighten his!
What sail are they using? Aerotech batten tensioners are very durable, took years of over-tensioning without a problem!
Select to expand quotemathew said..
What problem is being solved here [ by releasing batten tension ] ?
The constant tension on the sail panels in hot humid weather causes new vertical wrinkles to form in the sail panels because the plastic panels are slowly stretching out. By releasing batten tension after use, the sail panels can relax so that the next time they are tensioned the sail has the correct shape without vertical wrinkles in the panels.
An extreme example is for an Ezzy sail I saw, they ship them with battens pretensioned, and in the early days of covid they were sitting in the hot sun for a month in steel shipping containers in the Port of Miami. I know someone who bought an Ezzy sail from a local shop who got their equipment from the Port of Miami. The guy was unrolling the sail for the first time on the beach, still had the protective paper/foam (wind caught it and I grabbed it). Then he rigged it and asked me to take a look at it, between every batten on the leech end the sail had these big stretched out scallops that he could not get rid of, and he was using a brand new correct Ezzy mast using the factory down haul setting. I think the problem was the sail got cooked in the shipping container and the plastic panels stretched out on the leech end due to the batten tension and prolonged high temperatures inside the shipping container. I contacted Ezzy sails about it and they only said they now ship their sails by plane, wonder why?
I just read that the temperature inside a steel shipping container is "double" the outside temperature! So a 90 degree day in Miami would make the inside 180 degrees!
www.shiplilly.com/blog/complete-guide-to-ocean-shipping-containers/
So this solution is only for people from Miami buying Ezzy sails during the pandemic? :)
Oh you guys!, I sail year round in SW Florida home of the Endless Summer, beat that! But in Summer my high wind sails do not get used, and in Fall/Winter/Spring my low wind sails do not get used. So a given sail can sit for months at a time, and according to the manufacturer I should release the batten tension when storing the sails. I started the post with that for those of you with poor or failing eye sight
Select to expand quoteImax1 said..
Can we PLEASE , have your view on failing eyesight .
And the ideal amount of downhaul.
Select to expand quoteSandman1221 said..mathew said..
What problem is being solved here [ by releasing batten tension ] ?
The constant tension on the sail panels in hot humid weather causes new vertical wrinkles to form in the sail panels because the plastic panels are slowly stretching out. By releasing batten tension after use, the sail panels can relax so that the next time they are tensioned the sail has the correct shape without vertical wrinkles in the panels./
What you are suggesting is the limit for elastic-deformation (aka the ability to return to original shape) becomes plastic-deformation.
Depending on whom you talk too, either you never get plastic-deform if you stay within elastic-deform, or you do get some which tends to be seen as a memory-effect.
I personally _feel_ that some (most?) sails need to be sailed a few times before it becomes "correctly set" ... the material beds-in. Once that point is reached, the material doesn't change much. But that could be bias.
I have considered removing batten-tension, but getting the tension correct in the first place, then having to redo the same tension each time, is just time-wasting.... I'd rather go sailing, than to tweak battens for the next eternity for what I _feel_ is of no benefit.
If you need to let the tension off to stop distortion, then they were too tight in the first place. That or your sails are crap.
The bottom 2 battens on every overdrive I've owned and that's quite a few has ended up being to short after a few months use so something definitely gives.
while it might not be necessary to release batten tension when your not using the sail it must be better to store stuff not under tension
Select to expand quoteBen1973 said..
The bottom 2 battens on every overdrive I've owned and that's quite a few has ended up being to short after a few months use so something definitely gives.
while it might not be necessary to release batten tension when your not using the sail it must be better to store stuff not under tension
This usually a result of incorrect-original-length batten - I have had sails with this problem where one batten couldn't be adjusted any further.
Most sail brands uses n hex-key-tensioner system where the batten has a threaded-sleeve-thingy; this usually uses a 8mm rod or thereabouts. ( Other manufacturers have a different system, eg: Neil Pryde ). Just grab a bit of old batten-rod, then cut off about 1cm or 2cm of rod -> insert it into the sleeve. Tighten it back up.
Note that running-out-of-adjustment sometimes is incorrectly diagnosed... sometimes sand/salt gets into the adjustment mechanism, which causes the thread to become jammed resulting in no-more-adjustment. Cleaning the adjustment mechanism ( which means pulling completely apart ) usually solves this problem.
Select to expand quotemathew said..Ben1973 said..
The bottom 2 battens on every overdrive I've owned and that's quite a few has ended up being to short after a few months use so something definitely gives.
while it might not be necessary to release batten tension when your not using the sail it must be better to store stuff not under tension
This usually a result of incorrect-original-length batten - I have had sails with this problem where one batten couldn't be adjusted any further.
Most sail brands uses n hex-key-tensioner system where the batten has a threaded-sleeve-thingy; this usually uses a 8mm rod or thereabouts. ( Other manufacturers have a different system, eg: Neil Pryde ). Just grab a bit of old batten-rod, then cut off about 1cm or 2cm of rod -> insert it into the sleeve. Tighten it back up.
Note that running-out-of-adjustment sometimes is incorrectly diagnosed... sometimes sand/salt gets into the adjustment mechanism, which causes the thread to become jammed resulting in no-more-adjustment. Cleaning the adjustment mechanism ( which means pulling completely apart ) usually solves this problem.
Yes that's the fix I came up with, had to do it on my old m2,m3 and m4's seems Severne like cutting battens to short
Select to expand quoteBen1973 said..
The bottom 2 battens on every overdrive I've owned and that's quite a few has ended up being to short after a few months use so something definitely gives.
while it might not be necessary to release batten tension when your not using the sail it must be better to store stuff not under tension
If I recall correctly from talks to sailmakers, if the tension is insufficient to damage the material then it doesn't matter if you leave it on. Easing tension too much can allow the sail material to crease, which isn't good.
One further issue is that some materials shrink with age and change size slightly with humidity, so over the long term the batten's required length may change.
