Thread: GIS sail tweaking

In the works! I put a clamshell Ram brand rodholder on one knee that is fully adjustable as to angle and pitch, so that I can troll while sailing offshore. Over the weekend I realized that if I stick a wooden pole in it with a camera gimble on the end, I can get my waterproof camera away from the boat at any angle I want (John Goodman style!), to better film going upwind when an extra camera holding hand is not available. Now I'm at work staring out the window at decent wind, dying to get out on the water to test it!

What is interesting about the vid, to me at least, is how stable the boat was with the sail flat in 15 knots, just a trace of weather helm.

Symphony #7 next time? (my fav after 9)

Both are really nice symphonies. From #7 I really like 2:nd mov (Beethoven - 7th Symphony - 2nd movement - YouTube). Thank you for making more videos!

... yes, I'm envisioning the tempo as matching a nice sized ocean groundswell.

I've lost track where all of the bleater-vang-downhaul discussions are so figured this belongs here. I set up an adjustable bleater and vang-haul just to see how all of this could potentially work. In the video the bleater is first and the dual fore and aft vang setup is after the cat. From playing with this in my back yard I'm pretty sure the dual vang wins hands down for sail control. The bleater and vang was just not able to get good luff tension and the leech is probably too closed off. Won't know until I try it on the water. Going sailng with this rig tomorrow so we shall see.

I'm really curious to see what happens on a run with tne sail shifted forward of the mast as far as it will go.

I'm actually very happy with the single downhaul so not sure if the extra complexity of another line will be worth it. I'm thinking even if I stay with the stock single downhaul this adjustable rig can teach me what the optimum amount of sail balance is since I'll be able to make changes on the fly.

Originally Posted by SimonLew

...the dual fore and aft vang setup is after the cat. From playing with this in my back yard I'm pretty sure the dual vang wins hands down for sail control.

During much of this vang/vanghaul/bleater discussion I've wondered about a set-up like this. In my mind though, I envisioned a single line running from the tack to the deck to the boom and back a couple of times so that one pull tightens the luff and the vang simultaneously. But I don't know if that's desirable or not. And it wouldn't allow for the balance adjustments like you've created with the independent tackle. Do tell what you learn.

Howdy,

I really don't like the idea of moving the boom fore and aft relative to the mast while sailing. I think it looks like more trouble than it is worth and will mean the sail is flopping around when the concentration should be on the steering.

It makes more sense if the adjustments can be done singly - like on a conventional rig. but here the bleeter is, in effect, the gooseneck. A non adjustable function.

So I am much more comfortable if it is a simple bit of rope that is there to prevent anything silly from happening.
The bleeter is a really simple idea.

It means that the EXACT same ropes are used as the original rigging scheme, no additional blocks or bits.

I'd recommend that people try the fixed bleeter for a few sails before adding adjustment to it. If only to start giving a sense of how it works in standard form.

There are not any serious risks with experimentation - but I really want people to see the simplest possible versions as standard. Also to use them as a baseline for comparison.

I'm writing this for people who might drop by and not be aware of the background discussion which Simon has been part of. This post can be read months or years later so I need to include this disclaimer.

That said ... I'm interested to see how things go Simon.

MIK

Also .. I think there is a geometrical observation here.

A normal boom vang on this size of boat will normally be maybe 2.5ft back along the boom from the mast. Give or take.

In other discussion on this others have found that they think the sweet spot is when the vanghaul is about a foot behind the mast.

Why the discrepancy?

I think it is because the relevant reference point for comparison with a conventional vang is likely to be the tack of the sail ... which is well ahead of the mast.

So I would be inclined to think that about 2.5ft back from the tack would be the maximum distance back as a starting point. This makes the distance of the vanghaul along the boom to be much less relative to the mast. This is what has been observed by two users so far ... but as more experience is gained we'll get a better idea.

The way to think is that the vanghaul has a mix of functions ... it is still the main way of providing downhaul tension. And this tension is split between the luff and leach.

If the vanghaul moves too far back then luff tension will be lost as load is transferred to the leach.

MIK

Originally Posted by Boatmik

Also .. I think there is a geometrical observation here.

If the vanghaul moves too far back then luff tension will be lost as load is transferred to the leach.

MIK

That's exactly what I'm seeing even before the boat goes in the water. I have this set up so that the vanghaul can be easily slid fore and aft to change the ratio of luff versus leech tension. There's nothing like mocking something up and seeing how the bits interact.

As to shuttling the sail forward off the wind. I'm thinking, if it works, it's only useful on long runs. For example something like the Texas 200 where you are on a run for a long time. Around the buoys it would be way to fiddly, although with a crew it's no worse than setting and dousing a spinnaker.

For those who may unearth this post in the far off future, I want to reinforce what MIK said about the stock setup. It's super simple and it just plain works. The boat is fast as stink without any mods. I just can't help but tinker with it .

Originally Posted by engblom

Both are really nice symphonies. From #7 I really like 2:nd mov (Beethoven - 7th Symphony - 2nd movement - YouTube). Thank you for making more videos!

Here you go Engblom, but I skipped the music, as the sailing sounds were much better left alone! Wind, waves, buoy hooting and the sealions.



Cheap boom cam compared to video maestro JG, but it worked - until that one swell slam knocked it a bit askew!

Tuning notes. I slid my yard attachment point up to 60" from where it was (57"), leaving the bleater length alone at 16" from luff to leading edge of the mast. I know this sounds weird, but my pointing with the boom on the leeward side of the mast improved a bit, but my pointing with the boom on the windward side of the mast was not as good. I'm going to split the difference next time out, and try a yard attachment point of 58" from the luff.

Simon, that is a pretty cool rig!

New question I haven't seen asked/answered: Any reason not to attach the tack of the sail to a pad-eye on the boom, similar to what some of us use on the yard at the throat?

I spent a few hours yesterday sailing with the dual vang setup and shifting the boom fore and aft. Learned a few things. A couple totally unrelated to the vangs. Before I get into the observations I want to comment on the overall experience of sailing the Goat with this setup. In a nutshell, it ruins the joy of sailing a simple boat and turns it into something similar to a sloop with lots of strings to pull, but we kind of expected that.


The winds were 10-12kn max with some gusts higher, water was flat. My wife was with me and did vang duty.


One goal of this was to be able to easily move the sail back and forth to fine tune balance when pointing. Reasonable changes of a few inches had surprisingly little effect on the helm. I think this is because the whole sail is not being shifted but rotated about the yard attachment point. Sliding the boom forward puts more sail area down low in front of the mast but it also rotates the peak down and aft. So I call the helm balance experiments a bust.


While messing with this, I was obviously paying a lot of attention to the helm. The helm is pretty neutral, sometimes I have a little weather helm and other times just a touch of lee helm. I chalked this up to changes in conditions or Neptune's fickle mood. I now know what is causing the difference and I can't believe I did not see this before. On the bad tack I have slight weather helm and on the good tack I have slight lee helm. Has anyone else noticed this? The only thing I can think of is that the draft is further back on the bad tack than on the good one.


We were sailing with several other boats and on several occasions got to chase around a Cortez Melonseed. Overall the Goat and Melonseed were about even, and I know this sounds crazy, but I think we were doing slightly better against him on the bad tack. You'd never notice this sailing against another Goat since we all seem to rig with the boom on port. A slight bit of weather helm is supposed to help pointing so maybe that's the reason. I'm having a hard time believing that the sail shape on the bad tack is providing better drive upwind.


The other purpose of the dual vangs was to see if moving the sail very far forward of the mast would settle the boat down on a run, in heavy air. The wind was not strong enough to induce rolling down wind. It does seem that the boat is more stable with the sail very far forward. Gybing is not fun as the boom is very low. The transition from upwind sail location to downwind is a bit of a pain. So overall not conclusive but has some potential at great cost to user friendliness.


We practiced sailing by the lee with the rig set to normal balance. I was not able to reliably reproduce the sail control MIK shows in his sailing by the lee video. We did almost capsize because of a huge accidental gybe. Need to practice this technique a lot more.

Here's a little video of the Melonseed shot from our boat.

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I was out this morning and also did some experimenting. Winds were light and water was mostly flat, so it was a good day to mess around without worry of anything catastrophic happening. I even spent a while practicing gybes, something I'm still not comfortable with in the Goat.

Experiment one was to try the full-length battens again. I had ditched them last year, soon after my first sail. I couldn't see that they were doing any good and, since the batten pockets on my sail had no ends, they were always working loose. When I had my sail in for some work this winter, they fixed the pockets, even installing tensioners at the luff end. (I didn't ask them to do this and they didn't charge me. I think the sailmaker just couldn't help himself.) I thought maybe the battens were worth another try now that they would put some tension in the sail.

Result: I seemed to have slightly more control going upwind, but that could be my imagination. On the other hand, I suddenly had serious lee helm on starboard tack in light air. Luckily, it went away as the wind picked up. But it was definitely unexpected. And my leech flap was back. Bad. I never did know why it went away and now maybe I do. Maybe getting rid of the battens fixed it.

I also tried a bleater/vanghaul setup. I've been using a bleater all summer, but with my downhaul straight up and down. This is the first time I tried moving it back on the boom.

Result: I do NOT like what the bleater does to my mast when the vanghaul is tensioned. It looked like the rope would saw right through and sounded even worse. Every wave or puff would generate a horrid groaning noise. I couldn't stand it. I pulled into the wind after just a few minutes to put the downhaul vertical again. Before I try that experiment again, I'm going to have to find a way to avoid that damage. Maybe a fat, soft hunk of nylon for the bleater? (I'm using 3mm spyderline now.) Or some sort or parrel?

As I was really unsure about my yard lash location, I did some video forensics to figure out where people are lashing relative to distance from the luff with a full sail. This data is not on the wiki. Turns out, even at my 57" spot, I am further up the yard than everyone. Really nice looking sail sets are at about 53". This corresponds to yard attachment distance of roughly 41% of the total distance from throat to peak. The nicest looking sail set is the video of Mik sailing Bruce's Goat. Hope you don't mind me attaching the video here!


BTW Wood, funny that you mention putting the transom ratchet block on backwards. I did the same thing when I put it on two sails ago, and it made sheeting very interesting - one of those "what the heck is going on" moments. That is one sweet looking sail you have.

Simon - yeah simple is nicer! I have just two lines other than the sheet (downhaul, outhaul), and that's enough for me.

Paulie - agree about the biting bleater, I tweaked my downhaul so now it pulls down on two places - straight down, and also at my outhaul block lashing, one foot aft of the mast. This is nice, because it adds some vanging, but when I tried to untie my bleater later, the knots were very snug, like the bleater had been under a lot more tension. I use a soft 8mm line for my bleater.

Bob - great idea about the tack attachment. I use the rope equivalent now, two wraps of spiderline. For reefing, a solid atachment at the tack that can be opened and closed easily would make just too much sense.

Paulie - I've only used the bleater with a vertical downhaul and that was fine. I can see how it will get super tight when you move the downhaul back. What about using a piece of flat webbing (like on a tie-down ratchet strap) for the bleater? Should distribute the pressure on the mast over a nice wide area.