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J24 Keel fairing - PHRF


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#1 JimB

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Posted 13 January 2004 - 05:10 PM

It is my understanding that the J24 OD allows the keel fairing to build up the leading edge of the keel to in effect move the keel forward a bit. I may not have this exactly right so please correct this preception if wrong.

I am told this fairing process is very expensive which would indicate to me that the modification is a definite performance improvement. Why else would the owner spend the big bucks, ( something like $5000 dollars)?

The reason I bring the question of a rating hit up when racing PHRF is as follows. We have 20 boat fleet of boats rating almost level at aprox 171 in our area. We now have 4 J24s in addition to a number of SR 21s, Santana 23s, S2 7.9s and Martin 242s. There was a J24 new to this mix last fall that had undergone the keel fairing/modification process by the previous owner. This J24 was fast and definitly pointed higher than the non faired J24s in the fleet. Now one of our existing J24 owners is talking about getting the keel job done. This J24 was our areas top boat before this new faired J24 came along, very well equipped and sailed. Now he wants the fairing job. He was very tough to beat before, now how much tougher is he going to be after the keel job?

I sail one of the Santana 23's. I am thinking about putting a new rudder design on my boat but am hesitant to do so because of a rating hit of at least 3 secs and I do not expect to get the same performance enhancement that the Js enjoy with their keel jobs. My thoughts are why should the J24s get away with no rating hit for their keel work if I am going to take a hit for a new rudder design.

My questions;

Has any PHRF club ever addressed the J24 keel fairing issue?

What does SA think about this issue?

#2 ChiGuy

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Posted 13 January 2004 - 05:27 PM

Just an opinion...

If a keel is faired to one-design specs, then it should not take a penalty under PHRF. I would report to the PHRF authority that the fairing had been done of course, and if possible, provide a new class measurement certificate.

I would think you could try to appeal either your rating, or the J/24 rating in your area.

#3 Bash24

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Posted 13 January 2004 - 05:51 PM

Agreed. PHRF assumes that your boat is in race ready condition. For a J24 that would mean making sure that all of the class "go fasts" are addressed. For me, that means that the PHRF rating is based upon a max foward minimum width keel. It is unfair to ask the guy to take a hit b/c his boat is prepped properly, it is also unfair for others to expect a brake because theirs isn't. You don't get a rating credit for old sails, you shouldn't get one for a keel in the wrong place.

The high level of class racing does mean that the J24 is a hard boat for the average guy to get to sail to its rating. The rating has been driven down by the pros that kicked ass with the boat back in the day, and the rating assumes your boat is perfect and other boat's ratings don't hold them to as high a standard. This is offset somewhat by the amount of sailing and tuning info out there on the boat that can help you get up to speed quickily.

I do think that you are over-estimating the effect of the keel job on the guy's performance. From experience, the speed difference between boats with a keel job and without is in the area of 1 to two boatlengths for every mile sailed. This is magnified somewhat in OD racing where if you lose 1/4 of a boatlength early, you are in the cheap seats. But for PHRF purposes, the difference is not that much, one bad tack and you are even. I'd tend to think if this guy is probably beating the others because of the total approach of his program, not just the keel job.

He can do whatever he wants within those extremely narrow class tolerances, and not take a hit.

#4 Still

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Posted 13 January 2004 - 05:52 PM

Well, I see BASH is lurking so certainly he'll have an opinion.

Yes, the "max forward" keel "mod" is deemed by most to be essential to have a competitive 1-D J/24. Some folks do the job themselves, and I'm not sure if your $5K guesstimate is correct. I believe the Waterline site has J/24 price lists; Custom Offshore might as well.

To your point: so long as the 24 stays class legal, I don't believe a ratings hit is called for.

Your best options are:

1) Do research to be sure the "spread" between your boat and the 24 is in line with national practice. Some places rate the J's at 168;

2) Be sure that your sails and bottom are optimized. Thats really what you are up against.

#5 charm

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Posted 13 January 2004 - 06:36 PM

Remember also that if that boat travels to any qualifying event, it will be measured and if it doesn't make measurment, it won't qualify for the nationals or whatever. I'm not certain which night you race, but on Tuesday nights the J24s don't race too seriously (the few that come out), they save it up for Thursdays when they're racing OD. Besides after a quick look at the results from last year, it looks like a well preped J24 that's been in Portland awhile lead the Tueday nights, and did very well on Thursdays too.

#6 jcc

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Posted 13 January 2004 - 06:44 PM

Any boat will benefit from a keel fairing job. If you can get templates for your keel and do not modify the keel from the designed shape, then you should not take a penalty hit.

On Lake Ontario, the J24 rates 165 and the J24 OD rates 162. The class legal spinnaker for the J 24 is oversize from the PHRF LO 183% max girth.

jcc

#7 Bash24

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Posted 13 January 2004 - 08:39 PM

Well, then you punish old boats. If you buy a new 10 then it has all the "the go fasts" built in. His rating is fixed, then the others boats get modifications to come up to the same level and they get a hit, not a good plan. Some J24s (all the new ones) come from the factory with the keel at max foward, some come with it a little futher back. You can't punish the old boats for doing mods that make them equal, it forces people to buy new boats. It is also ridiculous to have 2 measured J24s with different ratings.

#8 ChiGuy

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Posted 13 January 2004 - 09:06 PM

J Tuner...

Fairing a keel to class specs is fundamentally different than altering its shape to some different foil section.

#9 bownazi

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Posted 13 January 2004 - 09:23 PM

Tweaking the keel within the J/24 OD class rules should not be confused with adding 6 inches to the bottom (of the keel) and adding a 500 lb lead bulb to it. On most it's a matter of "moving" the keel 5-10mm. And as Bash said, if the new boats are popping out that way, why should I not be able to bring mine up to spec?

Agreed that the biggest advantage to a max forward min width keel is primarily psychological. It results in an exceedingly small performance increase. In J/24 OD, however, sometimes that is all you need to get off the start and j-u-s-t keep your nose in clear air.

This is a non-issue.

#10 Boudreaux

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Posted 13 January 2004 - 09:25 PM

I don't think the class rules say anything about the actual section do they? Just the max chord depth, max length and position. Within that envelope go frigging nuts!

I mean...this is no E22.

#11 Bash24

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Posted 13 January 2004 - 09:37 PM

I don't think the class rules say anything about the actual section do they? Just the max chord depth, max length and position. Within that envelope go frigging nuts!

I mean...this is no E22.

What are you smokin?

The J24 class rules are a hell of a lot more strict than the Etchells. Six sections of the keel have to be within tolerances and are measured at 10% incriments back from the leading edge. With the tolerances so tight, there is not much room to tweek the shape. Check the linkJ24 Keel Measurment

#12 rudimentary

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Posted 13 January 2004 - 09:57 PM

From a Perf perspective keel fairing can be one of the more lucrative "grey" areas that is expoited without penalty. Most regions allow "fairing" without penalty and yet few define what "fairing" is.

#13 JimB

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Posted 13 January 2004 - 10:09 PM

Tweaking the keel within the J/24 OD class rules should not be confused with adding 6 inches to the bottom (of the keel) and adding a 500 lb lead bulb to it. On most it's a matter of "moving" the keel 5-10mm. And as Bash said, if the new boats are popping out that way, why should I not be able to bring mine up to spec?

Agreed that the biggest advantage to a max forward min width keel is primarily psychological. It results in an exceedingly small performance increase. In J/24 OD, however, sometimes that is all you need to get off the start and j-u-s-t keep your nose in clear air.

This is a non-issue.

I am amazed that the J24 guys who opt for the keel forward fairing job will spend so much money and effort for such a small performance gain.

You are saying then that there would not be a 5 degree pointing advantage to be gained by doing the keel forward fairing?

#14 Still

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Posted 13 January 2004 - 10:21 PM

I am amazed that the J24 guys who opt for the keel forward fairing job will spend so much money and effort for such a small performance gain.

You are saying then that there would not be a 5 degree pointing advantage to be gained by doing the keel forward fairing?

Jim, if you go the an event like the J/24 East Coast Championships there will be 70 J/24's, hull numbers running fron 700 to about 5400, and you will almost never see a 5% pointing ability differential... and I'd guess that most, but not all of the boats have max forward keels.

The boats that aren't pointing typically have older sails or otherwise aren't dialed in, in terms of headstay length or spreader tension.

So yeah, guys do it to gain an improvement of <5%.

As mentioned above, if you can't hold your lane in a 30-50-90 boat fleet, soon you're headed for the cheap seats.

The investment you're talking about isn't that big a deal in dollar terms when you consider nice used 24's can be had for $12-18K. Fair the keel, get sails, you've got a competitive boat in a still feisty fleet for under $25K. Roughly comparable to a Melges, but lots cheaper than the Tartan 10 mentioned above.

So yes, its a rational choice. Most guys in the fleet will tell you its a no brainer.

#15 Bash24

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Posted 13 January 2004 - 10:22 PM

Nope not 5 degrees, maybe one or two degrees. The J24 guys spend so much because the want no excuses, they want to know the boat is perfect. If you take a stock boat from the '70s and do all the tricks, minimum mast, max J, Max forestay, proper spreader length and angle, keel max foward and mimimun and new sails, there might be 5 degrees there. But there is not 5 degrees in that keel job, the difference is mostly mental.

#16 Steve

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Posted 14 January 2004 - 01:38 AM

If you reported to your local PHRF rating commitee that you have moved your keel on your Santana 23 foreward by 10mm what do you think the reaction be,my guess is YOU would take a hit because the assumption would be that you did the mod from the way it came from the factory in the hope of a performance gain and that would be fair and im sure you would expect nothing less. WHY should it be different for the J24s? This is one of those situations where the PHRF boards need to grow a collective backbone and treat everyone the same, it doesnt matter if 2 J24s rate differently in the same PHRF fleet,they can still race even up in their one design races. Under PHRF you SHOULD fair your keel to templates if you can but you can NOT move it without a hit and if you are adding material to the front of the keel and removing material from the back,whos kidding who? thats not fairing.

#17 charm

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Posted 14 January 2004 - 06:17 AM

Jamba,

The altered J24s are almost always older boats that are adjusting their positions to apoint as far forward as allowed by class rules, in effect, they fitting it to the template. The new J24s come with the keel already forward. But since 99.99999% fo all J24s agree to sail level when they're sailing phrf, it is in their best interests in both phrf and OD to make the boat as fast as possible within class rules. Moving the keel forward is an accepted and expected alteration of a J24 in much the same way that having a mx length forestay and a min length mast is expected.

Somebody please help me understand this discussion. Is it really coming from folks that just don't understand a huge OD class like the J24? People buy J24s for the same reason people buy lasers, they're freakin everywhere. If you move there's a damn good chance that there will be a fleet where ever you go. So, my point is, OD boats that sometimes race in phrf fleets are not adjusting these things to improve their standings in the phrf fleet but rather in their respective OD fleets, they're altering their old boats so they act like the new ones.

Another example of a J24 alteration that would indirectly improve performance is the updating of the pre-1978(?) hatches to the modern ones. Kites come down quicker, it's easier for the crew to cross the boat etc. Do you non-J24 sailers think there should be phrf hit for that? The owners are improving the boat to match the new ones and the class rules. Do you think there should be a phrf hit for shortening the stanchions to class minimums? The old boat come with much taller stanchions that make hard hiking, well, hard; the new boats already have the shortened stanchions.

I know I'm ranting here and I apologize but there are so many phrf vs OD arguments and it's stuff like this that starts 'em. These alterations actually make j24 sailing more OD. The boats which have been produced over the last 20 years (?) 25 years(?) are all different. By making the alterations to fit the class rules, the phrf rating all of these OD boats are given will acutually be more acurate (despite the fact that the amazing sailors who have all raced these things have made them look faster then they really are)

#18 Steve

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Posted 14 January 2004 - 02:20 PM

[QUOTE]Charm, i dont think anyone would sugest that a J24 be penalised for altering hatches or shortening stanchions because in most fleets any other boat that did the same would not be hit,the whole issue as i see it is that everyone MUST be treated THE SAME, ie,if joe blow unbolts the keel on his Wavelength 24,and moves it fwd hes going to be penalised so why not a J24? remember PHRF assumes you make an alteration for a performance improvement.If the PHRF committees were to treat everyone in a consistent way they woulnt piss people off so much(see the EDs rant)There are a lot of grey areas when it comes to ratings,moving your keel isnt one of them.

#19 Bash24

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Posted 14 January 2004 - 02:35 PM

Steve, you are not looking at the bigger picture. If you produce boats for 25 years at different factories all over the world, there are going to be some differences. Under your system, people would just buy boats that already have the keel in the right place (the new ones) and say, "I didn't move anything, it came like that." The next guy then wants to be competitive, he can't shape his keel without a rating hit so he sells his boat and buys a new one if he can. This would kill low budget J24 guys and those are the ones that you see in PHRF fleets.

Take my 1979 J24 as an example: the keel is min width and max foward. It was like that when I bought it. I don't know if it was "moved" at some point or if it came from the mold like that, I just bought it and started racing. Now say I start beating some of the J24s in the local PHRF fleet and it turns out that their keel isn't like mine. The other guys then move their keel to the point where it matches mine. Well, here comes Steve and he is giving you a 3 second hit. Now we have identical J24s but some rate 3 seconds faster than others. What are we going to do about that?

Are you suggesting that the local PHRF boards get into the keel measuring business? Are they going to have to own templates for each boat in their fleet and measure the keels? Keep it simple, here is the OD rating for the J24____, if you follow the class rules, that is your rating.

#20 redboat

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Posted 14 January 2004 - 02:49 PM

I guess I'm directing this to Bash as it's a J24 question:

Now that TPI and Waterline are one and the same, if you buy a new J24, does it come with a full Waterline bottom/foil fairing job? Or do you have to order that extra?

Guess I could have contacted the folks in RI but this is a hell of a lot easier.

#21 Bash24

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Posted 14 January 2004 - 02:57 PM

Yeah, it comes ready to race. The bottom is fair and the keel is in the max foward/min thickness right from the factory.

Here is a link to a new boat that is for sale, check out that bottom.

New J24

#22 Still

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Posted 14 January 2004 - 04:26 PM

If joe blow unbolts the keel on his Wavelength 24,and moves it fwd hes going to be penalised so why not a J24?

Here's the point, stated slightly differently than Bash:

Your J/24 is a "melon" - instead of coming from the factory with the keel 10 mm behind station 5 (or whatever), it is 25mm behind station 5. Other J's come in right on the 10 mm button. Class rules says the keel can be at 10 mm. The boats are PHRF rated on the assumption that they are class legal (10 mm) J/24's.

By "modifying" the keel so that it is at the class legal 10 mm standard, its like rectifying the melon. Eliminating the production intolerance.

If the Wavelength guy moves the keel to where IT SHOULD HAVE been in the first place, then even he doesn't deserve a ratings hit. If he's doing some kind of Sean Langman/Grundig homebaked Frankenstein mod, then yeah, he's at his board's mercy.

And rightly so for thinking he's smarter than the guy who designed the boat in the first place.

#23 stumble

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Posted 14 January 2004 - 09:19 PM

Now so far everyone has been thinking about the shift forward, but what about a boat that comes out of the factory off center? A local j-24 was delivered used with a noticable abgle off center line in the keel. Basically it was put on crooked, and had the trailing edge shifted over about half an inch from center line. Should the owner be allowed to put it back into place, or would that also be a 'performance modification' and need a rating hit.

The reality is that boat builders accept tolerances that are pretty wide, and all faring does is bring the reality back inline with the theoretical numbers (which are the ones PHRF is supposed to measure). Certainly these modifications alter the boat for the better, but only to get it back to where it should have been in the first place.
And to argue that if it came out of the factory that way it can't be altered... well I have never sailed on a boat that wasn't altered in some way from factory specs... Should we also force a penalty for moving to carbon/graphite blocks instead of steel? Or hit someone for using low stretch lines, what about replacing winches with oversized ones... all of these things are routinely done. PHRF is supposes an onus on the owner to ensure that the boat is race ready and optimized. All of these modifications are just part of that, including the keel.

#24 bownazi

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Posted 14 January 2004 - 10:06 PM

for those who might be wondering (and since someone mentioned "unbolting")- "moving" the keel on a J/24 simply entails sanding off some of the trailing edge and building up the leading edge- and then making the whole thing fair/proper chord/foil demensions/class legal, etc.

That is what amazed me when I first started sailing in the J/24 class (east coasts, easters, midwinters) 5 years ago. It is SO DAMN COMPETITIVE. It boils down to taking fractions of a % of boatspeed (and doing EVERYTHING else perfect) to get an edge. It is a testament to taking a design, putting some class restrictions on it and then letting a group of people over many years of trial and error fumbling (and some technological edges in sailmaking) to figure out the absolute fastest configuration. It is brutal how competitive that group is. You walk up on that class and after one regatta it's like.... dayum... these mf's have got this %hit wired. You learn real quick how to like losing (and how to be humble) if you are a newbie. If you can't take that, you just pack up and don't come back. LOL



No BASH did not pay me to say that.

#25 Steve

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Posted 15 January 2004 - 01:28 AM

Bash, i may not be understanding the modification correctly,but what im gettting from you is that thru shoddy workmanship the keels were put on in different places,but i find this a bit hard to understand,please correct me if im wrong but dosnt the J24 have a molded sump as part of the hull? with the lead bolted to that,as a one design all the mold would have to come from a master plug so that sump would be in exactly the same location on all boats ever built,with a sump you would have to try hard to get the lead in the wrong location.Anyway i think i was making the point that fairing the keel to templates is a different thing to ,with filler,effectivly moving its location,i guess if i were in the market for a J24 i would decide what type of racing i was realistically going to do,if it was primarily going to be PHRF i would look for an unmodified one,much like im sure most guys who want to do mostly OD would seek out one with all the mod already done.

#26 Bash24

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Posted 15 January 2004 - 02:22 AM

Bash, i may not be understanding the modification correctly,but what im gettting from you is that thru shoddy workmanship the keels were put on in different places,but i find this a bit hard to understand,please correct me if im wrong but dosnt the J24 have a molded sump as part of the hull? with the lead bolted to that,as a one design all the mold would have to come from a master plug so that sump would be in exactly the same location on all boats ever built,with a sump you would have to try hard to get the lead in the wrong location.Anyway i think i was making the point that fairing the keel to templates is a different thing to ,with filler,effectivly moving its location,i guess if i were in the market for a J24 i would decide what type of racing i was realistically going to do,if it was primarily going to be PHRF i would look for an unmodified one,much like im sure most guys who want to do mostly OD would seek out one with all the mod already done.

Not quite that simple. Keep in mind we are talking 1 to 2 cm at the most. The sump only comes down a couple of inches from hull so there is the ability for there to be some play there. In addition, not all boats come out of the same mold come out the same way. Any spot fairing done at the factory could have an effect.

Finally, here is the real kicker. It is not like there is only one set of molds. These boats have been produced in, East Coast, West Coast, UK, Italy, Argentina, Australia, and Japan. Each factory had its own molds, and there is a lot of room for play there. And, no there is no "master plug" the other molds were made from an existing boat. The original boat was destroyed to make room at the factory for new ones. It is easy to see how there can be differences with multiple factories going for like 25yrs.

You also have to consider that a lot of these boats were produced before it what was known what keel position was fast. It was in the best interest of the factory to put the keel in the middle of the tolerance because it is less likely to be "off."

#27 knuckles

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Posted 15 January 2004 - 02:23 AM

If I was going to race a J/24 only under PHRF, I would make the forestay longer and put PHRF sized sails on it (biggest PHRF main and headsail allowed). I would stop dragging around the extra equipment that J/24 One Design rules require. I would not carry a motor (I don't know jack about the details of PHRF rules). I would carry a 1/2 oz. spinnaker.

But I only race J/24's in class events, so I don't need to worry about it.




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