Thread: GIS handling characteristics

I also wanted to say that this forum is totally awesome.

I wish that one day we could get all our Storer designs from around the world in one spot and spend a week tweaking rigs and sailing around and drinking beer and having bonfires and telling tall tales. I'll provide the humor by pushing my rig, capsizing and demonstrating efficient bailing techniques.

She really plowed through some seas two days ago with my mate on board, and I'm looking forward to some Maine Coast cruising. It's coming!

Actually, that is just what the Optimists do.

You just reminded me.

They adjust the foot lacing for different conditions. by inducing a curve in the foot. The gap in the middle is adjusted wider to power up the sail for hearvier crews, moderate weather or choppy water.

Or tie them with a bigger space at the ends and no space in the middle for lighter crews, stronger or very, very light conditions or flat water.

Or the gap can be placed where you want to move the maxdepth point in the bottom third of the sail.

Funny the stuff we remember.

MIK

OK,

Here's a good example of the wrinkles I'm talking about that I can't get rid of now.

This is just a representation, the winds were light and the contrast was good, so I took the pic. In heavier winds these are seriously degrading the performance of the airfoil (in lights winds too. How do I get this smooth?

The boom has been mentioned, as in: It needs to be stiffer. But my boom is pretty darn stiff already, unless it needs to be an I-beam. If that's the case, I can do that. I get about 17mm or less deflection with 25lbs of water.

I have also used a marlin lacing for the foot AND added an outhaul with one level of purchase to pull things tight.

What's a sailor to do, mates?

Actually, that doesn't look too bad. You're always going to have some wrinkles near where the mast intersects the spars on that tack because the sail is laying against the mast rather than assuming its "normal" curvature. Does it look smoother when you're sailing on starboard tack? I would experiment with individually adjustable tie loops for each grommet, and slack them well off in that area to see if that looks better. Adjusting the outhaul will also have an effect.

But if the overall sail shape is acceptable I don't think those wrinkles are seriously degrading performance. Plenty of top helmsmen get consistently good results from sails that have much more noticeable "speed wrinkles" than that. It's kind of amazing, but they actually don't seem to hurt much.

Grant

Originally Posted by Old Yeller

Actually, that doesn't look too bad. You're always going to have some wrinkles near where the mast intersects the spars on that tack because the sail is laying against the mast rather than assuming its "normal" curvature.

I should have been more specific, its not about the parts of the sail laying against the mast, but rather the horizontal wrinkles from the grommets up.

Does it look smoother when you're sailing on starboard tack? I would experiment with individually adjustable tie loops for each grommet, and slack them well off in that area to see if that looks better. Adjusting the outhaul will also have an effect.

No, it does not look smoother on starboard tack. I have done adjustments with the grommets-- they used to be tied down individually and I still had the same creases.

But if the overall sail shape is acceptable I don't think those wrinkles are seriously degrading performance. Plenty of top helmsmen get consistently good results from sails that have much more noticeable "speed wrinkles" than that. It's kind of amazing, but they actually don't seem to hurt much.

Grant

That is good to know thank you.

However, the higher the wind velocity, the more exacerbated the wrinkles become and I definitely feel that a smoother airfoil shape would considerably aid upwind performance especially, which seems to be doggy.

Goat Island Skiff (GIS) - systems for lug sails and rigs - Michael Storer Wooden Boat Plans The first picture of Mik here illustrates what I would like to get. Nice smooth airfoil for maximum pulling power.


ALSO

Anyone else have the Duckworks sail? Anybody think it's a little flat up at the head?

Originally Posted by callsign222

OK,

Here's a good example of the wrinkles I'm talking about that I can't get rid of now.

This is just a representation, the winds were light and the contrast was good, so I took the pic. In heavier winds these are seriously degrading the performance of the airfoil (in lights winds too. How do I get this smooth?

The boom has been mentioned, as in: It needs to be stiffer. But my boom is pretty darn stiff already, unless it needs to be an I-beam. If that's the case, I can do that. I get about 17mm or less deflection with 25lbs of water.

I have also used a marlin lacing for the foot AND added an outhaul with one level of purchase to pull things tight.

What's a sailor to do, mates?

Try more tension on both the foot and head, you should start to see horizontal creases along the boom stop and release a tad, put similiar tension along the yard.

Hate to say this but the cut and seaming of your sail is nothing like the one in the pic of Mik and I wonder about the round along the foot. I think the wrinkles could also indicate the yard needs to be higher.

I'll be interested to read Mik's thoughts.

Here's two more.

I don't have the advantage of Biting Midge to hang around his balcony and take pro shots of my sail while underway, so this will have to do. I want to re-iterate that this was a very calm wind kind of day, but the wrinkles are consistent regardless of wind, running diagonally from the boom up to the throat.

I will re-tension yet again the head and the foot, but there's not much more I can do.

Thanks for the suggestions.

Looks like there's a significant hard spot near the leach showing in your last photo, also. I would agree with the other gentleman that the cut and seam construction in this sail were not quite first rate. Consult with your sailmaker - unless he is you! ;-)

Grant

Hello Callsign,

Could this be caused by the way you attached the sail to the yard at the bottom? It seems that you are using 2 eyelets low on the yard; the lower one might be pulling the wrinkles in the sail. This lower eyelet is meant for putting in the highest reef only I think.

It also seems that a bit more tension is required on the foot as it is not lying flat on topthe boom. This should also provide a bit more draft low down in the sail.

Best regards,

Joost

Excuse me Callsign - I hesitate to out you - but when you take a lovely mannequin sailing, occasionally change her position. Haha!

Grant

Hi Christophe

Joost is right. Untie the reef point eyelet where you have it attached to the front of the yard.

Also, wasn't your sail designed for full length battens? I notice you don't have any installed in these pics, but then I seem to remember that they broke during one of your skirmishes out on the water? As an interim measure, perhaps make up a couple from strips of left over marine ply and make sure that you have good tension in them to induce the intended curve.

Bitingmidge's sail is a very nice sail with a nice depth of cut that doesn't seem to need it's battens. Yours is a somewhat flatter cut, so I think you need the battens.

Also try peaking your yard higher. Remove the block attached to the yard (the block serves no purpose here) to allow you pull the yard closer to the mast and move your downhaul attachment further forward.

OK, some definitely good progress today, and some great comments too, thank you and keep them coming, one step at a time I'll get this darn thing up and straight and running right.

Today, back to the lake, SOLO. I put in on the west side of the the southern end of the lake. You can see why a north wind helps. the wind was blowing consistently 10-20mph from the North, right down the lake, as opposed from the West, over the hills and mountains. This meant I had a good consistent, non-shifty wind. Finally.

FIRST: I lashed two 50lb bags of sand to the centerboard case on either side, tucked in underneath the seat. (see them behind me here with the blue strap)

SECOND: I cranked on the foot with my outhaul as much as possible. I then went sailing with full sail aloft.

On the water the boat was substantially much more stable, she wasn't slipping away from under me and out to God-knows-where. There was a stability factor there that I just didn't have before single-handed. Her pointing ability was better too. I was able to keep her relatively fast though a few times I dunked the leeward rail. "Time to reef her" I said. However, I still had wrinkles along the foot diagonally up to the throat.

I broad-reached to the opposite side of the lake into a calmer cove (John Hay Nat'l Wildlife Refuge) and anchored. I ate lunch, enjoyed the view, swam to the bottom of the lake and sat down and stared back up at my boat-- kinda neat. I did a backflip off the bottom of it too, like I was standing on a ceiling-- and landed back onto the boat. That was super neat! I digress.

THIRD: I reefed to the first level (below Mik's first level) and used Joosts clip on the tack which is a most easy method. I then reefed the grommets, and re-attached the outhaul to the clew, and pulled to get a very nice clean tight "new" foot to my reefed sail.

I raised the sail, cranked down on the downhaul and away we went!!!

She sailed admirably. Flat, stable, fast, pointing well. The sail did not have any wrinkles in it, and had a good depth for the amount of wind. I was very happy with the results.

However, when I got back into the harbor, the wind slacked up considerably, and now the sail was substantially too flat for the type conditions. I ghosted in, but a maybe loosened the outhaul and maybe the downhaul a bit? The outhaul is a pain because it was on the wrong side. Regardless, the top portion of the sail, the "handkerchief" portion above the very top reef remains very flat and somewhat useless in this kind of wind.

Joost and Woodeneye-- There is only one eyelet at the throat of the sail-- at the forward part of the head. I have a tie down around the yard there, and a second line attaching this eyelet to the front of the yard. This second line is useless, since the downhaul brings makes it go all the slack anyway. Which line do I not need?

I have including two pictures, one of the throat, and one of the outhaul. My boat is de-rigged, so the mainsail clew is not tied down since I use the mainsheet for that. Also, remember there is one reef tucked in.

Woodeneye, I lost a batten, but pulled the other one out since it had been mentioned maybe the battens were making the sail too flat, I was trying to get some camber into it. What does the collective think? I can add them again, I'd be happy too if this will improve things.

My sail is a standard Duckworks sail that I ordered from here. I had an extra reef added and grommets by a local sailmaker.

I am doing everything I can to eliminate problems on my end before tackling bigger problems. Everyday is better, the boat performs better and better. Part of these problems is my total lack of any sort of experience with a balanced lug and my sometime quixotic quest to go big or go home and run too much sail.

But I feel performance deficiencies. Feel them. It's tough to explain but I know what I should be getting and what I'm not.

Thank you all for you help, feel free to mention anything you might think is reasonable.

...and Grant, I moved my mannequin quite a lot, to her protest sometimes, but she's a good sport.

Someone mentioned getting her rigged in a parking lot. This is a good idea. If I get a breeze tomorrow up here at my house I will rig her and get a good shot of the sail from a distance so we can all have a better view of what's going on.

Again, some of the best sailing yet was today, I was really happy she was feeling like a real boat, it was good and I am happy!



OH and Joost, congratulations! Until Sunday...

Hi Christophe,

This picture of your lashing of the sail to the spar at the throat looks completely wrong. There's a very good thread by keyhavenpotter on getting this adjusted right - in one of the lug rig heaven threads I think. Get it right and it may solve many of the problems with the sail.



Sorry, too busy to write more, have to put the kids to bed...

Ian