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Old 03-05-2013
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Re: Spinnaker Pole Rigging

Quote:
Originally Posted by Faster View Post
Absolutely... but I think it's too bad that that terminology has become synonomous, and is widely published as you've noted..

The guy is often referred to as the 'afterguy'... making sense of the term foreguy as it opposes the aft pull and provides down pull too.

An end for end 'downhaul', esp if run to the mast base, has no 'forward' component, only 'down'. I suppose if the downhaul is run forward to a deck block and then aft, it qualifies as a 'foreguy'..

Ah well... like you say, as long as everyone on the boat understands the term, we're good... We had our own name for the cunningham... 'sly pig'... got some funny looks from guests on that one...
Where the distinction becomes significant is in larger yachts with larger sails that really load up the pole. The closer to the wind one sails, the greater the apparent wind and the greater load on the afterguy, pole. The lifting force on the tack end of the pole really becomes quite enormous and one seriously needs a "down haul" (as you say) on the tack to hold the pole end in place. The afterguy positions the pole fore-in-aft, the foreguy/down-haul positions the tack end of the pole up-and down. Close reaching, with the pole near the headstay, one needs the foreguy/down-haul as nearly vertical as possible to avoid introducing unnecessary compression loads in the pole. On a larger yacht, a lower bridle is not suitable for this as the forward diagonal too sharply loads the pole, and more so if the tacking point of the guy/downhaul is aft of the apex of the bridle. (To say nothing of the loading on the deck fitting of the fair-lead for the guy/down-haul itself.) While I have never run the numbers, I'm guessing that at about 30 feet LOD with a roughly 10' pole is about the limiting length for a lower bridled pole and end-for-end gybes. On our boat, with an 18' pole and a 1570 SF Spinnaker, our foreguy is led to a point about 5' aft of the stem-head to a pad-eye bolted through deck and on the underside, to a bulkhead below. While one might argue that this is a less than optimal position when running off, at that point the apparent wind on the sail is lower and the fore and after-guys work together to hold the tack down, albeit both at relatively shallow angles. Considering the foregoing, "down-haul" logically seems to be the more apropos. Unfortunately, using it at this stage of the game would be confusing after so many years (old dogs, new tricks and all that)...

FWIW...

PS: I apologize to the OP if this thread drift/leeway into technical minutia adds little to his comprehension. It's all only terms/words and, different ships, different long splices, eh?
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Last edited by svHyLyte; 03-05-2013 at 11:06 AM.
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