Is it just my imagination ?

[MaryEllaRose]

We've just made the switch from a Catalina 22 to a Catalina 25 wing keel, partly due to "Three-Footitis" but also in search for a more stable boat. We're very much the fair weather sailors, keeping to the southern end of the Detroit river and the western end of Lake Erie. We're most comfortable in light winds, not exceeding 8 to 10 knots, waves 1 - 2 feet.
It seems to me that the Cat 25 rolls and pitches much more in the same wind / wave conditions. I know the Cat 25 has a higher center of gravity since it's a larger deeper boat than the Cat 22 but I assumed it be a more stable ride....
Is it just my imagination?

Tom G

 

[Will Gilmore]

Rolling is a function of cross sectional shape - width, dead rise, roundness of chine, height of center of gravity and, in light weight boats, rigging height and weight, giving a longer swinging moment up high.
Boats built like logs with a keel will roll a lot (think trawlers with heavy high cabins and masts). If they are narrow and fitted with large keels that present a broad profile to resist that roll and lots of weight down low, little or no rolling even on the side of a wave. They are like Weebles. Then there are boats who's hull cross section has inherent stability, wide, flat bottomed, centre of gravity concentrated inboard and low. The most stable cross section without weighted keel is a half circle. It will always find itself floating flat side down. However, it is not a Weeble. Because of its width and shape, there is a lot of buoyant force outboard, like a catamaran, so it will tilt with the wave but it won't roll back and forth like a pendulum until it runs out of energy.
What you want to know is, what is the shape of the bottom and what is the ratio of center of gravity height to width. Size is not as important.

- Will (Dragonfly)

 

[Don S/V ILLusion]

My opinion is that going from a 22 to a 25 is a difference without a distinction.

 

[Stu Jackson]

I did that in 1987. You're much higher off the water, just seems to be more rocking. It really isn't.

 

[markwbird]

Probably not your imagination. Higher CG and wing keel would do that.

 

[Jackdaw]

Rolling is a function of cross sectional shape - width, dead rise, roundness of chine, height of center of gravity and, in light weight boats, rigging height and weight, giving a longer swinging moment up high.
Boats built like logs with a keel will roll a lot (think trawlers with heavy high cabins and masts). If they are narrow and fitted with large keels that present a broad profile to resist that roll and lots of weight down low, little or no rolling even on the side of a wave. They are like Weebles. Then there are boats who's hull cross section has inherent stability, wide, flat bottomed, centre of gravity concentrated inboard and low. The most stable cross section without weighted keel is a half circle. It will always find itself floating flat side down. However, it is not a Weeble. Because of its width and shape, there is a lot of buoyant force outboard, like a catamaran, so it will tilt with the wave but it won't roll back and forth like a pendulum until it runs out of energy.
What you want to know is, what is the shape of the bottom and what is the ratio of center of gravity height to width. Size is not as important.

- Will (Dragonfly)

That's the longest non-answer I've ever seen! Will you gotta get on the water.

I've owned both and the 25 was for same conditions more stable. The wider beam and greater freeboard will make any like angular motion bigger due to straight geometry.

 

[Will Gilmore]

That's the longest non-answer... you got to get on the water.

Gawd, you're right.

- Will (Dragonfly)

 

[LeslieTroyer]

Gawd, you're right.

- Will (Dragonfly)

Come on out I’ve got 19 mostly solo days planed (6-30 to 7-18). Always more fun with 2.

 

[Will Gilmore]

Come on out I’ve got 19 mostly solo days planed (6-30 to 7-18). Always more fun with 2.

Les, I promise, some day I will, but, as JD knows, I am swamped with starting a homestead business right now. I am trying to finish up a deck and then grout 500 s.f. of slate tile, build a new stoop, paint 2 bathrooms and install wainscotting, basically get our new rental house ready for our first AirBnB booking and I spent today digging out weeds from my wife's garden terrace and filling it back in with a truck load of mulch. There's more on that list, much more, like build the farmer's market booth, get all the necessary licensing and make more inventory for our first farmer's market/ craft fair endeavor next week. Blah blah...
SBO is my escape.
If you have ever worked construction, you'll know what I'm talking about. You're roofing with a small crew or framing or siding, whatever, and one of the guys stops, he holsters his hammer or puts his roofing gun down and straightens up. He sighs and reaches in his pocket and taps out a cigarette while palming his lighter. He lights up, takes a drag and admires the view from the rooftop for a couple of minutes. Then, he's back to work. Nobody objects or raises an eyebrow. It's the darnedest thing. If you stopped like that to unwrap a lollipop or pour yourself a cup of coffee out of your thermos, the forman would be all over you. Cigarettes, at least they use to be, are understood and tolerated.
Anyhow, I work mostly alone and that is how it is with me, my smart phone and SBO. I'm addicted and I need regular fixes. Only water and sail will detox me. That or make it worse.

Les, JS, Kermit, TomY, Shadow, rgranger, CrazyDave, DrJudyB, dlochner, JamesG, SFS, and many others, even JD and KG, I know we have our different perspectives, but I consider you my neosenipals. Life is a little sweeter with you all in it.
Sorry, don't mean to hijack another thread.

So, back to the real or imagined rolling of a larger boat. It is a worthy point about being higher off the water. Not sure? Sit at the spreaders and feel the roll. Same rate as on the deck, much larger swing.

- Will (Dragonfly)

 

[MaryEllaRose]

Rolling is a function of cross sectional shape - width, dead rise, roundness of chine, height of center of gravity and, in light weight boats, rigging height and weight, giving a longer swinging moment up high.
Boats built like logs with a keel will roll a lot (think trawlers with heavy high cabins and masts). If they are narrow and fitted with large keels that present a broad profile to resist that roll and lots of weight down low, little or no rolling even on the side of a wave. They are like Weebles. Then there are boats who's hull cross section has inherent stability, wide, flat bottomed, centre of gravity concentrated inboard and low. The most stable cross section without weighted keel is a half circle. It will always find itself floating flat side down. However, it is not a Weeble. Because of its width and shape, there is a lot of buoyant force outboard, like a catamaran, so it will tilt with the wave but it won't roll back and forth like a pendulum until it runs out of energy.
What you want to know is, what is the shape of the bottom and what is the ratio of center of gravity height to width. Size is not as important.

Thanx for the help but most of that went right over my head. It makes sense, though. A higher center of gravity and the smaller area that the wing keel presents would account for more roll. Maybe I was expecting the rock of Gibraltar but it is what it is. At nearly twice the weight it is definitely a more stable platform.

Tom G
- Will (Dragonfly)

 

[Apex]

will, u have a lot of irons in the fire. hope your respobses are at least voice to text. i hat typing on a tiny keyboard.

...now back to work. errr correction out to the water.

as far as 25 goes it does move, but with sails pulling hard she can handle quite a bit.

 

[mm2347]

A good bunch of guys! A well-versed teck. type that seeks efficiency and an artsie talented craftsman that will add to beautify yet both seem to understand the other and show respect! Hopefully, it's contagious.

 

[Alansails]

We had our Catalina 25 (Tall rig/Swing keel) on Lake Erie and because Erie is a shallow lake and in the western basin there is ALOT of shallow boat chop waves. we would be aware of the chop/pitching, but again it did not seem too bad. We bought our 310 with a different bottom design and wing keel and obviously twice the weight, we do not feel that as bad any more but we still do see some of that pitch!

 

[jssailem]

Bigger boat. Greater mass. Needs bigger waves more energy to move it