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  #1  
Old 04-29-2008, 09:09 PM
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wind_apparent wind_apparent is offline
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pocket luff sails with a trapeze?

has anyone used a pocket luff sail on a trapeze equiped boat? would it be possible? Would have to figure out the spreader issue I guess. the spreaders would have to go on after the sail, and be sturdy enough to support a person on the trap, would this be possible? any Ideas?
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  #2  
Old 04-29-2008, 09:24 PM
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waikikin waikikin is offline
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Wind apparent, maybe some velcro or zip on sails, velcro seems to work well on surfboard legropes with plenty of load
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  #3  
Old 04-29-2008, 09:30 PM
Chris Ostlind Chris Ostlind is offline
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Some years ago, there was an early iteration of the solo performance planing skiff called the MX-Ray. It used a luff socked main for upwind work and it flew a spinny for offwind.

The spinnaker mast "tang", if you will, was a re-enforced section of the sock with, I believe, a hard collar or stout webbing that wrapped around the mast in a pocket sewn into the luff sock securely.

The whole deal was hung from a carbon stick that was self supporting.

The boat was difficult to learn to sail, but when it was hooked-up, it ran like a bat.

Chris O
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Old 04-30-2008, 05:20 AM
Doug Lord
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The main on my first foiler were designed with a "luff pocket" as well as to be reefable. The rig was stayed-no spreaders. It could easily have used a trapeze. The sail had a three section zippered luff.
Attached Thumbnails
pocket luff sails with a trapeze?-aeroskiff_trial009_small.jpg  
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  #5  
Old 04-30-2008, 07:01 AM
bistros bistros is offline
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Quote:
Originally Posted by wind_apparent View Post
has anyone used a pocket luff sail on a trapeze equiped boat? would it be possible? Would have to figure out the spreader issue I guess. the spreaders would have to go on after the sail, and be sturdy enough to support a person on the trap, would this be possible? any Ideas?
It's been done. Search on "Bucko" to see a well documented build. One of the guys at my club has built a modern Moth that uses a stayed pocket luff sailboard style rig. The Hoot is definitely worth a look as well - no trap but it fills most of your checkboxes.

I'm looking at doing a second rig for my boat with a rotating mast next year - I've got the carbon tube (I-14 mast) and we're thinking about stays and rigging. Take a good look at the Moths to get an idea of how to handle the stays.

FWIW, pocket luff sails may be an issue at some locations - race rules require that there be some method of dropping sails either by the crew or rescue folks from a technicality standpoint. I personally hate having to fight for rigging space to rig a boat on it's side in the dinghy park.

Then there's money. Pocket luff designs for what you are building aren't cheap or easy to get right. If you've got the budget, go for it. If you want to get foiling on budget, I'd think about staging the risk over time, with a conventional rig to start and progressively more complex over time (as you can afford it). I first trialed my boat with a sailboard style rig, then a 505 main on a Proctor D tube - a combination that is proven, available and well known. Now I'm moving to the chop top full battened sail on the Proctor D, then we'll get the carbon tube trialed next. Incremental progress and risk.

Debugging design issues and tuning is really hard and critical. Eliminating variables and using known components makes the process far easier. I'm perfectly aware we've compromised potential performance at first, but it's enabled us to get the boat right in stages.

In all reality the performance potential given up on rig compromises is minuscule in comparison to the software improvement possible in the operator. I know that even with a aluminum tube and a conventional main sail the area needing improvement on the water the most is me.

Cheers!
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  #6  
Old 04-30-2008, 01:02 PM
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Hansen Aerosprt Hansen Aerosprt is offline
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Very Possible.
Either an opening in the mast luff sleeve with connection to the mast or a direct attachment to the sail. This sail has a 40cm wide luff sleeve.
- Bill

pocket luff sails with a trapeze?-am1a.jpg
pocket luff sails with a trapeze?-am44a.jpg
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Old 04-30-2008, 08:45 PM
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wind_apparent wind_apparent is offline
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Quote:
Originally Posted by Hansen Aerosprt View Post
Very Possible.
Either an opening in the mast luff sleeve with connection to the mast or a direct attachment to the sail. This sail has a 40cm wide luff sleeve.
- Bill

Attachment 20855
Attachment 20856
Thats a really nice sail Bill, where did you get it? how do the spreaders work on a moth? I can't seem to find it on any of the construction blogs, and there aren't alot of close up pictures.......would that kind of spreader system support 85kg on a trapeze? I know that hydro moths sometimes have spreader problems on a good crash, so I would hate to crash with it under tension.... tahnks for the input.......
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Old 04-30-2008, 08:52 PM
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wind_apparent wind_apparent is offline
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[quote=bistros;199064]I

Debugging design issues and tuning is really hard and critical. Eliminating variables and using known components makes the process far easier. I'm perfectly aware we've compromised potential performance at first, but it's enabled us to get the boat right in stages.



/QUOTE]

I think I'm going to use a swift solo mast, (known bend, just the right height, and I know its going to be strong enough) and a 2.7 meter boom (to get the sail area up to 10.75sm from 9.97sm).....so probably a track sail to start out, but as I get better, and the boat gets better, maybe try some new Ideas. I might try to see if someone that builds moth sails already would put one together for me.......
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  #9  
Old 04-30-2008, 09:05 PM
Doug Lord
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Sail

Bill Hansen is one of the best there is at the kind of sail you need.
http://www.hansenaerosports.com/
Here are the stats from the "Bucko" site(definitely has the numbers to foil-could use skinnier hull):
http://www.bucko.com.au/new%20boat.htm
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  #10  
Old 05-01-2008, 01:18 AM
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Hansen Aerosprt Hansen Aerosprt is offline
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WA:
I recently made that sail for Andy Mills' Fastacraft Prowler (Moth.) The rig is fairly standard for that boat. More pics are here: < http://www.hansensails.com/Forum/for...ts.asp?TID=115 > Sorry, but I can't say much about a trapeze on a Moth - no experience there.

Quote:
Originally Posted by wind_apparent View Post
Thats a really nice sail Bill, where did you get it? how do the spreaders work on a moth? I can't seem to find it on any of the construction blogs, and there aren't alot of close up pictures.......would that kind of spreader system support 85kg on a trapeze? I know that hydro moths sometimes have spreader problems on a good crash, so I would hate to crash with it under tension.... tahnks for the input.......
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  #11  
Old 05-01-2008, 01:18 AM
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Hansen Aerosprt Hansen Aerosprt is offline
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Thanks Doug!

Quote:
Originally Posted by Doug Lord View Post
Bill Hansen is one of the best there is at the kind of sail you need.
http://www.hansenaerosports.com/
Here are the stats from the "Bucko" site(definitely has the numbers to foil-could use skinnier hull):
http://www.bucko.com.au/new%20boat.htm
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  #12  
Old 05-01-2008, 10:09 PM
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wind_apparent wind_apparent is offline
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Quote:
Originally Posted by Doug Lord View Post
Bill Hansen is one of the best there is at the kind of sail you need.
http://www.hansenaerosports.com/
Here are the stats from the "Bucko" site(definitely has the numbers to foil-could use skinnier hull):
http://www.bucko.com.au/new%20boat.htm
been talking to him on the Hansen sails forum as well as here, so we'll see what comes about.
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  #13  
Old 05-01-2008, 10:16 PM
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wind_apparent wind_apparent is offline
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Quote:
Originally Posted by Doug Lord View Post
Bill Hansen is one of the best there is at the kind of sail you need.
http://www.hansenaerosports.com/
Here are the stats from the "Bucko" site(definitely has the numbers to foil-could use skinnier hull):
http://www.bucko.com.au/new%20boat.htm
so I looked up the Bucko, funny how close our numbers were to eachother's, tells me I'm probably right in there...... shows that you can't really mess around "too" much and still have the boat perform......
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