I know articles have been written about it ,but according to some articles a fractional rig is superior to the top mast rig(mast head). If this is the case, why some top leading manufacturers are outfitting their boats with mast top rigs. example: a production racing boat/cruiser C&C 99? What do you failors think about it from a practical stand point - I have to get a new mast form my 1991 Hunter 30 which had originally a fractional rig and a pretty poor sail area to displacement ratio of 15.5 making it quite slow. So if I install a mast top rig, increasing the potential sail area, would this make the whole boat faster? Any opinioms will be greeatly appreciated!!!
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why
Most traditional racing handicap formulas have been based upon 100% of sail area, which means that a masthead boat using a 150% genoa is able to use sail area for which it is not penalized. Take the handicapping formulas away, and there's absolutely no reason to go masthead. Look at almost every box rule, including the America's Cup Rule, and you'll find designers opting to go with fraction rigs. So if you want to increase your SA/D ratio, take a hint from the IACC boats and add more roach to the main via full battens.
Most traditional racing handicap formulas have been based upon 100% of sail area, which means that a masthead boat using a 150% genoa is able to use sail area for which it is not penalized. Take the handicapping formulas away, and there's absolutely no reason to go masthead. Look at almost every box rule, including the America's Cup Rule, and you'll find designers opting to go with fraction rigs. So if you want to increase your SA/D ratio, take a hint from the IACC boats and add more roach to the main via full battens.
OK, just a minute.
He said he wants to increase sail area to make a slow boat less-so. It doesn't sound like a racing handicap is first on the list. Even if so, it's hard to make the connection of the IACC rule, to a Hunter 30. But Andre, don't even THINK about changing your rig without working with a Naval Architect.
He said he wants to increase sail area to make a slow boat less-so. It doesn't sound like a racing handicap is first on the list. Even if so, it's hard to make the connection of the IACC rule, to a Hunter 30. But Andre, don't even THINK about changing your rig without working with a Naval Architect.
Changing a rig
OK, Fre I heard your answer. I very much valu your opinion and I consider you an expert(especially after checking you massive project with your Hunter), but do I really need a naval architect to fit the same length mast in the same spot as oryginal, with the nly difference being that the forestay will be attached to the top of the mast vs. a few inches lower?
OK, Fre I heard your answer. I very much valu your opinion and I consider you an expert(especially after checking you massive project with your Hunter), but do I really need a naval architect to fit the same length mast in the same spot as oryginal, with the nly difference being that the forestay will be attached to the top of the mast vs. a few inches lower?
With all factors equal, probably not.
I assume you have a B&R rig. That has to be kept in mind. The spreader tip alignment has to be right with these single point connection rigs. And no matter what rig you have or want to change to, there is no substitution for proper alignment. But the above is only addressing rig retention. Once you decide to use it, other factors come into play. Foremost is center of effort. If your CE is drastically changed, the boat will at least be slower, if not dangerous. Unless you have a source for cheap parts and labor, changing the design of your boats' rig is a dubious project. Not worth the cash. Like John said "Why?". Trade for another boat.
I assume you have a B&R rig. That has to be kept in mind. The spreader tip alignment has to be right with these single point connection rigs. And no matter what rig you have or want to change to, there is no substitution for proper alignment. But the above is only addressing rig retention. Once you decide to use it, other factors come into play. Foremost is center of effort. If your CE is drastically changed, the boat will at least be slower, if not dangerous. Unless you have a source for cheap parts and labor, changing the design of your boats' rig is a dubious project. Not worth the cash. Like John said "Why?". Trade for another boat.
Selden or other Mfg...
Since you have to replace your mast anyway, why not take advantage of the people that make the rigs? I know that Selden will work with you, and I'm guessing that anyone else that makes masts will also in hopes of a sale. They have the engineers on staff to do all the calculations. If you are looking to change the mast anyway, why stop at only the fractional/full question. How about more height, and a longer boom? That will give sail area as well. If you don't care about the ratings, why not open yourself up to other answers for your results? Be aware, changes from the original may make the boat faster, but it could also lower its overall value because now it is a one-of-a-kind. Steve
Since you have to replace your mast anyway, why not take advantage of the people that make the rigs? I know that Selden will work with you, and I'm guessing that anyone else that makes masts will also in hopes of a sale. They have the engineers on staff to do all the calculations. If you are looking to change the mast anyway, why stop at only the fractional/full question. How about more height, and a longer boom? That will give sail area as well. If you don't care about the ratings, why not open yourself up to other answers for your results? Be aware, changes from the original may make the boat faster, but it could also lower its overall value because now it is a one-of-a-kind. Steve
mor on the new rig
Folks, points well taken. here is the difference. I can have similar to original,used mast for $3500. The new mast from C&C99 I can have for $1000 (long story why this price). So my question is - is it worth paying $2500 more for the aryginal fractional rig mast ? Waht do you guys think? Steve, no need for sarcazm, I am not extending the mast and the boom, all dimentions saty exactly the same. The only difference is the Mast top rig , not the fractional set up. Comments? Thank you
Folks, points well taken. here is the difference. I can have similar to original,used mast for $3500. The new mast from C&C99 I can have for $1000 (long story why this price). So my question is - is it worth paying $2500 more for the aryginal fractional rig mast ? Waht do you guys think? Steve, no need for sarcazm, I am not extending the mast and the boom, all dimentions saty exactly the same. The only difference is the Mast top rig , not the fractional set up. Comments? Thank you
Location of Mast
From what I have seen the Fractional rigs are more forwards than masthead rigs. My 1990 Hunter 27 has about one less foot on the J dimension than its Cherubini predecessor but adds a foot on the boom. In fact the J dimension is closer to the earlier 25' model. I think using a masthead jib will give you lee helm. My 90 model uses a Z-Spar rig available from US Spars. If your boat uses another rig than waht it was designed with, no one may ever want to race against you in any handicapped fleet. You would have an unfair advantage, and since its either handicap or one design, what's the point of a fast boat you can't enter in a race without a protest every time.
From what I have seen the Fractional rigs are more forwards than masthead rigs. My 1990 Hunter 27 has about one less foot on the J dimension than its Cherubini predecessor but adds a foot on the boom. In fact the J dimension is closer to the earlier 25' model. I think using a masthead jib will give you lee helm. My 90 model uses a Z-Spar rig available from US Spars. If your boat uses another rig than waht it was designed with, no one may ever want to race against you in any handicapped fleet. You would have an unfair advantage, and since its either handicap or one design, what's the point of a fast boat you can't enter in a race without a protest every time.
Design Sail Area
When your boat was designed it was designed with a sail area in mind. On boats with the same hull like a J 29 have different location's of the mast in the boat. A Frac J 29 has a mast that is more forward and has a bigger main sail then the Mast Head J 29. They also have differnt PHRF #'s. Looking at some of the pictures of the 91 Hunter 30 going from a Frac to a Masthead would be more then a few inches. I think you will throw the sail plan of the boat out of wack. The Frac Rig Hunter's are not B & R Rigs so this does not play into it. You will also have a one off boat and this could hurt resale of the boat. You could always try it and see how it works of talk to a yacht designer and get his input before making the change. But looking at the rig this is not the way I would go I would instead look at the main and get a Main Sail that has more roach for ther added sail area. Reason so many racing boats have the Frac rig is more for adjustment than anything. A Tripp 33 has a Frac rig with Runners for Head Stay tension. Plus a Backstay, this way they can have tension on the head stay with out tension on the back stay. This allow's the crew to squeze more speed out of the boat. On mast head rig you could not do this. Cliff
When your boat was designed it was designed with a sail area in mind. On boats with the same hull like a J 29 have different location's of the mast in the boat. A Frac J 29 has a mast that is more forward and has a bigger main sail then the Mast Head J 29. They also have differnt PHRF #'s. Looking at some of the pictures of the 91 Hunter 30 going from a Frac to a Masthead would be more then a few inches. I think you will throw the sail plan of the boat out of wack. The Frac Rig Hunter's are not B & R Rigs so this does not play into it. You will also have a one off boat and this could hurt resale of the boat. You could always try it and see how it works of talk to a yacht designer and get his input before making the change. But looking at the rig this is not the way I would go I would instead look at the main and get a Main Sail that has more roach for ther added sail area. Reason so many racing boats have the Frac rig is more for adjustment than anything. A Tripp 33 has a Frac rig with Runners for Head Stay tension. Plus a Backstay, this way they can have tension on the head stay with out tension on the back stay. This allow's the crew to squeze more speed out of the boat. On mast head rig you could not do this. Cliff
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