Here is my jib leech flutter experiment from last Sunday 07/08/2018. It was a fun day on the water, but inconclusive.

https://www.youtube.com/watch?v=sS7H-3xAFnE



Edited by leeboweffect on Jul 13, 2018 - 11:18 AM.

--
Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
--

If the leech is still loose you should try all the way up on the plate. Are you sure it’s not fluttering from the luff? The blocks on the hulls are far apart, the ideal spot for upwind is near the hiking strap. You can tie a line side to side with a couple loops for the blocks and do some additional testing. Also converting your sheets to 2:1 is a good idea, probably with the same blocks you have, can’t see them well on your video.

The leech on my5.7 flutters quite noticeably if the 2 short battens are missing. They seem to stiffen, or keep the shape better.
As soon as it starts fluttering, I know they have fallen out.

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--

you can also use a pigtail on the tack to raise the sail up a little, this has the same effect as going to a higher clew plate hole, but gives you finer adjustment since you can determine the exact length.

-Mike

From what I've read/experienced with flapping jib leeches. There isnt a jib sheet angle that fixes it because it's the cloth that's stretched out on the leech relative to the rest of the jib. You basically either have the sail recut, or add a leech line as a half fix to take up some of the slack and support the back edge of the fabric. I just replaced the sail when it got really bad and i couldnt get it to stop.

Quote

There isnt a jib sheet angle that fixes it because it's the cloth that's stretched out on the leech relative to the rest of the jib. You basically either have the sail recut, or add a leech line as a half fix to take up some of the slack and support the back edge of the fabric.

a wrongly angled sheet will pull on either the foot or leach and can lead to flogging - so i wouldn't count that out.

a leach-line (for me) is the last resort to help reduce flog in a "spent" sail. but this typically induces more cure/hook to your leach ... which is not good so it's a trade off - less flog, more hook - neither good



Edited by MN3 on Jul 16, 2018 - 07:38 PM.

Andinista

The blocks on the hulls are far apart, the ideal spot for upwind is near the hiking strap.

Still working on something to try that. This darn thing called time keeps getting in my way...

--
Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
--

mikekrantz

you can also use a pigtail on the tack to raise the sail up a little, this has the same effect as going to a higher clew plate hole, but gives you finer adjustment since you can determine the exact length.

-Mike

Very much worth trying for this and a couple of other reasons.

--
Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
--