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  #11  
Old 02-08-2012
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Killarney...
Sailboatdata sez your mainsail area is 453 sq. ft. Wind load in pounds on a sail per US Sailing is sail area times wind speed squared times .0043. If your trysail is about a third of your mainsail's area, in a 60 knot blow, the sail load would only be about 2300 pounds. So the load on a single line (and block) would be 2300 pounds, which gives you a safety factor of over two for the expected load using the 5000 pound block in a 60 knot wind. The block's load would approach SWL with a wind of about 88 knots.
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Old 02-08-2012
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Thanks for the calculation, my trysail is about 90 sq ft, so about 20% of the main. I used your formula and got just under 1400 lbs at 60 knots and just under 2000 lbs at 70 knots. So considering that I would use it as a turning block that would make the load somewhere between 2800 and 4000 lbs. The 5000 lbs is the safe working load of the block - with the breaking strength at twice that I would assume. Not sure what the 8500 lbs block would be used for - what a beast it would be.

As for hooking up the sheets, I would have to use the cleats since I don't have a slotted toe rail - just the fancy and not very functional teak toe rail (good for keeping your feet onboard though). I have a couple of really big snatch blogs but if the shite hits the fan I have them tasked for the parachute anchor set up like the Pardeys suggest with a bridle and I might well heave-to with the trysail still up and sheeted in tightish.
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  #13  
Old 02-09-2012
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Quote:
Originally Posted by killarney_sailor View Post
BTW, I don't think I can tie my boom out of the way on deck since it has a rigid vang.
I have a rigid boomkicker also. I slide the traveler all the way to one side with some slack in the main sheet. I use a dock line to pull the boom as far to the opposite side as possible. Then I grind the main sheet in to hold the boom. Works a treat.

As far as loads are concerned the load that the block will see may be up to twice the sheet load depending on the angles in and out of the block.
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Old 02-10-2012
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Several years ago in the Gulf of Alaska with a moderate gale approaching we decided to rig the trysail -- not so much because we would need it, but to try it out in windy conditions. (Prior to this time I had hoisted the trysail at the dock / anchor several times, but had not done it underway with the wind/seas getting up.)

On the recommendation of a crew member (very experienced guy, 100,000 sea miles, circumnavigator, etc.) we rigged the clew of the trysail to the outhaul of the mainsail. We immediately discovered that the sail was not cut to be rigged thus -- although the foot was tight, we couldnít get the boom end down far enough to get the leach tight. The result was we had a big belly in the sail, couldnít point very well and we were heeling too much (especially when we came off the wind a bit.)

We then re-rigged everything so the clew was sheeted to the leeward quarter with a big snatch block (acting as the turning block) and hence to the primary sheet winch. With it setup in this fashion the sail was very flat, the boat pointed higher, and heeling was reduced. I should add that itís a good idea to work out how youíll tack with the trysíl as well. On our boat the mainsheet, boom and topping lift complicate tacking the trysíl. (Perhaps this is the reason that some people suggest securing the end of the boom to the deck -- it clears the area where the clew of the trysíl needs to pass when tacking.)

My guess is that you can get a sailmaker to cut a trysail that can be rigged to the boom, but most storm tryís are cut to be sheeted directly to the deck.

Such an arrangement also letís you adjust the height of the set with a line running from the tack to the deck at the base of the mast.

IMO, the whole deal (getting the main out of the way, the trysíl set, tackable, trysíl down and out of the way and main re-set when things calm down) is a lot easier if the trysíl is both set on itís own track and is rigged to be sheeted independently from the boom/main. In a perfect world, the trysíl should probably have itís own haulyard as well -- it took us about an hour to figure out how to lead the main haulyard through the lazyjacks to get the trysíl set properly. (Another reason why you should practice the set and stow of the trysíl before you need it. )
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Old 02-10-2012
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I have rigged the trysail at the dock/anchorage a couple of times to the end of the boom and the cut of the sail looks ok. I will try rigging it to the quarter and see what it looksl like. My guess would be that it it cut to be used with clew to boom but I will see. The boat has a separate trysail track and dedicated halyard so that part is fine. Have to do some experimenting and I probably should try it some time when it pipes up a bit (35 knots say) just to figure out things like how high up the track it should go and what the shape is like overall.

Thanks all for the advice.
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Old 02-11-2012
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You could also try contacting the sailmaker to ask him how he figured the sail to be set.
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Old 02-11-2012
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Quote:
Originally Posted by SVAuspicious View Post
I have a rigid boomkicker also. I slide the traveler all the way to one side with some slack in the main sheet. I use a dock line to pull the boom as far to the opposite side as possible. Then I grind the main sheet in to hold the boom. Works a treat.

As far as loads are concerned the load that the block will see may be up to twice the sheet load depending on the angles in and out of the block.
That sounds like a good way to do it with boom down as low as possible and tsecured out of the way on one side or the other. I made a foldable boom arch to hold the boom up when not in use to eliminate any thrashing from side to side in a beam sea if motoring and to take the strain off the topping lift but getting it down seems like a better way when using the trysail. Aren't most trysails designed to be off the boom/outhaul and the traveller system? I have never even considered setting mine up on the boom.
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Old 02-11-2012
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I'm settling on parameters for having a trysail built. I am trying to follow the conservation here to make sure I get this right. The sail's foot is to be a foot shorter than the boom, allowing the clew to be hauled out to the boom end, which I envision being lashed to the gallows in the center notch (with the mainsheet hauled in tight to hold her down). The trysail plan is 24 percent of mainsail area with a tackle angle of 12 degrees so the sail clears the furled main. Don't expect to be trying to sail upwind with this setup, but just taking the point of sail to avoid lee hazards or the danger semicircle of a storm while hove to to make a slick to sit in while battened down. Am I getting this about right? Thanks for any comments...
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Quote:
Originally Posted by smurphny View Post
Aren't most trysails designed to be off the boom/outhaul and the traveller system?
I was talking about securing the boom. Trysails generally sheet directly to a block on the deck or toerail and on to a winch.
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  #20  
Old 02-11-2012
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Built for the boat.

Quote:
Originally Posted by fryewe View Post
I'm settling on parameters for having a trysail built. I am trying to follow the conservation here to make sure I get this right. The sail's foot is to be a foot shorter than the boom, allowing the clew to be hauled out to the boom end, which I envision being lashed to the gallows in the center notch (with the mainsheet hauled in tight to hold her down). The trysail plan is 24 percent of mainsail area with a tackle angle of 12 degrees so the sail clears the furled main. Don't expect to be trying to sail upwind with this setup, but just taking the point of sail to avoid lee hazards or the danger semicircle of a storm while hove to to make a slick to sit in while battened down. Am I getting this about right? Thanks for any comments...
I think how it is done varies from boat to boat. For example, most of the boats I have seen out cruising - crossing the South Pacific do not have a boom gallows and most, or at least a great many, have a rigid vang so you really cannot drop the boom to the deck in the traditional way. With the rigid vang, the mainsheet and a preventer in the opposite direction from the mainsheet I think the boom will be pretty stable. We have done this in 55 knots but the waves were not huge in the 15-20' range.

A trysail that is 24% of main seems a bit large to me, but I have inmast furling so it is quite easy to make my main this small or smaller, although it takes the center of effort quite far forward, which might be a good thing for heaving to without a jib or with only a storm jib.
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