Why do I have a Mizzen?

[Richard5]

[QUOTE=DefinitelyMe;1267897]All that weight aloft does atrocious things to your angle of vanishing stability - reduced by about 15 degrees! If you should ever have the misfortune to become inverted you've now got a huge, heavy keel keeping you there./QUOTE]

I, having zero experience with in-mast furling, ask that you provide further explanation. Especially what is this "vanishing stability"? Color me curious.

[zeehag]

i have watched as folks with brand new boats with im mast furling furl their main into the mast--it takes forever, and gets stuck in flat water--i couldnt believe folks actually try to cruise with that...but then i saw boat is for sale.......i understand why. they made it to mazatlan and done.

gaff rigged sloops have booms that overhang the transom by many feet. in weather, as with marconi, event he best drop and stow the main altogether.

challenge to disbelievers--sail a sloop somewhere dfor year.
comeback and sail a ketch on that same path you sailed in the sloop.....then report back as to which boat you enjoyed sailing more.
make sue someone who knows how to sail each properly is with you.
there must be heavy weather involved in both sailing trips. make it off florida.

[IdoraKeeper]

Was out to in a real good blow in April....sailed under mizzen and Yankee. It has a civilizing effect on otherwise dicey conditions. There was a great deal of thought put into these old design rigs. Mine allowed me to enjoy the day while newer rigs thrashed and struggled to reef. That said, I am a cruiser not a racer.

Todd

[zeehag]

Originally Posted by IdoraKeeper

Was out to in a real good blow in April....sailed under mizzen and Yankee. It has a civilizing effect on otherwise dicey conditions. There was a great deal of thought put into these old design rigs. Mine allowed me to enjoy the day while newer rigs thrashed and struggled to reef. That said, I am a cruiser not a racer.

Todd

EXACTLY!!!!!!!!

[Nicholson58]

Originally Posted by DefinitelyMe

Having the mizzen has several advantages:

1) It allows you to balance the boat more effectively as you have more choice of where to place your center of effort (the average of the forces produced by your sail) in relation to the center of lateral resistance (the average of the forces generated by your keel and rudder), which allows you to sail more efficiently on any given point of sail (except upwind, where sloops generally have the upper hand).

2) It lowers your center of effort. Ketches (and yawls, but less-so) can generally have shorter masts compared to a sloop with the same sail area. What this means is 1. Your rig is inherently stronger (because the horizontal component of the force on your shrouds / chian plates is greater owing to the more acute angle of the shrouds with the deck) and 2. Because the average of the forces acting on your sail is lower down you will have less heeling moment.

3) It breaks up the sail area into manageable chunks, which is great for short-handed sailing. It also makes it much easier to reduce sail area in a hurry when the breeze picks up; something that if often a pain the arse for sloops with big slab-reefed mainsails. Consequently a lot of people will reef the jib (because it roller-furls) when they should really be reefing the main, and this leads to poor performance and an unbalanced boat.

As previous posters have said, try sailing under mizzen and jib alone in anything other than a very light breeze. If you're under full sail, the breeze picks up and you start to get weather helm, flatten the sails first with the vangs, halyards and outhauls and if it's still a problem ease the mizzen sheet a touch or better, go down on the traveller if you have one.

I'm confident that in time you'll come to love your ketch.

All good points. Also, it give you a place to hoist the Mizzen staysail. We get a lot of boat speed added on the low end conditions but the 12 apparent & up results in too much helm. It is more useful off the wind and is no use close hauled. My only real problem is the mizzen boom takes the real estate needed for solar panels and the dinghy.

[IdoraKeeper]

Lovely boat. Idora is rigged for stay sail but it was not onboard when I bought her. Its on the list of must do stuff.

Todd

[Richard5]

Originally Posted by zeehag

i have watched as folks with brand new boats with im mast furling furl their main into the mast--it takes forever, and gets stuck in flat water--i couldnt believe folks actually try to cruise with that...but then i saw boat is for sale.......i understand why. they made it to mazatlan and done.

gaff rigged sloops have booms that overhang the transom by many feet. in weather, as with marconi, event he best drop and stow the main altogether.

challenge to disbelievers--sail a sloop somewhere dfor year.
comeback and sail a ketch on that same path you sailed in the sloop.....then report back as to which boat you enjoyed sailing more.
make sue someone who knows how to sail each properly is with you.
there must be heavy weather involved in both sailing trips. make it off florida.

I have decided you're on a smart phone. Do you proofread what you write, or, you did proofread and this is as good as it gets. Iphones and the like must be the bain of English teachers everywhere.

I slay myself. har har

Otherwise, you have a great idea about sailing different rigs over the same course.
You want heavy weather in the states? I suggest Pt Conception 'tween Feb and April. That's on the west coast, yeah!

[zeehag]

Originally Posted by Richard5

I have decided you're on a smart phone. Do you proofread what you write, or, you did proofread and this is as good as it gets. Iphones and the like must be the bain of English teachers everywhere.

I slay myself. har har

Otherwise, you have a great idea about sailing different rigs over the same course.
You want heavy weather in the states? I suggest Pt Conception 'tween Feb and April. That's on the west coast, yeah!

richard, i understand your need to be a wiseguy, but i am disabled with bad hands and poor interweb signals. i get complaints every few years. i am on a netbook in my boat.
i know all about heavy weather in west coast as i am now on mexicos costa alegre with a beautiful td/ts forming on our shoreline, and predicted 5 metre seas which could have some impact on our lagoon here. i enjoy sailing my ketch in prefrontal winds, as they are strong and i have the boat for it. wind is good. with a sloops i do not enjoy sailing prefrontal winds nor chubascos..is a lot more difficult to manage the boat and it is not comfortable.
in my ketch, i can still cook food on my stove and enjoy life in comfort. there is a reason for the continuing existence of these split rigs.
i sail a ketch in winds over 20 kts whenever possible.
i have sailed gom in storms IN A SLOOP--is as heavy as some of these souls can figure out, so is no need for death--just practice..lol


and i would not have a smart fone if it was gifted to me with 10 years unlimited service world wide. thankyou......rodlmao

[Richard5]

Zee, I have been aghast at my insensitivity since I posted that. My heart has been heavy to think I had caused even a slight offense to you. Your response is more generous than I had imagined. You are correct, I was some kind of a wise guy, at the time I thought I was being funny. You have my most profuse apologies. You have my thanks for being so kind, especially when confronted with my brusque behavior.

[sparau]

Originally Posted by Richard5

Do you proofread what you write, or, you did proofread and this is as good as it gets. Iphones and the like must be the bain of English teachers everywhere.

he he - do you mean bane? Never heard of bain...

Gotta love it when people do that

[zeehag]

because my typing is a matter of jokes and a new language, it is always fun to welcome folks who dont understand why i cannot typo, aside from getting a D in it in 8th grade and saying i wasnt gonna rule the world anyway, so i may as well try something less repetitive for learning, like nursing....lol....which, i may add, is easierto learn...
i can fix a human body but i cannot typo--so much for me ruling the world.....lol

[DefinitelyMe]

[QUOTE=Richard5;1267922]

Originally Posted by DefinitelyMe

All that weight aloft does atrocious things to your angle of vanishing stability - reduced by about 15 degrees! If you should ever have the misfortune to become inverted you've now got a huge, heavy keel keeping you there./QUOTE]

I, having zero experience with in-mast furling, ask that you provide further explanation. Especially what is this "vanishing stability"? Color me curious.

The angle of vanishing stability is the agle of heel at which a boat goes from having a positive righting moment to a negative righting moment. Picture a boat sitting upright. It takes very little force to induce a small amount of heel. However, as the boat heels further the force that is trying to right the boat increases and increases, let say to about 60 dgrees of heel. This is about average, and is a combination of the force of your keel (which is now sticking out at a 60-degree angle) and the buoyancy produced by the side of the boat that is in the water. Conversely, the weight of the mast (and any other part of the boat that is higher than the centre of buoyancy) is having the opposite effect - trying to heel the boat further.

Beyond about 60 degrees the force attempting to correct the heeling moment decreases, but it is still positive up to about 120-degrees for your average modern sailboat. That means that if you were to heel that boat over 120-degrees (so that the mast is sticking into the water) it would still right itself and pop back up once the force that put it there in the first place is removed. But what happens if you make the mast heavier? Well, that extra mass is going to increase the tendancy for the boat to invert. Imagine trying to hold a PVC pipe in your hand horizontally. Now try it with steel pipe. That pipe wants to go down and hang vertically from your hand, and it's just like that with your mast.

The attached picture is a good diagram that i found on sailtrain.co.uk. RM stands for 'righting moment'. Notice that beyond the angle of vanishing stability, the righting moment is actually acting to keep the boat inverted. Fortunately, the kinds of conditions that are likely to roll a boat sufficiently that it becomes inverted are also likely to provide enough force to roll the boat from an inverted position back past the angle of vanishing stability so that it rights itself once again.

[Jammer Six]

It took the picture showing the two centers of gravity in Cole (and a couple nights pondering it) before I understood righting moments. (And when I say "understood", I mean that now I only have to think about it for two or three minutes before I get it right.)

[maersi]

I used to sail sloops, then I accidently bought a ketch - everything else about the boat was right, I thought I could live with two masts.

Now, I would never go back to a sloop. My perfect rig is a cutter ketch - so many sails to play with. Zee, I loved rodlmao, with your permission, I will use that in future ;-)

[Hudson Force]

If I wasn't so pleased with my ability to clear a number of fixed 55' bridges with my 41' ketch, I'd probably select a cutter as the best cruising rig. Regarding the in mast furling systems, I've never had one, but I've seen and been aboard many that use them with great ease and success. I've got nothing against them except the obvious compromises that we make for every advantage.