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BigCat
12th October 2009, 02:05 AM
I just happened upon something new: A cat with a stayed Balestron rig. The cat was designed by Kurt Hughes, and built in NZ. I don't know whether the rig was the idea of Kurt or of the owner, but it's always fun to see something new in the way of rig design. It will definitely help the morale of those who have a neurotic dependency on stays and shrouds, but would like an easily handled rig. It might also save some weight, at the cost of some windage and monetary expense. The familiar pointy headed sails will also encourage those whose herd instinct keeps them close to their fellow wildebeests, though it is a less aerodynamically efficient profile shape than an ellipse.

http://www.southseasailing.com/News.html

Talbot
12th October 2009, 09:39 AM
I do not much like the look of that stayed rig. the stays must connect to bow and stern of each hull (from the angles) thus there must be a significant bending motion imparted to the foot of the mast trying to force the mast through the hull and to fold the hulls inwards.

I can only presume that the tension requirements of this rig are significantly less than a normal rig and are used to reduce the mast size and weight, but still provide sufficient strength for the rig.

BigCat
12th October 2009, 05:15 PM
I do not much like the look of that stayed rig. the stays must connect to bow and stern of each hull (from the angles) thus there must be a significant bending motion imparted to the foot of the mast trying to force the mast through the hull and to fold the hulls inwards.

I can only presume that the tension requirements of this rig are significantly less than a normal rig and are used to reduce the mast size and weight, but still provide sufficient strength for the rig.

There are two forestays and two backstays, one stay to the front and near the back of each hull. I believe you must mean compression rather than bending force at the foot of the mast. There is also a system of jumper stays, both forward and aft, to keep the mast in column, that attach the mast to itself. The aft jumpers are made possible by the fact that the mast rotates, thus keeping the mainsail off of the aft jumper struts. I have described the conventional stayed mast as a bow and arrow, with the mast as an arrow that the stays are trying to force through the boat. This rig is no different than any other stayed rig in that regard. The foresail does not attach to the forestays that hold the spar up, and that is a difference between this rig and the usual Marconi rig.

Talbot
12th October 2009, 05:55 PM
Yes I did mean mast compression, leading to bridgedeck bending - but shortened it all in my head, and ended up with mast bending:eek:

I would suppose that those stays are under a lot less tension than would be required on a marconi rig, as the real forestay tension would be part of the rigging integral to the mast.

BigCat
12th October 2009, 06:02 PM
Yes I did mean mast compression, leading to bridgedeck bending - but shortened it all in my head, and ended up with mast bending:eek:

I would suppose that those stays are under a lot less tension than would be required on a marconi rig, as the real forestay tension would be part of the rigging integral to the mast.

They are also very widely spread out - the tension goes down as the angle at which the stays meet the mast gets bigger. The four stays meet the mast at a much greater angle than shrouds usually do. As you say, you aren't using the tension in the support system to control sail draft, so no extra tension there.

BigCat
12th October 2009, 06:28 PM
I do not much like the look of that stayed rig. the stays must connect to bow and stern of each hull (from the angles) thus there must be a significant bending motion imparted to the foot of the mast trying to force the mast through the hull and to fold the hulls inwards.

I can only presume that the tension requirements of this rig are significantly less than a normal rig and are used to reduce the mast size and weight, but still provide sufficient strength for the rig.

If you right click on the photos on the website ( http://www.southseasailing.com/News.html ,) and select view image, you will find that the photos are a lot larger than their appearance on the website would lead you to think. You can see the details much better that way.

Illusion_Reality
28th October 2009, 03:55 PM
I've seen this rig on an home built steel monohull in Annapolis. The owner hadn't had a lot of experience with it then, but I saw him again in Charleston, SC . He was less than pleased with it and had plans of putting a bermuda rig on to replace it.
Mike

BigCat
28th October 2009, 04:51 PM
I've seen this rig on an home built steel monohull in Annapolis. The owner hadn't had a lot of experience with it then, but I saw him again in Charleston, SC . He was less than pleased with it and had plans of putting a bermuda rig on to replace it.
Mike

"This kind of rig." What kind of rig? The devil is in the details, and steel is very heavy. Perhaps he does not have enough sail area. He certainly didn't have a biplane rig unless he has a catamaran, and a steel catamaran is such a bad idea that no one who knows anything about boat design would propose one. The rig may not have been competently designed, whatever kind it may be. Failure, for example, to position the rig correctly in its fore and aft placement can completely screw a rig up.

Illusion_Reality
28th October 2009, 05:08 PM
"Balestron rig" or aerorig which is what his was. His was unstayed. I would prefer unstayed. The mast having to rotate on a bearing plate held by four stays goes against my "more moving parts more headaches" mantra.
Mike

BigCat
28th October 2009, 05:24 PM
"Balestron rig" or aerorig which is what his was. His was unstayed. I would prefer unstayed. The mast having to rotate on a bearing plate held by four stays goes against my "more moving parts more headaches" mantra.
Mike

Of course you'll get no arguments in favor of stayed rigs from me! It would be hard to get enough sail area for the weight of a steel yacht on a Balestron rig. If he changes to a standard marconi rig, he can sail with gennoas, and get more sail area. Of course, he may not be so happy with his boat then either. What you really know is that he isn't happy with his boat, and that he blames the rig.