Down Wind

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Shep Zedaker

I need rigging help with my 1993 H27OB. I want to gain more down-wind speed for club racing and cruising. I have been talking to sail makers who seem to like symmetrical spinnakers for racing and asymmetricals for cruising. The H27 model I have has a fractional rig with swept-back spreaders. I cannot go directly down wind with the main bent around the spreaders. And, since most polar projection plots show better speed, and maybe better distance made good, by gybing down wind, it seems that an asym. would be better. I have been watching the AC races in NZ and sometimes the boats fly asyms and sometimes syms. With both, they use a pole but all the asyms I see at the sailmakers don't use poles. What gives? What determines the change? When/why is a sym better than a asym. Should I get a sym even though I will never sail directly down wind because of my spreaders? Also, sail makers cannot tell me how to set up the spinnaker pole. How long of a pole should I use? How high on the mast should the end fitting/track be mounted? The Z-spar mast has a block and exit port for the spinnaker halyard already but no mounting for the pole lift. How/where should the pole lift and downhall be mounted? How much sail area should my spinnaker have? Where should the turning blocks for the sheets/guys be mounted?
 
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Jay Hill

Only a Few Answers...

...cause, quite frankly, that's a lot of questions! Whew! I'm not much into the super racer mode, but pole use on an asym is usually due to wind speed. Less wind, more need for a pole for asym. Plus, the asym pole may be used as a whisker pole versus a spinnaker pole. (whisker holds out the lee edge, spinnaker pole holds out the windward edge.) How to setup the spinnaker pole: I'd make the decision on "asym w/o pole," "asym w/pole" or "symm w/ pole" first. No need to buy and rig all the equipment required for a pole if you aren't going to use it, no? Let me see if I can help you along there. Pole: If you do decide you want a pole, it should be approximately equal to the J measurement on your boat. Roughly 11' 3" in your case. Pole Track Car: Not sure about the Zspar masts as I have Isospar with builtin track on front edge of mast. If Zspar has this, you can order a pole car that fits right on the front of the mast. The disadvantage is that with no external track, there are no "stopper holes" in the track to permanently adjust a pole car and therefore requires additional control lines and hardware to keep pole car in desired location. With an External Track, you can mount it where you can adjust the car to preference after your first time or two flying the chute. For installation purposes, I recommend a 6' track mounted with the bottom edge roughly 30" above the mast step. This is a really rough estimate, of course, but will cover ALL the bases of versatility. It also allows you to install a pole cleat at the top of the track for storage on the mast versus the deck or stanchions. I have seen boats with just the pole ring mounted directly to the mast, if the boat comes with a spinnaker, that's probably fine, but if you have to buy one (and would consider a used one that may not be the exact right measurement) a permanent mount will probably be in the wrong place. When flying the spinnaker, the pole should remain parallel to the water when the sail has maximum draft. (If you pull the pole down too far, it flattens the sail a bit and reduces power.) So, where you put the pole depends on the size of the sail as described below. (You can find out more information about Zspar equipment at www.rigrite.com. I didn't see any Zspar spinnaker gear there, but if you call them, they are VERY friendly and helpful. You might look at the Isospar section on masts to see what I'm talking about with "built-in" track.) Gonna skip the hardware questions for now and go straight to sail area. A main concern for ordering the sails is the length of luffs and the foot (symm.) and luff, leech, foot (asym.) For symm., the luffs should be +/- 8% of the "I" measurement and the foot should be roughly 180% of the "J" measurement. (I've got the formula for calculating the sail area given an estimate of draft at home if you want it.) So, using the measurements for the 75-84 models (since the 85-94 model information is not available) your luffs for symm would range from 34' 6" to 40' 6" and the foot should be roughly 20' 3". With a 6' range in the luff, the maximum draft position of the sail may vary a foot or two (or three) meaning the pole height will have to be adjusted. Knowing these measurements allows you to be flexible in buying a spinnaker. There are many a new spinnaker sitting in a loft taken as trade on a storm jib or the like because the owners did not know how to fly, nor did they care to learn how to fly a spinnaker. You might find one within your range w/o having to buy "new" or "custom". Back to hardware: No topping lift or foreguy? Yeah, me either until I did the nasty and drilled holes in my beloved boat to mount it all. (Big decision I had to make; took me three months to decide if I really wanted a spinnaker if it meant drilling holes for hardware. When I got a used spinnaker for $200 the decision became much easier.) The bridles on the pole will have rings in roughly the middle of the pole. If "J" equals 11' 3", then foreguy should be on deck roughly 5' 8" forward of the mast step. You might find that it in the middle of a hatch. (Not sure if your boat is this way; I had to move my foreguy forward of the hatch.) The topping lift should be positioned so that the pole can be lifted easily by crew; this means a favorable angle of lift from the block. Here I go again, but "roughly" 30-45 degrees out from the mast makes for easy lifting. So, mount the pole in "roughly" the right place and figure out topping lift mount point by using a line with 30-45% to the mast. Now you have to get the topping lift and foreguy across the decks and to the cockpit (or not) and find a place to secure them. This may mean more holes in either mast or deck for cleats of some kind. Sheet and guy blocks can be mounted via shackles to the toerail if you do not have sheet block mounting pads. If on the toerail, they should be as far aft as possible without interfering with helm, pushpit, or other local hardware. So, let's look at the damage with using a pole: Holes in mast to mount topping lift Holes in mast to mount pole track Holes in deck to mount foreguy hardware More holes in deck to run lines to cockpit Pole must be stored somewhere Hardware: Pole; Topping lift line, blocks, fairleads; foreguy line, blocks, fairleads; pole track (or car with control lines); pole track car; pole storage rig, sheet blocks Sail Characterstics: Nearly impossible to fly single-handed Damage with Asym. with no pole: Holes: None Hardware: sheet blocks Optional Hardware: Forespar for attaching spinnaker tack Sail Characteristics: gybes like a jib, can single-hand it if desired. Any questions? (Just kidding, but any added pull I would get from a symm vs. asym. is far outweighed (to me) by all the equipment, installation, handling, and cost.) If I need that little extra pull I'd buy a larger asym. Hope this helps.
 
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BKell

Hunter27 Spinnaker considerations

Your model of Hunter has a "J" dimension of 9.67' Whether to go to a Asymmetrical or Symmetrical chute depends largely on the type of racing you plan on doing and what the prevalent wind is in your area. Remember, the spinnaker size is governed by your local PHRF area check with your local sailmaker. If you sail in predominantly light wind (10knts or less) thw Asymm. is probably the right choice. If the wind varies a lot and the courses are windward-leewards, the Symm. chute is the best choice. BTW- The AC boats use "a" chutes in 15knts or less because they generate so much apparent wind which means they can sail at hotter angles. This is not the case on a Hunter 27. Also note that the AC boats have masthead chutes and oversize spinnaker poles which would be severely penalized in PHRF.
 
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