Is this a G10 rig?

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Re: Is this a G10 rig?

Post by Sailing-61-North »

Thanks.
S/V Arctic Tern
Freedom 33
1981 - #37
Prince William Sound - Alaska

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Re: Is this a G10 rig?

Post by Sailing-61-North »

Also I like the design. Too much roach or just right?
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Freedom 33
1981 - #37
Prince William Sound - Alaska

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seadago
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Re: Is this a G10 rig?

Post by seadago »

Sailing-61-North wrote:
Thu Sep 23, 2021 6:33 pm
Also I like the design. Too much roach or just right?
Mmmm.... not an easy answer to that question! Roachy and full-battened, those sails are quite powerful. They are also very efficient. Kudos to Ullman. This also means a they are a handful to manage when the wind pics up very quickly. Too much/little are relative terms. I can tell you that were I to make those sails again, I would cut them little less roachy. Not much, maybe 5 or 6 inches at the widest chord of the roach, and the sail istelf maybe a foot or so smaller at the foot. This will also help with the battens getting cought less on the topping lift of the boom when you tack.
For the rest, the three-dimentional design is just right!

To give you some idea, the original reported total sail area of the F30 CK with the wrap-around sails was 37 sq m. I always felt the boat was underpowered with these. With the new sails, I have 43 sq m, and possibly I am marginally over-canvassed. Between these two thresholds, I think you have elbow room to play with the design.

Rafa
Rafael
s/v Nausikaa
SSR 30570, sail GBR 4619L
F30 CK (Hoyt), wishbones, centreboard, G10 rig. Built by Fairways Marine, Humble, UK, '82
Beta 16 hp with two-blade prop

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Re: Is this a G10 rig?

Post by Sailing-61-North »

Thanks Rafael.

Just pulled the boat for winter. Working on the winterize process. I have till April before it goes back into the water so just trying to figure out the whole sail thing right-ish. I have time.
S/V Arctic Tern
Freedom 33
1981 - #37
Prince William Sound - Alaska

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Re: Is this a G10 rig?

Post by Sailing-61-North »

Hi Rafael and others.

I am presently working on figuring out the "Reef" locations in relation to the wishbone. This setup is new to me so sorry for all the questions. Just trying to wrap my mind around the reefing process.

Reef#1. Where, in relation to the chocker, do you have yours? If I remember from a previous chat it was above the chocker? I was hoping to have it deeper to start out with.

Reef#2. Pretty obvious that this one and the 3rd reef are above the chocker. When these are placed I assume the wishbone needs to be dropped and the outhaul slackened.

In general when putting in a reef is the process just bringing the sail down or am I suppose to do something with the sail below the reef point? Like I said new concept for me.

I did remember from our previous conversation about keeping the reef point proportional between main and mizzen.
Attachments
Draft - Round 1 Main
Draft - Round 1 Main
Mainsail.DS1#1.jpg (44.82 KiB) Viewed 2900 times
S/V Arctic Tern
Freedom 33
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Prince William Sound - Alaska

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seadago
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Re: Is this a G10 rig?

Post by seadago »

Hi there
At one point, it was a new concept for all of us!
I can only tell you what I did, and what I learned from my mistakes, so it´s not “advice”!
I modelled it on paper. Made a print to scale of the boat from the original brochure, and then overimposed the sail design from Ullman to the same scale. Example below.
On this “template”, I placed two bars representing the booms, also to scale. The “correct” angle of the boom forward WRT the horizontal I eyeballed by looking at every pic and clip of a Hoyt CK 30 and 35 under sail that I could find on the web, and asked around in this forum and others.
Nausica rig layout v3.jpg
Nausica rig layout v3.jpg (22.86 KiB) Viewed 2881 times
This exercise helped. As you can see on my pic, the original cut by Ullman was more suitable to a sailboard than a boat, as the clew was way too high, and the tack way too low, on both sails. Based on this view, I asked Ullman to change the overall design to the red outline in the pic.

Now, on a normal fixed boom rig, where the boom and the foot of the sail are parallel to the horizontal of the boat, and both of these are at 90 deg to the mast, the reef attachment points on the leach and luff of the sail also need to be aligned with each other and close to parallel to the horizontal.
Not so in in our rig! The wishbone boom is not parallel to the horizontal, but at an angle. The luff reef attachment point needs to be higher than the leech point, so that the effective foot of the sail when reefed remains more or less parallel to the horizontal. How much higher will depend on the angle you carry your boom forward.

In your sail design, you will see the sailmaker put the attachment points for the reefs as if the sail were to fit on a “normal” fixed boom with a boom vang and/or kicking strap, where the boom is parallel to the horizontal and at 90 deg to the mast. This is what they would normally do, but it does not fit our rig. If you were to reef your sail with an angled boom, you’ll find that when the leech reef attachment point is brought down towards the aft end of the angled boom (as it would be under tension by the reefing line), the luff attachment point will sit very low, way below the choker of the boom. IMO (only my opinion based on my sails, with single-line reefing, and with the angle I carry my boom!), with the sail reefed, the luff reef attachment point should sit between one and two feet the boom choker, but not much more than that. This setup gives me the best sail shape when reefed, and also gives me sufficient room on the forward section of the boom between the arms of the wishbone to flake all the sail that falls below the reef.

In short, my suggestion is that you model this on paper first, and estimate where the reef attachment points should go according to the angle of your boom. I did it in Powerpoint, so you don´t need any special graphic design SW.
Below is also a pic of Nausikaa with the main on the first reef, and the mizzen on the second reef. This just to show you how my sails hang when reefed.
Hope it helps.
Rafa
Nausikaa reefed.jpeg
Nausikaa reefed.jpeg (388.78 KiB) Viewed 2881 times
Rafael
s/v Nausikaa
SSR 30570, sail GBR 4619L
F30 CK (Hoyt), wishbones, centreboard, G10 rig. Built by Fairways Marine, Humble, UK, '82
Beta 16 hp with two-blade prop

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Re: Is this a G10 rig?

Post by Sailing-61-North »

Wow thanks a ton. Made sense after reading that.
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Freedom 33
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Prince William Sound - Alaska

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Re: Is this a G10 rig?

Post by Sailing-61-North »

Something like this (See PDF)

1. Tack is approximately 2-ft off the mast ring. (See yellow double arrow).
2. Kept all of the reef points an equal distance from the wishbone.
3. Wishbone is basically fixed at it's height. I will have a line to raise and lower.
4. As noted it's not a roachy sail.

Other suggestions?
Attachments
Main Measurements with Wishbone Boom and Reef.pdf
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Freedom 33
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Prince William Sound - Alaska

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Re: Is this a G10 rig?

Post by Sailing-61-North »

Draft Mizzen PDF
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Mizzen Measurements with Wishbone Boom and Reef.pdf
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S/V Arctic Tern
Freedom 33
1981 - #37
Prince William Sound - Alaska

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seadago
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Re: Is this a G10 rig?

Post by seadago »

Hi

Yep, I think you've got the knack of it!

You've also got some flexibility to play around and fine-tune. Intuitively, the difference in height between the reef attachment points on the sail should be similar to the inclination of the boom, right? Well, IMO not necessarily nor exactly. Have a look at the drawing below. It shows you one of my sails reefed.
IMG_20211023_130049.jpg
IMG_20211023_130049.jpg (1.38 MiB) Viewed 2821 times
When you bring the sail down to the reef, the rackband (leashing line) will slacken: i.e. reducing the vertical length will increase the length of each loop around the mast proportionally, so the sail luff will come away from the mast. Once I set the reef, the last thing I do is take up the slack and re-tighten the rackband so the luff is once again closer to the mast.

That´s all well and good, but in those sections of the reefed sail that fall below the boom choke, the rackband will loop over the boom choke (as I hope it is shown in the drawing!). As you progress through the reefing schedule, there will be more loops of the rackband lying over the boom choke, as more of the sail falls below it. You should not be surprised if you find you need to bring the boom (and the boom choke) a foot or two down the mast in order to set your third reef and achieve a good sail shape.

Likewise the more loops around the mast you put on your rackband to attach the sail to the mast. More loops of the rackband will also give you considerable more friction to hoist and abate the sail. The more loops of the rackband are lying over the boom choke, and under tension by the weight of the flaked sail below, the more difficult will it be to re-tighten when you set each subsequent reef.

So you've got several parameters here to play with that give you lots of flexibility. You've got: (1) the height of the reef attachment points on the sail relative to each other, (2) how many loops you put on your rackband, (3) where you put them, (4) the height (angle) of the boom on each reef, and finally (5) the overall tension of the sail halyard.

On Nausikaa's main I have only two reefs, and I have two very old fashioned bead parrels at the head section of the sail (the section that is always aloft, you can see them on the pic in the post above) and three parrels at the bottom of the sail (the section that is aways, in all circumstances, below the boom choke. These parrels move freely up and down the mast and do not interfere with anything. In between, I have four loops of the rackband above the second reef, but only two between the first and second reefs. In consequence, I have only two loops of the rackband lying over the boom choke when I set the first reef, and four when I set the second reef. With this, I achieve a good reefed sail shape with low or moderate (in winds above 20+ knots) difficulty to re-tighten the rackband.

IMO, that's the great benefit of this rig compared to a mast rail & car system. It gives you lots of flexibility to fine tune, adapt to different conditions, and it is very easy to modify. Suggest you keep this flexibility element in mind, as it gives you lots of options.
Cheers!
Rafa
Rafael
s/v Nausikaa
SSR 30570, sail GBR 4619L
F30 CK (Hoyt), wishbones, centreboard, G10 rig. Built by Fairways Marine, Humble, UK, '82
Beta 16 hp with two-blade prop

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