Thread: GIS sail tweaking

(See the next post by Paulie below. He balances out his comments in this post somewhat. I think it is valid to have both comments here - MIK)

Wow. You guys had me second-guessing myself so bad that I went out to the garage -- the detached, unheated garage -- in 14F/-10C weather to lay the sail out and take another look at it.

Head: Whatever curve the head may or may not have had is already lost in the scallop pattern created by stretching against the lashing points. The deviation, if there was one, must have been less than an inch.

Body: A close look does reveal a touch of broadseaming. There are 3 seams running parallel to the luff (no, that's not the way I would cut it) and each picks up maybe 1/3" of seam toward both ends (head and foot, due to the orientation). So it is not "dead flat", but neither is it enough to show any obvious wrinkle or bulge lying there on the garage floor. Again, sail stretch will surely give me more fullness over time than those seams.

I have other complaints about this sail. It came with 2 full-length battens, but the batten pockets don't close properly. So the battens start to work their way out the end over time. As it happens, I found the battens to be worse than useless and stopped using them, so this doesn't really matter. But why not close the pockets properly? It would only require a few stitches.

The reef points are just wrong. The first set is far too high, discouraging me from taking in that first reef. The second set is also too high, causing the boom and yard to bang together. I'm having new, more reasonable, reef points put in.

The grommets are already oxidized. I sail in salt water and don't have time to hose the sail down after every outing. The grommets should be able to handle that.

Some of the stitching is already loose after 1/2 of a season of sailing and reasonable handling.

The kicker? The sail is from Duckworks BBS, cut (I believe) to MIK's plans. I'm not recommending it to new GIS builders.

DW BBS is offering the sail now with reef points and excluding the full batten. The full battens were a pain (I lost one when in worked out and slipped into the dark waters of Lake Sunapee) and the 1st reef point was far too high, my sailmaker threw in a new first reef between the foot and the original reef point. These changes are reflected in the new DW sail, from what it looks like on the site, and many other people who built or ordered their sails custom have the similar set-ups, I think. The last "handkerchief" reef location, I'm not sure about if it has changed or not. These changes were all discussed at length in various locations on this forum depending on the builder.

I agree with the lack of curve along the head and the flatness of the top end of the sail. Mine, over two seasons has pushed out a bit and stretched, and now I'm pretty happy with it, but I wouldn't say ecstatic. It works for what I need it to do. I can do with a little less power up top anyway, especially in the Atlantic when I'm alone, though in light airs it is annoying.

No problems with my grommets. Mine are brass-- they are tarnished but they are supposed to do that. Maybe you got a bad set?

I think it can be agreed upon it's a good starter sail but definitely not a racing sail.

My apologies. I should never post anything before my second cup of coffee in the morning. I always come across too negative when I do.

The Duckworks sail did what I wanted it to do: it got me on the water quickly at a rather low price. A sail made from scratch by someone local would surely cost me twice as much. It is "good enough" -- the existence proof is that I am using it and will continue to do so for the next couple of seasons (at least) with only minor modifications.

Moreover, I am still such a newbie with the lug rig that I know I wouldn't get the most out of a better sail. Not yet. By the time I'm ready for a better sail, I will be a better lug rig sailor and the additional expense will be more justified.

So I guess I could recommend this sail, especially if DW has fixed the design issues with the batten pockets and reef points. But I would still caution buyers about what it is and isn't.

Originally Posted by paulie

So I guess I could recommend this sail, especially if DW has fixed the design issues with the batten pockets and reef points. But I would still caution buyers about what it is and isn't.

The DW sail is what it is, the cheapest entry level sail it would be possible to make, and it should probably remain so. Higher level sails with three rows of reefpoints and everything done to make it as good as possible are going to cost at least twice as much as the sail from DW.

The current version of the Duckworks sail doesn't have the full length batten pockets, which seem to have been a bad idea. It should be possible when ordering a sail to specify the position of the reef points, my recommendation would be three reefs 600 mm apart, that leaves the third reef without the yard and boom clashing. It should also be possible to ask them to tweak the edge curve along the head for the bendiness of the spar, most sailmakers are possibly underestimating the flexibility of the wooden yard as specified and cutting the head too straight. Also builders are probably often getting too enthusiastic with the plane and ending up with a too floppy yard. Woodeneye got his (not from DW) sail working better once he had a stiffer yard.

In terms of tweaking an existing sail, something that could be tried that might be worthwhile is to reinforce the luff with another layer of sail tape. The DW sailcloth is quite light, if there is only one layer of reinforcing along the luff, that's probably too light for the downhaul tension people are getting. The recommendation from others using lugsails seriously is two layers of sail tape folded and sewn along the luff so the luff is 5 layers thick.

Another thing, if the head curve is minimal, is to go to a stiffer yard. Make another one with dia say 45-48 mm. If you suspend your yard between two sawhorses, hang 10 kg of the middle and it bends more than 50 mm, it is too floppy.

The edge round in the head should match the flexibility of the yard. It will also vary a little according to sailcloth weight and stiffness, and how the sailmaker has done the broadseaming, but a rule of thumb calculation from Stewart Dabler is as follows:

Suspend the yard with sawhorses at the throat and peak attachment points. Hang one third of the sail area in pounds off the halyard attachment point and measure the deflection. This deflection should (more or less) match the amount of head curve. "One third of the sail area in pounds" is 35 pounds or 16 kg. If these 40 mm dia wooden yards are bending 50 mm with 10 kg hung of the middle, they'll bend about 80 mm with 16 kg, so the head will need about this much round in it. I think Mik put up a pattern for a basic sail with no broadseaming with about this much round along the head.

My feeling is that within all this, a stiffer yard is better, up to about twice as stiff as most of the wooden ones we are seeing, but the main thing is to have yard stiffness and edge round matching. If you're ordering a sail, make sure your sailmaker is on to this,if you have an existing sail, measure it and the yard stiffness and make a stiffer yard if necessary.

Ian

My sail was made by Stuart at Dabbler, the first GIS sail he made. I figured it was a bargain--within a few dollars of the Duckworks price but shipping was included so it was actually cheaper.

Mine was ordered when things were slow and I've seen more current prices which are more than I paid; but I'd say his sails are well worth the money.

My batten pockets are closed at the front and open at the back; the battens extend outside the sail so they can be tensioned by the small cord affixed at the open end of the pocket. That's the same way battens have been secured and tensioned for decades, I believe.

Dang dilemma - A few of our sails are I think too straight in a couple of areas, primarily the head and foot, for the flexibilty of a standard GIS yard and boom.. As mentioned, we can make stiffer yards and booms to match the sails, or we can live with it, or we can suck it up, and have new sails made.

Middle - I checked out the Dabbler website, and came across a picture of a proa that I think my friends made in Miami. It was a double ender - in that you shifted the entire rigging depending on your tack - the bow becomes the stern, and the stern the bow.

Paulie, I'm with you on the second cup of coffee. It's like wake up, grumble grumble, first cup, grumble, second cup, dang it's a beautiful day outside.

Originally Posted by warm beer

Paulie, I'm with you on the second cup of coffee. It's like wake up, grumble grumble, first cup, grumble, second cup, dang it's a beautiful day outside.

Exactly! Before the first cup, I not even capable of posting anything, so I'm safe. After the second, I'm feeling human. In between... well, if I were a better engineer, I'd develop a way of locking my keyboard until I have achieved a certain level of caffeination each the morning.

786......Explosive and Drug Detector.CCTV, GPS, GSM, USB, Spy Camera, Bio-Matric Products, Wireless Terminals, LCD, CRT, MP-3, MP-4, iPOD & Accessories, MultiMedia Products, TV and Full Range CCTV Surveillance Security Systems., Picture of The golde

Maybe it can be tweaked? Has a USB attachment.

Perfect!

Has Mik's post above been hacked?

Read 98 and 99 and click on link.

They're trying to control Paulie's erratic and impulsive morning pre-caffeine behavior.

It's not spam ... just vBulletin parsing the name of the page. It is a bit bizarre!

Michael

I'm a bit of a coffee freak myself, as long as it's espresso. Have you tried Civet coffee, not cheap, but worth the experience? I first heard about it in Cape Town last year.

ThinkGeek :: Civet Crap Choice Coffee

Haven't tried civet coffee yet, but it's on my bucket list. In the meantime, I roast my own, so I get to tweak it just the way I want it. The lighter the roast, the more caffeine. Bet you can guess that I like it VERY light!