Blair,
Just my opinion. I have owned both furling mains and traditional mains. If you are concerned about performance, you should get a traditional main. You give up quite a bit of performance with a roller-furling main. Most of the newer Catalinas (the newer "5" series) were designed with a roller-furling main in mind, and have a larger rig to compensate. Older Catalinas (including the 36 and 380) were designed for a traditional main, and when you put a furling main on them, you lose a bunch of power. More convenience, but less performance. Yes, furling mains can get stuck in the mast if you don't furl them tightly, but that is due to operator error, not a design fault. Furling mains are easier to reef, and the reef points are "infinite", but the shape of a partially furled main is not as good as a reefed traditional main, just as the shape of a partially furled genoa isn't as good as a smaller, flatter jib. I have heard from sailors much more knowledgeable than I am that just about everything in sailboat design is a compromise. You have to decide where on the spectrum of design choices you want to be. Your boat, your choice.

True... I've no experience with furling mains, but I've heard they can also:

[LIST]
[*]Increase weight aloft
[*]Preclude full (horizontal) battened mains
[*]Allow more water to drain down into the bilge on a keel stepped mast
[*]And if they jam out in a blow you're knackered!
[/LIST]

FWIW

I have a 2004 Catalina 36 MkII wing keel & standard height furling mast. What you loose with roller furling is the roach which makes the sail less powerful. When I was researching, if I remember correctly, I found the theoretical hull speed of the tall rig traditional main to be 7.6kts and the standard rig roller main 7.4kts. Maybe an issue racing but probably not cruising.

I just replaced my sails with Quantum MC7500 (carbon fiber & techron). The shape is unbelievable and the boat moves effortlessly.

My previous cruising boat had a traditional mast and after using the roller furling mast, I will never go back. No more flaking or hoisting. Just out haul & in haul to infinitely reef when necessary. The Quantum MC7500 by design holds its shape pretty well no matter how much is pulled in. No jam furling is a piece of cake once you learn how much halyard tension, out haul tension, and boom angle is necessary to make it furl and unfurl effortlessly.

Whispering Eye
Catalina 36 Mk II #2201

Whispering eye,

No doubt furling mains sacrifice speed for the ability to depower or furl quickly, it should have no effect on theoretical hull speed as that is a hydrodynamic limitation based on displacment, hull shape and length.
The polar diagrams may reflect the speed difference between mast height and furling sails but they are not likely to change theoretical hull speed.

Theoreticly.

Blair, I agree with Whispering Eye's skipper. Once you have (and enjoy) an in-mast furling main you will never want to go back. While, I agree it is true that your mainsail shape may not seem to be optimum, it suits me just fine.

I have owned four other sailboats, with our previous boat being a Catalina 25. I recall very well the hassle of dousing the main.

Now, as far as you mainsail becoming jammed in the mast, it has never happened to me on my boat. Never! and yet I was cautioned by a number of
sailors ([I]who just happened to be non in-mast mainsail boat owners BTW[/I]) that I would regret my choice of purchasing a Catalina 36 with this option. I love it and it always performs well for me. It's a paradigm shift, the Admiral and I have noticed that most new boats at the boat shows are equipped with this wonderful option.

After watching the other boats in the fleet pack their mains up, while I furl mine away, unless I was racing, I would never go back to traditional main ( or hankered on headsails).

Sent from my iPad using Tapatalk

Just don't get the idea that you can sail with just the main alone. You will make very little headway on any thing besides a broad reach or a run. With being said I still like the in mast furling, and so does the princess.
Mark

We have dutchman furling and lowering the main is no big deal as long as it is set up properly. Two single line reefs make reefing pretty simple and we get nice sail shape with the full battens. I don't like the added weight aloft of inmast furling but if I was buying a new boat or ever had to replace a rig I would seriously consider it.

Our boat won't sail on main alone, period, it just goes in circles and acts as if it has no rudder, too much power too far aft! It will sail quite nicely though on the genny alone on any point of sail.

Welcome to the 36IA Association Forum Blair; you will find it to a wonderful source of information on your vessel! BTW, I like your signature, a future Catalina owner.

This post has me reminiscing over the Zip-Stop main I had on my last 36 (a 1986). I could set the main with almost no effort in about 10 seconds.....seriously. True, it was a battenless main, but the boat seemed to move well. I miss that thing.

Mike

[Our boat won't sail on main alone, period, it just goes in circles and acts as if it has no rudder, too much power too far aft! It will sail quite nicely though on the genny alone on any point of sail.[
Huh,thats odd,i sail drills on all pts of sail with main alone..no power but steerage yes..full batt main.

Maybe ours is weird, but shortly after we got the boat we went out one day and for whatever reason shut the engine off before we put the main up, wind was on the beam and fairly light. Once the sail started to draw the boat just turned upwind. My wife was at the helm and she said the rudder wasn't working, I checked and it was, but the boat would just go up into the wind and stall unless you put the helm over the other way and then it would come around and repeat again, we did half a dozen loops before the lights went on. I thought I was back at the helm of a Beneteau for a minute. Rolled out the genny and off we sailed as normal.

I guess the center of effort is fairly far aft with this boat? If you reef the genny first in strong winds it does the same thing, only a lot faster and a lot more violent. Found that out the hard way too.

FWIW, we sail with the full 135% Genoa alone many times for various reasons and boat handles very well. Helm is mostly neutral, but definitely not lee helm.

I have also sailed on just the main while we had our Genoa out for repair and while it was vastly underpowered, we could manage all points of sail. Not pointing very well, but sailing OK.

Right on Duane, we do the same but for me the reason is clear! It's SO easy to just roll out the Genoa and I [I]like [/I][U]easy[/U]. I guess that's why people go for the furling Main :)

Our Genoa is fairly new and has nice shape; the main is very old and tired, so deploying the main adds little to our performance much of the time, unless the wind is abeam or aft.

I plan to replace the main with a stack-pack like arrangement in the future to make using it faster and easier than taking off the cover with all the fasteners and the velcro for the dutchman lines. It sounds lazy, but things that are not relatively easy on a short-handed boat tend not to get done (or used).