Fractional Rig

[junohera]

I am thinking of buying a 28 foot long keeled cruiser (twister 28) for coastal cruising. The one I have in mind has a fractional rig

I was hoping someone could explain in simple terms the advantages and disadvantges of a fractional rig

Being new to the forum I hope I am not asking a question that has already been posted - if so sorry and just point me to the answer

thanks

[delmarrey]

The subject has come up several times but don't feel embarassed. There are a lot of posts here to try to sift through.
Jeff H has a fractional rig vessel and highly recommends them for ease in handling and weather. He's certainly convinced me! If he drops in I'm sure he'll be happy to explain more. Here is one of his posts to start with. And if you just click on his name in the main menu it will direct you to all of his posts which will have more info on fractional rigs. Here's a start..............

http://cruisersforum.com/showthread.php?s=&threadid=300

Happy surfing........................._/)

[BC Mike]

If you simply study a mast head rig and imagion what is happening when you tighten the wyres that hold it up. You can practice this with a plastic stir stick next time you have coffee. The mast is trying to buckle the tighter the rig is set, so lower shrouds are added to control the buckle. When you tighten the back stay adjuster to put tension on the forestay it just makes matters worse. With a fractional rig the forces trying to buckle are not as great and when you pull on the backstay the mast curves in a uniform kind of manner and helps flatten the main sail. The fore stay tension can not be as tight but you use the main sail and sheet to help keep it tight. Other advantages are a usually larger main and smaller headsails. I have a mast head so I am not trying to promote what I have. These are the basics there are other issues as well. Michael Casling

[junohera]

Thanks for your comments, this has put my mind at rest with regard to purchasing a boat with a fractional rig.

[Jeff H]

I apologize that this was written for another venue but it might still prove useful. Of the two rigs, masthead rigs are far and away the more common of the two rigs. It came about as a rule beating method for racing sailboats. Under the CCA and IOR racing rating rules, jib size was under penalized. This promoted small mainsails and big jibs.

On a fractional rig, the forestay hits the mast somewhere below the masthead (or a fraction of the overall height of the mast. It is not unusual to see fractional rigs referred to as a 2/3 (Folkboats), 3/4 (J-24) or 7/8th’s (Triton) rig.

Each rig has it advantages and disadvantages. There are some big advantages to a fractional rig for cruising and racing. For cruising you are dealing with smaller and easier to handle headsails Not only are the headsails smaller because of the shorter headsails but, because the headsails represent a smaller percentage of the overall sail area, you don’t need to have overlapping jibs. The sail area is made up in the mainsail.

The best fractional rigs often have purposely designed flexible masts and, when combined with a backstay adjuster permits quick, on the fly, depowering of both sails. Mainsails are easier than jibs to reef in a manner that results in an efficiently shaped sail for heavier conditions. It means that you don’t have to take the expense, complication, maintenance and performance hit of a mainsail furler. Controlling mast bend you can often avoid reefing as the winds build. Roller furling genoas have notoriously poor shape when partially furled. The smaller jibs of a fractional rig rarely need reefing and when they do the fact that they are often smaller or eveb non-overlapping results in a better partially furled shape.

Masthead rigs have larger running sails and so can typically point closer to dead down wind. They are a little more forgiving for a new sailor. Because Fractional rigs permit such a large range of easy adjustment they can be trimmed through a range of adjustments that results in a bigger range of speed both slower or faster than a masthead rig of similar sail area. The limited adjustment of a masthead rig means that you more or less live with what you have. Therefore a masthead rig neither has the opportunity for going really faster and with less heel, or going much slower either.

My biggest problem with Masthead rigs is that you really need to carry more headsails and make more headsail changes. This is partially a function of the responsibility of the jib for drive. If you take a Fractional Rig 100% jib on a 28-footer it might be 150 s.f. and its 150% Genoa would be 225 square feet. But on a masthead rig 28 footer the 100% jib might be as much as 225 to 250 square feet and its 150% Genoa would be 337 S.F. to 375 s.f. That is a really big sail to manhandle and when you increase the size of a sail by 125 S.F. vs. only 75 s.f. there is a much smaller wind range that the bigger sail can be carried in so you might end up also carrying a number 2 Genoa as well as a working jib and a 150% #1 Genoa. With roller furling you end up sailing more frequently with (much less efficient) partially rolled up sails.

I strongly favor Fractional rigs for coastal sailing because the are so much easier to tack and jibe, you are not carrying around the big winches and as many large sails, and subjecting the boat to the much higher loads of a masthead rig. The lower rig loads can also mean a longer standing rigging lifespan and lower stresses on the boat. Fractional rigs generally lack the redundancy of masthead rigs in that a properly designed fractional rig only has a single set of lower shrouds.

Jeff

[Steve Rust]

I recently read a story of a guy who sailed his Twister from New Zealand to Chile and back with no serious problems. Nice looking boat too. Good luck.

[IrieSailor]

Been having an excellant conversation with "Weyalan" On a post: "forestay & backstay tension" on fractional rigs. Have recently aquired a 33 ft racer with a fractional rig and have been slowly learning the in's & out's of setting up thease rigs, useing running backs ect. Might be helpfull to ckeck out the thread.. Covers some of the the Pro's and Con's as well.

[barnakiel]

A fractional may and often will have a better mainsail / jib ratio. Such boats may have better drive downwind. Many top rigged boats are rigged like this to get the max advantage of some racing formulas of very little use for a cruiser.

If I had more choice I would go for a fractional rig for cruising - provided the main is big enough todrive the boat comfortably on its own.

b.