IOR Extensions- Flat Counter?

Discussion in 'Boat Design' started by Velsia, Nov 18, 2010.

  1. Velsia
    Joined: Oct 2008
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    Location: Jersey C.I

    Velsia Floater

    I recently recieved some old plans for a mini tonner built in 1979. There were speculative additions made to the lines plan with the counter extended to make it fit into the quarter ton rule. The way it has been drawn the is with the rocker for the extension not following that of the hull and being absolutely horizontal giving it an un-natural and ugly form. This is not the first time I have seen this and have seen it on a few quarter tonners on the water.

    Can any of the more learned here explain this terrible profile. If the extension followed the hull line would this cause to big a stern wake creating suction? Surely the abrubt change in directions causes all sorts of problems to waterflow and balance. Someone please help
     
  2. Crag Cay
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    Crag Cay Senior Member

    A picture of the intended extension would help!

    But in general, you needed to do more than simply lengthen a mini tonner for it to rate as a quarter tonner. There were complex aft measurement points which would have to 'work together' to make the rule believe it was looking at a bigger boat. For such an extension to be successful, they must have believed that despite any weight or hydrodynamic penalty the boat would still be fast enough to sail to its new rating.
     
  3. gonzo
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    gonzo Senior Member

    1979 is at the time IOR was producing extremes that handles very badly. Unless you have an absolute love for that design, burn it.
     
  4. Paul B

    Paul B Previous Member

    Nonsense.

    By 1979 Mini Tonners and Quarter Tonners were past the heavyweight pintail era of the IOR rule. Some very cool boats like Bullitt and Mr. Bill's Dog were top performers then.

    Even the bigger IOR boats of that time were quite moderate. The Jeremy Rodgers Contessa 39 won the Admiral's Cup that year, including being the top scoring AC boat in the Fastnet Race.

    Runner up overall in the '79 AC was the Dubois designed Police Car, which was lighter, fractionally rigged, and a surfing machine downwind in a breeze.

    The well-designed IOR boats of 1979 were fun to sail.
     
  5. Paul B

    Paul B Previous Member

    If the extension followed the canoe body shape and rocker then the extension would end up way up in the air above the water.

    The reason for the extension would be to increase the waterline. Therefore the counter has to be the way you see it on the drawing. Once the boat heels over the water will see a shape with less distortion.

    Regardless, I don't think the changes would have made it a competitive QT.
     
  6. gonzo
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    gonzo Senior Member

    You are looking at a design made to beat a rule. It has nothing to do with good handling or real speed. The rule is fairly complicated.
     
  7. Paul B

    Paul B Previous Member

    IOR boats were not slow during their era, especailly upwind. Sure, you could make something faster by making it lighter, more powerful, and wider in the stern, but the IOR boats were already faster than more than 90% of the boats of their time.

    Saying IOR boats had no real speed is like saying Indy Cars have no real speed because they are designed to a rule and could be made faster.


    As far as handling goes, a 1979 IOR boat had better handling than most boats available at the time. All the "handling issues" would go away if you simply sailed a few degrees higher when overpowered downwind, or just put up less sail. Neither of those options were good for winning races.

    All the "IOR boats are ill handling" stories come from sailing with too much sail up and trying to press down too much while overpowered. Things like BCCs or Alberg 30s were even worse when they were sailed the same way in the same conditions.

    Saying someone should destroy their 1979 Mini Tonner because it is ill handling is a pretty ignorant point of view.
     
  8. jehardiman
    Joined: Aug 2004
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    jehardiman Senior Member

    Wether they sailed well or poorly, a lot of IOR boats had to be modified after the '78 "Saturday Night Massacre"; a smokey room change in the IOR rule that resulted some of the smaller boats gaining a foot or more in rating overnight. This change was brought about by the smaller boats dominating events; not, as many think, to precieved problems from the Fastnet (which came after the major after girth station change, though it generated many changes also); The bad thing was, some of the designers had inside info what changes were comming and some didn't. This lead to a lot of really weird looking aft girth point modifications hastely done.

    Anyway Velsia, the weird lines aft on most 1/4Tonners was a manipulation of the aft girth station to get the maximum sailing waterline at the maximum rated length in class.

    Edit to add. It is also important to remember that the boats were measured floating upright with "normal stores"...which opened the door to the whole "Louisiana Crude" measurement scandal, and the near death of SORC.
     
  9. Paul B

    Paul B Previous Member

    We're getting a bit off topic here.

    The rule change of 1978 wasn't done in any "smokey room" or any back room either. In Nov. 1977 the ORC directed the ITC to change the rule to deal with the issues of light displacement and other attributes that were producing yachts that were prone to capsizing, breaking up, and sinking. The lightweight daggerboard boats that were dominating the fleets up to the One Ton size were not what most of the owners wanted to go to sea in.

    It wasn't so much the size of the boat that was penalized, it was the type. Some One Tonners were hit more than any QTs, over 2 feet of rating in at least one case.

    The ITC included Olin Stephens and Gary Mull. They received input from about 10 of the top designers of the day. There was a hand drawn graph comparing SA/DSPL vs DSPL/L with all the top boats from past years represented. The ITC tried to make changes that would be inclusive of the boats that best fit the graph and the outliers were penalized. I have held that graph in my hand and in fact placed it in an envelope to send to the RORC years later, for framing and hanging on the wall at the clubhouse.


    This was done on all IOR boats, not only QTs. It was just done there first since the cost of experimentation was less than trying something new at the Two Ton size. The loophole for the long overhang of the transom past the AGS was not fixed in the '78 rule change, it was finally plugged after 1980. Even that did not change the way some designers changed the angle of the counter to better fit their idea of Fast.


    Crude's issue was having their certificate pulled for a supposed hull bump that did not meet the minimum radius criteria. The boat had been measured and received a certificate. However, after the SORC was concluded the certificate was pulled until a re-measurement could be made. The boat was sold during the SORC to Sweden for their AC trials, so the measurement had to wait until the boat was available in Sweden. Upon re-measurement there the boat rated within 0.1 feet of what she rated during the circuit. She should have been re-instated since the allowable delta was 0.2 feet.

    However, Tommy Dreyfus was not a favorite of the boys at the USYRU. The fact that he began legal proceedings against the USYRU did not help his cause. The USYRU did not follow their written procedure by pulling the certificate instead of re-rating assuming the bump did not comply (as was called for). So Dreyfus sued because he was in the business of selling sisterships and the incorrect ruling was potentially costing him money. Once that was started there was no way he was ever going to be re-instated, regardless of the result of the re-rating.


    In the same SORC there was a problem with the Williwaw certificate. They were tossed for supposedly having their BMW "Harvey" fill the bilge with water before measurement. This was later proven to be a crock of something, since the measurer would have seen the 40 cubic feet of water that would have been required to sink the boat the amount the measurer claimed the floatation was off by. These boats had no bilge. Regardless, Seymore was dis-invited by USYRU from playing for the next two years.
     
  10. Velsia
    Joined: Oct 2008
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    Velsia Floater

    Hey thanks guys for all your input. Maybe I should redefine my problem a bit more clearly. The Mini Tonner in question I own. I have sailed her over a thousand miles though mostly cruising because of my circumstances. I find her very balanced and she excels in heavy weather. Only this summer I managed to get my fastest speed on her of 12.4kt on a wave off Le Roche Douvre, Brittany. During her IOR heyday she reached some distinction winning in her class twice the Cowes-Dinard race and once the Cork-Jersey.
    Now my circumstances have changed. I sail professionally away from home thus can use her less. Because of this I have taken her out of the water and will devote my time with her to modifications and refit.
    Their is locally a large quarter ton class and I think at the time of her build. The builder contacted the designer and asked if modifications could be made to the design to make her 1/4 ton. This prospective change was put on paper as a scoop. (Sorry Crag Cay, the plans are going in to the scanners today for conversion to PDF, will post picture later). There is only one mini tonner in the class but over ten quarters. Thus my contemplation of change.
    I think Gonzo you are being a bit Rash in saying to burn these plans, at the least they are well constructed and informative. In these days of cad it is good to see pencil lines.
    Particulars
    Ed Dubois Mini Ton Racing Sloop "Mischief 24"
    LOA: 23.4 ft
    LWL: 19.15
    BEAM OVERALL: 8.195
    Draft: 4.56ft
    DISP loaded: 2162.6lb
     
  11. jehardiman
    Joined: Aug 2004
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    jehardiman Senior Member

    I think wether it was a smokey room or not depends on which side of the door you were standing. Because of the rate at which design generations were advancing, knowledge of the proposed rule changes made or broke several designers careers in the NorCal sailing scene. Several designers who where privy to the changes beforehand designed and built boats before the rule change was made that would have never rated in, but they cleaned up after 3/4th of the other boats in class had to be modified. But you are correct that it was aimed all small boats. I had Gary Mull quoted to me as saying about the change: "People who spend a lot of money on a big boat don't want to lose to a smaller one".

    Anyway, back to the topic. Yes, I know of several boats that have had patches added aft playing with the measurement points to get the same basic hull to rate to a given class. I sailed on a Santana "39" where we used to talk about putting zippers on the non-structural transom extension to change her rating.
     
  12. Paul B

    Paul B Previous Member

    I woud like to hear more about what designers had "inside info" and what boats were designed and built before others knew about the rule changes. How would they have not "rated in" before the rule change?

    What boats were built and had to be modified because the designer was left out of the loop on this rule change?

    I would also like to know what NorCal designer(s) had their design career(s) made/broken due to being left out of this knowledge.
     

  13. Paul B

    Paul B Previous Member

    I would not expect to modify a Mini Tonner and compete with well prepared and sailed Quarter Tonners. Even with the hull extension and probably a larger sailplan ($$) you will not be as quick.

    There is a growing Mini Ton fleet in the UK (http://www.minitonner.com/). Perhaps you could get a good price for the old Mini and move up to a real QT? I know some good boats come available from time to time at the QT Class site (http://www.quartertonclass.org/).
     
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