Specification Report 2001

                                           

 

Spinnaker cloth weight

 

Over the last few of years the question of cloth weight for spinnakers has been raised. The local measurers and boat owners

had no means of knowing the weight of the cloth. To this end. I issued a memo to local sailmakers on February 1/2001

indicating that all new spinnakers must be marked with the weight of the cloth on the spinnaker beside the ISCA label, and sail

cloth weight must also placed on the invoice. This places the onus for certifying sail cloth weight on the sailmakers.

 

 

Measured boats

 

 A list of all boats measured has been distributed to members at the AGM. The list will be posted on the web at a later date.

 

 

 

Recommendations for Specification Amendments

 

 Below are three amendments to specification that the class should look at. Amendment 4.5 is designed to maintain the one

design status of the class. The class is not a development class and the class should make this quite clear.

 

The amendment to the keel section is to accommodate existing conditions already found on all keels.

 

The addition to the rudder section is a safely measure to help prevent rudders from popping off.

 

 

Measurement

 

4.5

 

 a)      A boat cannot be alternated or modified beyond the Designers/Manufactures intent.

 

 b)      If the Specifications do not cover certain applications the boat cannot be altered or modified without the written approval from the Specification Committee.  

 

 c)      Omissions or mistakes in the Specifications shall not be used to one's benefit.

 

 Keel

 

      ·      The thickness of the keel web (flat section) at the fore and aft points shall not be greater than 22 mm (7/8”) or less

         than 16 mm (5/8”).  The thickness must be constant over the length of this section within 6 mm (¼”) i.e. max.

         Allowable thickness at any point of this section is 28 mm (1 1/8”).  The web can be tapered up to a maximum

         50 mm (2") on the forward and trailing edge.

 

  

 Rudder

 

·      The rudder or transom shall be fitted with a suitable means of preventing the rudder from becoming detached

from the hull while sailing. 

 

 

Sails

 

I would recommend the removal of all imperial measurement, as the conversion factors are incorrect. The specifications state the metric measurements are ones that govern measurement and the removal of imperial measurements should in no way affect

the class. This would eliminate the confusion over cloth weight.

 

 

 Mylar Sails

 

Following an inquiry on the use of Mylar sails in the Shark Fleet. I contacted a number of sailmakers for their opinions and perspectives on this issue.

 

The result of this inquiry found three sailmakers opposed to Mylar and one in favour. Factors such as cost and durability were the key issues considered regarding Mylar sails. The range in cost was from 20% less to 30% more for Mylar sails. Durability

would be similar to Dacron.

 

Lack of availability of Dacron cloth was considered an issue by one sailmaker. However, a cloth manufacturer noted that 80% of sails are made of Dacron and that due to this high use, the cloth has undergone many improvements over the past few years.

 

I feel this issue warrants further investigation before the class makes a final decision. I would like more time to consult with sailmakers and cloth manufacturers before I am ready to make my final recommendations.

 

 

Recommendations at this time

 

·       The Shark Class should encourage the sailmakers to test Mylar sails.

 

·       Use of Mylar sails should be limited to club racing, upon approval of the fleet of that club

 

·       Sails cannot be used at major and counter regattas.

 

·       Mylar sails should require some type of identification to indicate they are test sails in order to protect sailors from purchasing used sails in the future.

 

·       The test sails would not be grandfathered into fleet sailing if not approved by the Class.

 

·       Results of testing should be forwarded to the Shark Class.

 

 

 

Jeff Mitchell

 

Saturday, February 24, 2001