Thread: GIS handling characteristics

Sorry ... you got in before I had finished ... took a bit longer than I thought

Howdy.

I haven't found much trouble with reefing BETH or the GIS using the reef points only. I don't guarantee that you can get away without reef points, but I was able to find I was. The important thing is to use the same tie down method as that standard corner tie downs.



The tie down has to be OUT to the end of the boom (or to the normal clew and tack eyes) but also you need to drop a loop around the boom as well to hold the sail down to the boom. Otherwise the sail will bag out badly in gusts and overbend the boom as well.

I don't know about the depowering problem. The only possiblity I can think of off the top of my head is if there was too much sail in front of the mast ... sail was too far forward. But it would have to be quite a long way for the sail to power up in gusts.

It might be OK and the angle of this shot would tend to exaggerate the overlap



I can see you are having trouble keeping the downhaul in the right place. We will get to that in a moment.

The correct place for the sail is approximately (from the setup page - Goat Island Skiff (GIS) - systems for lug sails and rigs - Michael Storer Wooden Boat Plans)


If the 400mm distance gets too long then the sail will not depower as well. But I would expect quite a big distance more ... another 50 or 100mm won't change the depowering ... just give you too much lee helm.

That rope out the to tack is bad because it tends to overtwist the sail - this will lead to unstable downwind handling as the sail twists too much. Particularly when running or broad reaching. Come to think of it .. it may tend to overpower the front of the sail and twist off a depower the back part ... this might mean that in a gust ... instead of the back of the sail moving out that the front does it instead. I can't say that IS what happens but it is a bit more probable with tension in the rope out to the front of the boom.

So instead of the rope to hold the boom there are a couple of ways. Part of the problem might be that the downhaul was not tight enough. When the boat is overpowered you need outrageous tension in the downhaul. I think the others have covered that.

Now to stop it sliding forward ...

One way is instead of taking the downhaul over the top of the boom attach a block to the right position using the same loop and cow-hitch method as on the the other blocks. Or you could use the rope over the top of the boom but put a thumbcleat or a small deadeye to stop the boom from moving forward. It is best if the screws to hold the deadeye or thumbcleat is on the top of the boom. That way the area of the boom the holes are in is in compression.


http://farm5.static.flickr.com/4055/...a0712b4a6a.jpg

Screws do weaken a piece of timber loaded in tension but don't weaken one loaded in compression at all. Providing the screws stay in the holes.

Best wishes
MIK

Originally Posted by Joost

I have not singlehanded her much (my girlfriend being very keen on sailing as well), but I would rather put in a reef than adding ballast and overcomplicating the boat.

The hull is very easily driven and in my experience a reef hardly makes a difference to the boat speed (because otherwise when not putting in the reef you would have to spill the wind anyway half the time).

Just my 2.

Best regards,

Joost

Callsign222 - Thank you very much for sharing your experience with us. Lots of good comments and advice on sorting the rig and reefing for heavier conditions.

I agree very much with Joost's coments above, and think that water ballast is the wrong way to go – lots of complication and weight and potential for things to go wrong, especially sailing with a middle seat compartment half full of water.

I think we are all tending to take our experience and preconceptions from sailing racing dinghys – lasers, 420’s, 470’s … and apply them to the Goat, whereas Mik has thought out the Goat in quite different and entirely good ways.

In any of these racing dinghies, you have a tall high aspect rig and you can’t reef it, or even if you set it up so you can the COE moves in bad ways as you radically reduce sail.

To compensate for these deficiencies, you have lots of fancy sail controls – down haul, outhaul, boom vang, cunningham, bendy mast… and do lots of fiddling and heaving on lines to depower the sail by flattening it as the wind increases. On the wind in heavier conditions you’re hiking out white knuckled and luffing in the gusts to spill wind. The luff of the sail is flapping and the rudder is stalling with all the weather helm from too much heel. It feels like you’re going fast.

However, if you have a boat which can be efficiently reefed, there’s another way – reduce sail area quite radically so the power in the sail is about the same as in the lighter conditions. Good things now are you have just as much driving force as before but the COE is much lower so heeling moments are much less and the boat stays nice and upright. You can trim what’s left of the sail for good lift to drag ratio and lots of power low down. Centreboard half way up, but never all the way up, so heeling moment is less. Lift from half the centerboard will be the same or more as before due to the speed.

You can get to the point where you’re screaming along with the boat flat and planing, your bum on the seat, your fingertips on the tiller and a huge grin on your face.

There’s a good example of this on Ross Lillistone’s website with his Periwinkle in heavier conditions – the skipper has just the mizzen stepped in the middle mast position, so about 50 square feet of sail versus the full rig of 155 square feet. He’s on his own in strong winds in a light 17 by 5 ft boat and he’s relaxing on the seat. The interesting thing is the boat in the background with a big full battened main plus jib and two heavy fellows hiking out as hard as they can – but the singlehanded boat with the 50 square foot balance lug is overtaking them.





Same principle applies to the Goat, even more so as it’s half the weight again on almost the same waterline length so should drive even easier and faster with reduced sail in stronger winds.

We also need to understand that reefing small boats while underway singlehanded and conditions have made it necessary isn’t going to be successful without some serious thought and preparation/practice to make sure things work. The balance lug rig is easer to drop and reef than other rigs, but the mast and clew/front of the boom are a long way forward. The boat will be unstable if you go any further forward than the middle seat on your own, so you need to be able to release and refasten the halyard from back there, you need to be able to crank on Mik’s “brutal” downhaul tension from back there once the sail is back up, you need reefing lines already threaded from the clew up to the reefing eyelet on the sail luff, back down to a cheek block on the front of the boom, then back to a cleat near the middle of the boom so you can pull the reef in at the front without going forward. The rear attachment could be left simple with a couple of pieces of line in your lifejacket pocket you can pull out when needed.

You also need to be able to keep the boat head to wind while you’re doing all this. Maybe there’s a point in the boat you can sit so the bow is down and the stern up so the boat stays into the wind, but not so far forward that stability is reduced. If that doesn’t work, some sort of quick deploy/retrieve sea anchor might be the story. More on this soon.

Alternatively, make sure you have some oars on board, and restrict your solo excursions to places upwind of an easy landing/sheltered point so you can always drop the sail and get blown downwind to somewhere safe if you get overpowered/and/or see that you've reefed very conservatively before you leave the shore. I imagine the GIS will make quite good way downwind without the sail up if it’s blowing as it’s so light and the sides are high.

Ian

A good continuation to the conversation Ian, thank you for contributing!

Much to my surprise, when I was re-tensioning my reefing points to keep the sail underneath the batten (and yes Mik, I was also looping a line around the sail to keep it under control) I had steerage speed under just bare poles. There is so much available hull surface and so little of the boat in the water (me alone, little gear) we were moving along. It was kind of neat.

There is definitely a spot on the boat where we can sit, reef the new tack, and stay stable, I just have to go find it, but it obviously exists. Sitting next to the mast on the forward seat solo is not advisable. I'm kind of wary of overcomplicating the rig to make things easier to reef from the stern, because the rig is so beautiful in its simplicity-- but that's a personal choice and decision. A line on the Wooden Boat forum recently has been "Simple does not mean easy" and I'm looking foward to finding a simple solution to a simple boat. Again, a personal choice.

More discussion on ballast. Watermaat was discussing water ballast in his central compartment, but as Ian mentioned, too complicated. What about two 50lb bags of sand or other dry material next to the centercase?

Hello Ian,

Very good discussion indeed!

You have very eloquently described my way of thinking and approach with the Goat since I have had her in the water. Last year's Raid Caledonia in Scotland (we participated after only having sailed the GIS for five days) taught me that she goes just as fast, if not faster, reefed when the winds are too strong to handle the full sail area.

Since I have windsurfed a lot, it was not as much a revelation to me as using smaller sails when the wind gets stronger is very normal in windsurfing.

Callsign222,

Sandbags would make the Goat's movements slower and more docile. Personally I would however prefer to reef rather than to put additional weight in the boat.

Best wishes,

Joost

Originally Posted by callsign222

There is definitely a spot on the boat where we can sit, reef the new tack, and stay stable, I just have to go find it, but it obviously exists. Sitting next to the mast on the forward seat solo is not advisable. I'm kind of wary of overcomplicating the rig to make things easier to reef from the stern, because the rig is so beautiful in its simplicity-- but that's a personal choice and decision. A line on the Wooden Boat forum recently has been "Simple does not mean easy" and I'm looking foward to finding a simple solution to a simple boat. Again, a personal choice.

Hello Callsign222,

It would be best to keep your centre of gravity as low as possible when reefing and sitting in the front of the boat: in other words, better to crouch down on the floor aft of the mast than to sit on the forward seat next to the mast. You can also easily slide the boom and yard back a bit in the boat when the sail is down to work on setting the reef.

The simple approach works quite well in my opinion: I have a snap hook (or whatever they are called) tied to the front part of the boom allowing me to "hook" the reef's front eyelet easily and quickly and a piece of rope going the reef's back eyelet to tension the foot of sail. Work's a treat so far.

Best regards,

Joost

Excellent discussion.

As far as head to wind ... I didn't find it so necessary with Beth (I have reefed her a lot) or sail lowering and raising on the Goat. It does help a lot if the sail is on the lee side of the boom. Push the tiller to leeward hard. Wonder if a velcro tie would make sense?

That way as soon as the boat gathers any way it points up and luffs the sail. The drag on the sail will then pull the bow off the breeze so the sail fills again, the boat starts moving a bit again and luffs.

I think head to wind without the mizzen would be very difficult to achieve as you would never know which way the bow was going to blow off the breeze.

When hoisting the sail it is very important to ease off the downhaul before you hoist the sail. Then hoist the sail. Pull on the downhaul and you are sailing. If the downhaul is not loose enough it adds a lot of time and difficulty to sail hoisting. The more I read and think about it the more I think it makes a LOT of sense to have a halyard and downhaul that can be handled from the mid seat when singlehanded.

This could be either leading it right back to the centrecase along the floor or fitting two CL217 clam cleat on the back edge of the front seat (not so good if someone needs to sit there often when the mast is not in)


This cleat allows the halyard and downhaul to be pulled out of the cleat completely for quick drops of the sail or to get rid of downhaul tension completely.

MIK

Originally Posted by Boatmik

The more I read and think about it the more I think it makes a LOT of sense to have a halyard and downhaul that can be handled from the mid seat when singlehanded.

This could be either leading it right back to the centrecase along the floor or fitting two CL217 clam cleat on the back edge of the front seat (not so good if someone needs to sit there often when the mast is not in)


This cleat allows the halyard and downhaul to be pulled out of the cleat completely for quick drops of the sail or to get rid of downhaul tension completely.

MIK

What I was quite pleased with Mick, was the ease with which I could adjust my downhaul from my position just aft of the mid seat. I'm still planning on moving this control to the mid seat though. As you can see, I have the cleat raised on a wedge and the line is long enough to just reach down and adjust from the mid seat position, because the cleat has a built in fairlead. But I do have to reach down to do it, and if things are really rough it might be hard.

Attachment 140181

The halyard however, has a lot more force on it than my downhaul which is reduced by 4:1, so the fixing to the mast step needs to be very capable of bearing the full load. I am thinking along the lines of attaching a screw-in eye, with maybe a 6mm thread or close to it. However, I will need to cut it shorter so that it doesn't go right through the step! To fix it in, maybe a 10mm hole filled with epoxy glue mix and set it in? Do you think that will handle the load OK?

However, this will make the sail quite difficult to hoist from the side of the boat on the shore won't it?

I would use a trick they sometimes use on larger boats.

They sometimes put two cleats in line ... one in the existing position or on the side of the mast ... so you hoist and cleat. Then you take up the slack for the continuation of the rope where it cleats near the centrecase. Then you flip it out of the first cleat. The trick is to use the CL217mk2 Ior next size up CL217Mk1 - check the operating rope diameters) or a CL222 (maybe the next size up from the 222 as it will only handle 4 or 5mm rope) as the cleats that are closest to the mast and have the one closest to the mast slighly out of its natural line to the second cleat so it won't recleat when you flip it out.

Don't be tempted to use the plastic alternatives they just don't last. You want the aluminium ones - which will last a few years before needing replacement.

The other way is to have only one cleat beside or on the centrecase but have a pulley behind it. That way you can pull the halyard from any location behind the mid seat pulling it through the cleat ... the cleat in this case is ON the natural line of the halyard. But still need to use a CL217 with the open side so the halyard can be completely released from the cleat.

As far as the screws go ... use metal threads and glue them in with thickened epoxy They will hold well providing you wash the metalthreads in clean acetone and dry them before they go in. The mast step is quite thick so there will be plenty of bonding area for long metal threads.

Metal threads are way stronger than any type of screw - as it is quite possible to rip the head off a screw with a cordless drill, but very unlikely to do the same with a metal thread.

MIK

OK, that sounds like a good way to go, and simple enough too. Thanks.

With the metal threads in the mast step, I epoxy them in by themselves, or attached to their nuts?

Epoxy straight into the wood using a runny glue mix. use a pipe cleaner or something like that to load up the hole with the epoxy, Clean the metalthread in acetone and put on some clean rag or tissue to dry off - dip into the epoxy and drive them in.

I do this with any high load fastening. It does mean you have to heat them to get them out again (but will you ever have to?). If it is a low load and loaded in shear as per most fittings you can just use varnish in the screw hole or on the screw.

But here it is high load AND a direct load that will tend to pull the screws out so epoxy is the best way.

Best wishes
Michael

Ok guys, I just got home, picked up my sail with the new reef points, quickly adjusted my downhaul, and went sailing, solo.

Force 1 and 2. Unfortunately light winds, so I went with all 105 sq. feet flying. Mostly I sat on the floor, but a few times I had to sit up on the rail, and twice I had to to dump the sail to keep from going over.

Hoisting the sail at sea, I sat on the front of the daggerboard trunk and propped the boom on my shoulder. This kept me centered, back from the front seat, and also gave me the ability to either shift my weight right or left depending on the wind and where the boat wanted to go.

My downhaul has also been reconfigured. I still need addition power, but this was the hardware I had to work with, and this was the best I could come up with. You can see in the picture. Still not enough downward force, this picture was taken running on a port tack back to the beach. Throughout the past 2 hours beating against the wind, the boom slowly inched forward, you can see how the downhaul is not parallel to the mast. Also, notice that the tack tiedowns have stretched, and the stretch on the first zip tie, all from the downhaul tension. A small factor is that the I had to re-rig the spars after getting the sail back from the sailmaker, and I didn't get enough tension on the tie-downs. So those will be re-tensioned, the first grommet will get an extra tie-down (until I tie down the entire foot--- line has yet to come), and I need to hunt around for a better downhaul arrangement with one more level of purchase. Marine hardware (blocks and such) is a drive from here.

That being said, this medium-force downhaul significantly improved my ability to depower the sail-- PHEW. There is no question that Mik hit it straight on, my line to the front of the boom was preventing the sail from quickly and efficiently depowering though some sort of twisting action. This was noticeable. The increased downhaul tension also for the most part kept the rig in place, and this was noticeable too.

Other than that, the boat was well behaved and I was happy. I'm looking forward to getting back out in some force 3 and 4's and more and seeing what she can do. I can't wait to get her on a broad run up on plane!

More reporting to come as I sail more. So far, so good!

Cool.

Sounds like you are getting the hang of it.

When single handing I usually sit on the mid seat when I am not needed on the gunwale. It is a bit easier to slide in and out to balance the boat (I find).

Going downwind in light winds I often stand. If I had a pipe I would smoke it. I think a parrot and a tricorn hat would be overdoing it just a tad too. But if I had a long way to go I would probably be on the cockpit floor too as close to the mid seat as I can get.

Sounds like the problem is the downhaul is creeping backwards as you sail the boat around. The thumbcleat would solve that.

I think someone had noticed that the ratchet block doesn't get a lot of wrap when you sit on the cockpit floor. Ie the sheet is only deflected slightly by the ratchet block. In light winds this is OK. Also downwind the sheet loads are quite light.

In stronger winds you will have to be on the side, but if the small change of sheet angle around the ratchet block seems to reduce the friction available then you can put the ratchet block as the one on the boom before it goes to the cockpit floor and thence to your hand. That should ensure the sheet is wrapped around at least 90 degrees so the friction system will work.

I have meant to mention that for a while.

MIK

I did a lot of standing in the Laser, and I love standing in the Goat, it's got such a spacious floor I can stand anywhere. I could have a ballroom dance competition there! In light winds it helps me keep the boat mostly flat but with just that little bit of heel to stop the slapping. I like to keep my tiller extensions long for this purpose.

I like sitting on the floor next to BH3. Remember I'm really tall, so I can prop my legs up on the opposite side of the boat and it's like I'm in a Laz-y-Boy! Very comfortable, the angles of the boat are perfect for my stature.

I haven't figured out what I'm going to do with the ratchet block yet. When hauled in and sitting on the floor I get only a small percentage on the ratchet, but if I'm on the floor its obviously light winds, so no problems anyway. I think about putting it on the boom, but haven't decided yet.

In light winds I also switch the ratchet "off", so I can play the sail out easier when ghosting along.

What pipe would you choose from my collection?

Originally Posted by Boatmik

When single handing I usually sit on the mid seat when I am not needed on the gunwale. It is a bit easier to slide in and out to balance the boat (I find).

MIK

I quickly found the mid seat was my spot too, even if Kim was on the other side. By myself I could stretch out with my feet on the opposite inwale for a quick push off onto the gunwale when a gust arrived.

By the way Christophe, I agree with Mick that your downhaul is slipping back and this is causing your boom to push forward. Your single loop over the boom just won't stop it from doing that. For now, I would put a double cow hitch around the boom 400mm from the tack and tie your downhaul to that. I too have a box shaped boom and the double cow hitch doesn't move at all. Keep the loop small and as tight against the boom as you can.