Roller / Reef Furling Genoa basics

[JJ]

Clarification on area vs overlap: Correctly stated the "percent overlap" of a 100 percent jib is 50% less than a 150% genoa. However in terms of square footage there is a much grater difference because as you furl the sail in the luff length reduces as well as the foot & L/P. To calculate the square footage you would multiply the luff times the L/P and divide by 2.

Percent overlap is not calculated on foot length as was stated somewhere above. Gordmay had it correct. The reason for that is as follows; foot length is related to clew height but L/P is not. A headsail with a very high clew will have a long foot which is mosty going up, not aft. An L/P dimension is a true measure of how far aft the sail will go.

Another point not covered is this; When roller reefing a sail to a smaller size , shape enhancers like foam luff pads are irrelevant to upwind performance unless you take the time to re-lead the jib sheet to an inboard track (which very few people do in a furling application). Most people just leave it sheeted to the rail.

Finally with regard to modifying an existing hank on genoa for furling. This is not recommended in most cases. Since your old genoa will likely be too long on the luff after the furler is installed it will need to be recut. Then a luff tape must be added and finally a UV cover. These modifications can become costly and when you are done you still have a sail built from a cloth that is lighter than it should be for reefing. Hank on genoas are built for light air applications so the cloth weight is lighter. Furling genoas are built heavier to take the loads while reefed (just as a working jib is built heavier than a genoa). If you have to do it for economy reasons he best conversion would be from a working jib or a number #2 genoa since they are heavier by design. To further economize, if the sail you want to convert is a few years old then skip adding the UV cover because the sun will probable finish it off about the same ytime as it wears out anyway.

hope that helps.

jim

JJ has made a good point about relocating jib sheets. With a roller reefing system this can be problematic. My approach on my mono was to use Garhauer adjustable genoa cars, but this does not give me nearly as good an angle when reefed to a working sail as a secondary, inboard location for the sheet blocks. I found an idea, sorry I have not been able to remember where, but it allows for not only adjustment of the attack angle of the sheet, but also will bring it inboard. Coupled with a genoa car system, you can effectively trim sails from 150% to 50% and keep the sheet angle adjusted. Add a port and starboard padeye inboard, on the coach roof in my case. A line is rigged to a block on the padeyes, and another block that rides the jib sheet. the other end goes back to a rope clutch in the cockpit. There will be some chafing on this line, but, again, compromise. This will allow the jibsheet to be pulled down forward of the genoa car, and to be pulled inboard when pointing with the jib reefed down to 100% or less. This is the design I am installing on my trimaran. I have not tested it, but the theory is sound.

[capt lar]

Tangent - What about the pros and cons of sweeper vs. high cut ? I was talking with a salty owner the other day who said he had changed over to high cut because he was sick of not being able to easily see around the jib. He felt his boat lost no significant drive ? Comments ? Opinions ?

Larry

I depends on the boat. Visibility aside, our ketch sails much better with the high cut jib The decksweeper was the same overlap, but in similar conditions, we would lose about a knot in performance. It also caused substantially more helm. Moving the center of effort higher with the high cut genoa seemed to balance the boat better in all conditions.

[James Ross]

Cost is not an issue if you build your own .Niether is jamming. Mine cost $80 for materials and two days work,and being a 5/8th ID aluminium pipe on a 5/16th headstay, there is not much chance of anything jamming. It is similar to the Simplicity rig.I sailed twice thru the tradewind belt, 4,000 milesX2, to windward with no problem. Lots of squalls and lots of reefing. No problem. With a low cut genoa I had to put a line from a chainplate , over the sheet and back to get the right angle. When I reefed I just pulled this line in until the angle was right, and let it out when unreefing. I put a much bigger drum( 14inches overall with 7 inches inside on the drum) which made reefing much easier and gave me a much greater mechainical advantage. Go as big as you can on the drum.If it doesnt set perfectly , just sail a little freer which is a good idea in stronger winds anyway.I remember seeing the entire horizong polka dotted with squalls. I wouldn't be so foolish as to want to change headsails singlehanded ,every few minutes for 57 days , just to be a bit more efficient and trendy.

I agree about the cost issue, but building one can get harry for allot of us. A few years ago I saw a unit at a boat show that was simple and inexpensive. Every other unit I had used, jammed. After about three years, I bought one of these units. I spent time getting to know the the people who were selling the unit. I was so impressed with them, and with the product that I not only bought a system for my boat but offered to sell the furlers locally. To date, it is the best system I have used, and the cost is less than half of the nearest competiter. I have mentioned it before. It is called Reefurl. Here is a photos of the unit I have. My wife loves it. She can furl in the 135 without using a winch, and it has never jammed on us. I am not actively selling tham right now because I have too many things on my plate, but they have a website www.furlings.com
Here is a photo:
The down side is more windage, and it is bulky. I believe the weight aloft is not enough to be a concern. And, if you still want to use a hank on sail, you are out of luck inless you add an additional forestay.
It is installed with basic hand tools, and took me about 2 hours. It has no moving parts. (well, maybe one, it has it's own halyard, so it does have a sheave at the top for the halyard)

[Brewman]

Real novice here, sailing a 33 Morgan Oi 76. Need lessons but that's coming up.
Question? In a wide river/ St. Johns/ Jax. Fl., 15 + kt wind off of my port stern, don't now the proper term for this, maybe a little surface current running with the boat, just the jib, the whole jib deployed, 234 sq. ft is all I know, roller furler set up, full of wind, little tell tales flying where I think they should, trying to stay in river channel, Boat won't turn to port. Totally pulling to starboard and me with it out of the channel.
Had to start 50 hp perkins, give it the gas and reef jib a good ways to get back to normal steering.
Tips? Analysis?
Thanks,
Brewman
Was sober I swear.W.

[roverhi]

Without the main in those conditions, the wind in the genoa is blowing the bow off with more force than the rudder can overpower. You'd need to let the sheet loose and luff the headsail to bring the bow up. You should start using the main or get up a bunch of speed and hope you can bring the bow through when you go hard a lee with the rudder. With most of the boats I've owned, put up the main before raising or unfurling the jib. Have better heading control with just the main as boat will tend to head up rather than fall off as wind increases. If the main is overpowered, the main sail behaves better if you slack the sail till it luffs badly to ease pressure on the rudder. Do have to be careful if DDW as sheeting in the main hard is the only way to depower.

Proper term for the point of sail in your description is a broad reach. Hard on the wind/beating, close reach, beam reach, broad reach, running DDW are points of sail from close to the wind to dead downwind.

[Brewman]

Thanks Roverhi,
Will experiment with all.
Single handing the boat and controlling the jib from the cockpit is a nice feature. Like all things, practice is key.
Before coming hard a lee with rudder, get up as much speed as poss., luff jib and then turn.
Main sail deployed on this 33 Morgan helps all.
Will check hydraulics on steering as well.
Brewman out.

[HappyMdRSailor]

Originally Posted by Brewman

Thanks Roverhi,
Will experiment with all.
Single handing the boat and controlling the jib from the cockpit is a nice feature. Like all things, practice is key.
Before coming hard a lee with rudder, get up as much speed as poss., luff jib and then turn.
Main sail deployed on this 33 Morgan helps all.
Will check hydraulics on steering as well.
Brewman out.

These girls need a clean bottom to help with turning... Current was also likely stronger than you thought, and with you... Hyd steering should be solid at each lock, watch the ram thru the port laz while you spin the wheel... lemme know if you need help with the bleed/pressurizing details...