To All Those Who Twizzle

[Sabbatical II]

In fitting out a new medium to heavy displacement cutter rigged sloop, I am trying to give myself redundancy and options with the sailplan. The roller furling headstay comes with a standard 135% genoa and twin foils. I think I also want a smaller yankee when I'm inshore so that I have the option of a sail that will tack a bit easier around the inner stay. What I want to know is, Can I twizzle with these unequal sails or would that unbalance the boat?

Greg

[Unicorn Dreams]

Twizzle?

[GordMay]

Originally Posted by Eleebana

... Can I twizzle with these unequal sails or would that unbalance the boat?
Greg

No, and yes.

See the discussion ➥ http://www.cruisersforum.com/forums/...rig-29360.html

And ➥ http://www.bethandevans.com/pdf/twizzle%20rig.pdf

[Bash]

The reason a twizzle rig works so well to reduce roll is that the center of effort of the sails is so much lower than that of a spinnaker. This assumes, of course, twin genoas. Substituting a yankee for one of the genoas would work against this principle. Additionally, the yankee would be more difficult to pole out because of the high clew. Putting a pole that high up would certainly not add to stability.

A far better solution would be to find a sail to twin with your existing genoa.

[Paul Elliott]

Originally Posted by Bash

The reason a twizzle rig works so well to reduce roll is that the center of effort of the sails is so much lower than that of a spinnaker. This assumes, of course, twin genoas. Substituting a yankee for one of the genoas would work against this principle. Additionally, the yankee would be more difficult to pole out because of the high clew. Putting a pole that high up would certainly not add to stability.

A far better solution would be to find a sail to twin with your existing genoa.

True, but twin headsails are also more stable than a spinnaker because they are secured to the headstay and can't rotate from side to side as the spinnaker does. The spinnaker is inherently unstable, while twin headsails are inherently stable. (Not that you still can't get yourself into trouble with them!)

With mismatched twin headsails the boat won't be as balanced, but I think it will still be more balanced than (for example) when using a wing-and-wing (jib on one side, main on the other) configuration. Depending on the sizes of your yankee and your main, you may lose power with the twins, but the downwind stability may be better. Instead of using a second pole, the angles might be better if you use a block at the end of the boom to hold out the yankee sheet.

We spent a couple of days with unequal twin headsails a few years ago, and the ride was great. The sails were both Genoas, but one had a higher foot/clew than the other (one was practically a deck-sweeper, and the other was cut high for visibility). The difference in area probably wasn't that significant though.

The true "twizzle" or "twistle" rig uses a free-floating pole between the twin headsail clews. Most people (well, I) use twin mast-mounted poles or the pole/boom arrangement instead.

I wouldn't be afraid to try the genoa/yankee configuration. You might be pleasantly surprised. Or it might suck. What's the worst that could happen???

[Sabbatical II]

Thanks for all the info. Next question. How much does a permanent inner forestay complicate issues with the Twistle rig?

Greg

[islandplanet]

We're building a set of twins for a customer that is using a Twizzle rig. I'm looking forward to going out on the boat to see how it works out. The customer has a used set of twins with a common luff that is a bit short on the leeches but it allowed us to play around a bit at the dock with it.

The weakest point of sail for most cruising boats is deep downwind. Contrary to popular belief assym spinnakers are more of a reaching sail than a downwind sail although they can be optimized best as possible for downwind. Generally getting to a downwind destination is going to involve jibing. The best sail for deeper downwind angles is a conventional spinnaker but most people understandably don't want to deal with poles and spinnaker wraps.

We run a large twin headsail arrangement on our Amel ketch and the boat is very fast even dead downwind. There's some hardware and special fittings involved that would be tough to duplicate on some boats. We crossed the Sea of Cortez so quickly with our twins that I was working hard to keep the boat slowed down to permit a daytime arrival in Mazatlan.

[islandplanet]

Originally Posted by Bash

The reason a twizzle rig works so well to reduce roll is that the center of effort of the sails is so much lower than that of a spinnaker. This assumes, of course, twin genoas. Substituting a yankee for one of the genoas would work against this principle. Additionally, the yankee would be more difficult to pole out because of the high clew. Putting a pole that high up would certainly not add to stability.

A far better solution would be to find a sail to twin with your existing genoa.

Perfectly stated. And if the primary genoa is on a furler that has a second groove there's the possibility of building a second sail to feed in the extrusion. The only drawback of course is you can't furl it. It's possible to rig it so you can furl with some sort of halyard lock that takes the halyard out of the equation. Naturally if you raised both sails from the top swivel, furling both becomes possible.

[Dockhead]

Originally Posted by islandplanet

The weakest point of sail for most cruising boats is deep downwind.

Not our boat. Dead downwind or nearly dead downwind in anything over 15 knots of wind, our boat will break hull speed with just the yankee alone, and is extremely stable in that configuration. In 20 knots or more of wind in that configuration we can make double digit speeds over hours at a time with hardly any effort. You just have to be careful not to sail more than say five degrees by the lee, or the sail will start to collapse. But even that is fairly benign, even in high winds, nothing like dealing with a preventered-out mainsail.

We never bother with the mainsail in more than 10 knots of wind, when sailing downwind.

I suspect many cruising boats are similar.

Here we are in 40+ knots of wind, on our way to doing 55 miles in less than five hours. The autopilot is set to wind-following mode and we're just relaxing in the cockpit, listening to Mahler and drinking beer, in complete comfort:

http://www.youtube.com/watch?v=-4vMA6SMGgs

Yes, we had to jibe a couple of times, and one leg of the trip was not downwind (and that part was hard).

[Bash]

Originally Posted by Eleebana

Thanks for all the info. Next question. How much does a permanent inner forestay complicate issues with the Twistle rig?

One of the things many people don't realize about the Twizzle rig is that you can actually go to weather without having to drop one of the sails. Once you release the sheets from the whisker poles, the windward sail will tack on top of the leeward sail, and the leeward sheet will control both sails. Granted, this is not an ideal sailing arrangement, but it can be awfully handy in certain circumstances.

An inner forestay, unfortunately, removes this option.

[islandplanet]

Originally Posted by Dockhead

Not our boat. Dead downwind or nearly dead downwind in anything over 15 knots of wind, our boat will break hull speed with just the yankee alone, and is extremely stable in that configuration. In 20 knots or more of wind in that configuration we can make double digit speeds over hours at a time with hardly any effort. You just have to be careful not to sail more than say five degrees by the lee, or the sail will start to collapse. But even that is fairly benign, even in high winds, nothing like dealing with a preventered-out mainsail.

We never bother with the mainsail in more than 10 knots of wind, when sailing downwind.

I suspect many cruising boats are similar.

Here we are in 40+ knots of wind, on our way to doing 55 miles in less than five hours. The autopilot is set to wind-following mode and we're just relaxing in the cockpit, listening to Mahler and drinking beer, in complete comfort:

Yes, we had to jibe a couple of times, and one leg of the trip was not downwind (and that part was hard).

I think your boat is an exception rather than the rule. We've watched countless boats motor all over Mexico because they lacked a good light air downwind sail arrangement. Almost every boat sails well with working sails in 15-20 knots but unfortunately we don't always have that much breeze.

[skipmac]

[QUOTE=Dockhead;620474]Here we are in 40+ knots of wind, on our way to doing 55 miles in less than five hours. The autopilot is set to wind-following mode and we're just relaxing in the cockpit, listening to Mahler and drinking beer, in complete comfort:
[QUOTE]

If I may ask, what model autopilot are you using? Wind following mode sounds interesting.

By the way, I would have chosen Bach with a gin and tonic.