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They have faired their keel with templates and know that:


Boats made prior to 1982 had keels that were particularily bad. Significant lead needs to be removed to get to minimum keel thickness. The accuracy of the keel improved on later boats, but for optimum performance the keel still needs to be faired to accurate templates. Some mid 80's boats had keels that were illegal because they were thinner than the Class Rule Minimums. Computer Keels' product design and instructions minimizes the skill and tools required to make accurate templates. The patented wrap around template design provides precise keel thickness and chordlength control, and very accurate alignment of the profile to the centerline of the boat. Keel fairing instructions explain the process and provide information to elimate or reduce keel blistering.


The Compukeel™ Template Kit consists of six section profiles precisely drawn in ink on Mylar for the locations defined in the class rules. The product design and instructions minimize the skill and tools required to make accurate templates using picture-mat board reinforced with wood strips (not included). This construction technique produces very accurate templates that are quickly and easily fabricated using a hand saw, utility stapler, ruler, and utility knife or, we can assemble the Compukeel™ Template Kit into ready to use Assembled Compukeel™ Templates for an additional charge.

Compukeel™ Template Kits and Assembled Templates are available for the J/24 keel and rudder with two different keel profiles. Most people use the proprietary design CKD (Computer Keels Design) which provides improved performance both up and down wind. The CKD model is fuller forward and carries the fullness more uniformily through out the profile, providing many of the benefits of moving the keel forward without the hassle. This profile is hydrodynamically fairer, establishes lift more rapidly, and is more stall resistant than the class rule profile. The establishment and maintenance of lift allows the helms person to more fully track changes in apparent wind, and makes the boat more responsive in choppy conditions. Reducing the tendency of the keel to stall makes the boat easier to sail upwind with the genoa in higher winds. The hydrodynamically fairer profile creates less drag which allows sailing closer to the mark on down wind runs with equal boat speed. Keel refairing on pre '82 boats with the CKD model is significantly quicker and easier because less lead and fiberglass must be removed. The other profile is the CRD model which incorporates the Class Rule Design minimum profiles.

Two versions of the Compukeel™ Template Kit and Assembled templates are available, the original, and the Compukeel™ II. The original Compukeel™ Templates and Template Kits for twenty-three years have been used to fair more keels than any other template product. The original comes with instructions to make templates using picture matboard reinforced with wood furring strips (not included). Also include are instructions explaining the keel fairing process and information on how to reduce or eliminate keel blistering.

The Compukeel™ II Templates and Template Kit have additional information on the patterns, a template locating ruler with tolerances, and expanded instructions that explain the keel fairing process in much greater detail. The improved instructions, which are the result of user feed back and incorporate the best practices found by many users, and the additional information on the patterns speed up the fairing process. A checklist of items to prevent or eliminate performance problems resulting from the keel and rudder is included along with other boat preparation details that many people overlook.

Fairing rudders has less impact on performance than the keel, because they are much smaller than the keel, and are made more accurately and consistently. Finally, the rudder angle of attack can be changed to get the desired response, much like trimming a sail, whereas the keels shape must work over all angles of attack. Pre '82 boats had rudders that varied in thickness , but fairing them to the minimum thickness can be time consuming and present structural problems. Boats made after 1985 had more consistent and near minimum rudders. Compukeel™ template Kits and Assembled Templates are available for the J/24 rudder in either the class rule version or a proprietary version. The proprietary version is slightly more stall resistant which can sometimes prove beneficial when close reaching with the spinnaker. Many people find that 80% of the benefit of fairing the rudder can be acheived by simply rounding the leading edge, squaring off the trailing edge and block sanding or filling any waviness or hollows.


The following regatta results demonstrate the significance of the keel on J/24 performance. In a six race regatta, the winning skippers of each fleet (J/24, SONAR, MORC, PHRF, etc.) raced in J/24s to determine the skipper of the year. The nine boats were rotated among skippers after each race. Every race was won by a boat having a keel faired using a template. The top three boats had keels faired using Computer Keels patented templates with an average finish of 3.25. The average finish for the non-Computer Keels faired boats was 5.75. Other Compukeel™ Winning performances
Secure Order form for: Model Number of Keel Sections Compukeel™ Kit Assembled Compukeel™ Templates Compukeel™ II Kit Assembled Compukeel™ II Templates # of Rudder Sections Kit Assembled Rudder Templates
J/24 CKD 6 $235 $535 $375 $675 1 $30 $75
J/24 CRD 6 $150 $450 NA NA 1 $25 $70
USA normal shipping on kits is $15. USA shipping on assembled templates is $45. Rush shipping is available, call for details. Shipping Assembled Templates outside the United States is extremely expensive and or slow. The Template Kit is easily mailable outside the United States for $15US.

If you have any questions, contact us using our on-line inquiry form, write us at COMPUTER KEELS COMPANY, P.O. Box 39757, Edina, MN 55439 or call (952) 829-5670, or e-mail:

Updated August 16, 2005 © 1997-2005 Computer Keels Company All rights reserved ()

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