Hi The loos tensions that people are using on the C27 varies so much.I used some from a web site that also showed those recomended by Mr Toss. When I looked at and tried these tensions all were so low that the leeward shrouds were not just slacking but loose. Can you provide the tension settings again. Why is 20% of breaking strain not a good number for the C27 Thanks Paul
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Never slack
You never want to see the shrouds loose, never. 10 - 15% of the maximum tension is plenty to keep them looking good and functioning perfectly. You could tighten them more but I don't know if it would do more than put excessive loads on your chain plates and maybe throw too much pre bend into your mast. You could be sailing with a banana for a stick!
You never want to see the shrouds loose, never. 10 - 15% of the maximum tension is plenty to keep them looking good and functioning perfectly. You could tighten them more but I don't know if it would do more than put excessive loads on your chain plates and maybe throw too much pre bend into your mast. You could be sailing with a banana for a stick!
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Brion Toss
Maybe...
Hello, What numbers did I recommend? How are you measuring the tension? Are you sure of wire diameter? I am asking this because it should be very easy to keep the leeward shrouds from getting too slack. If you are getting to 20%, you are at a fairly high tension for other than out-and-out racers, so either something is amiss or you are driving this boat way hard. Let's eliminate some variables. First, is this a deck-stepped mast? If so, have you seen any birds bathing in a pool at its base? If so, the deck or compression post is giving way. Fix it. If not, is there any indication that your chainplates are rising? It happens. Next, is there any chance that the wires have been loaded past their elastic limit? It isn't easy to do, as it involves loads over 60% of break, but it can be done. Which brings us to the next question: what do you mean by "loose"? The leeward shrouds will always be looser than the weather ones, because the weather ones always stretch. What you want is the right tension on each component, to compensate for the loads imposed by typical conditions where you sail. So for the same size wire you'd tune tighter in San Francisco than Seattle. If you put 20% on and don't need it, your mast won't mind — much — but you'll be needlessly loading rig and hull, accelerating fatigue, for no benefit. In fact, if the jibstay is too tight you could be over-flattening the sail, for an actual loss in performance. Even if 20% turns out to be right for the uppers, by the way, you'll want much less on the shorter lower shrouds. Fair leads, Brion Toss
Hello, What numbers did I recommend? How are you measuring the tension? Are you sure of wire diameter? I am asking this because it should be very easy to keep the leeward shrouds from getting too slack. If you are getting to 20%, you are at a fairly high tension for other than out-and-out racers, so either something is amiss or you are driving this boat way hard. Let's eliminate some variables. First, is this a deck-stepped mast? If so, have you seen any birds bathing in a pool at its base? If so, the deck or compression post is giving way. Fix it. If not, is there any indication that your chainplates are rising? It happens. Next, is there any chance that the wires have been loaded past their elastic limit? It isn't easy to do, as it involves loads over 60% of break, but it can be done. Which brings us to the next question: what do you mean by "loose"? The leeward shrouds will always be looser than the weather ones, because the weather ones always stretch. What you want is the right tension on each component, to compensate for the loads imposed by typical conditions where you sail. So for the same size wire you'd tune tighter in San Francisco than Seattle. If you put 20% on and don't need it, your mast won't mind — much — but you'll be needlessly loading rig and hull, accelerating fatigue, for no benefit. In fact, if the jibstay is too tight you could be over-flattening the sail, for an actual loss in performance. Even if 20% turns out to be right for the uppers, by the way, you'll want much less on the shorter lower shrouds. Fair leads, Brion Toss
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Paul Cairoli
Response to Brion
Hi I was out of town so could not respond until now. The variables you mention are not a factor I dug up the sheet on your recommended tensions It shows 3/16 uppers at 640 to 840 or 14% to 18% of break strength...thats not bad The lowers however show 5/32 at 280 to 320 or 10 % to 11% It is the lowers that are slack on the leeward I just wanted to know why these figures were so low ( if indeed they came from you ) the same page also shows guys using even lower figures and most in the more traditional 15 to 20 & range. I use 15 % now I use a Loos guage to check What numbers do you currently think on the Catalina 27 Thanks in advance for taking the confusion out of of these numbers Paul
Hi I was out of town so could not respond until now. The variables you mention are not a factor I dug up the sheet on your recommended tensions It shows 3/16 uppers at 640 to 840 or 14% to 18% of break strength...thats not bad The lowers however show 5/32 at 280 to 320 or 10 % to 11% It is the lowers that are slack on the leeward I just wanted to know why these figures were so low ( if indeed they came from you ) the same page also shows guys using even lower figures and most in the more traditional 15 to 20 & range. I use 15 % now I use a Loos guage to check What numbers do you currently think on the Catalina 27 Thanks in advance for taking the confusion out of of these numbers Paul
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Brion Toss
Progress
Hi again, Thanks for the follow-up. Try 12% on the lowers, but beware more. Again, too much tension simply loads up the rig, mast, and hull, without producing any benefit. And if the lowers are disproportionately tight, the top of the mast will curve to leeward above the spreaders. Some slack on the leeward side is normal and desirable; the question is, how much? Next time you are under way to weather, get down on the leeward side and check the turnbuckles. If the shroud seems loose to you, back the turnbuckle off until it is utterly slack. Then take up until you just begin to feel resistance. That's probably where you want that wire to be. Tack and repeat on the other side. This is the last step in any full tune, the grace note following the dockside part. For more on this, I've got that video... Fair leads, Brion Toss
Hi again, Thanks for the follow-up. Try 12% on the lowers, but beware more. Again, too much tension simply loads up the rig, mast, and hull, without producing any benefit. And if the lowers are disproportionately tight, the top of the mast will curve to leeward above the spreaders. Some slack on the leeward side is normal and desirable; the question is, how much? Next time you are under way to weather, get down on the leeward side and check the turnbuckles. If the shroud seems loose to you, back the turnbuckle off until it is utterly slack. Then take up until you just begin to feel resistance. That's probably where you want that wire to be. Tack and repeat on the other side. This is the last step in any full tune, the grace note following the dockside part. For more on this, I've got that video... Fair leads, Brion Toss
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Paul Cairoli
Thanks
Thanks the 12% seems right ,infact that is where I ended up.. Now I am going on line to order your video Paul
Thanks the 12% seems right ,infact that is where I ended up.. Now I am going on line to order your video Paul
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Paul Cairoli
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