IDNIYRA Technical Committee: Sail Material Determination

IDNIYRA Technical Committee Communication
Jeff Kent US3535, Chairperson
Tomek Zakrzewski P55, Paul Goodwin US46, Steve Orlebeke US4926, Richard Larsson S807, Peter Hamrak M53
Date: 2.3.2020
Subject: Sail Material Determination


There has been much recent discussion about what is considered Class-legal sailcloth. It has been a bit frustrating but has provided a great learning experience to for myself and hopefully for most of you. This exercise is very useful, especially since most of the current TC board were not on the board or even sailing a DN when the related specifications or interpretations were initiated.


I will document some of the background history on how the DN Class came come to the current sail cloth specifications. We will enforce the current specifications. Much of this information came from Paul Goodwin, Henry Bossett, Mike Boston, and others. Understanding the background is invaluable for us to know as we move forward.


In simple form: Originally, the sailcloth had to be just Howe & Bainbridge 6.5oz . At that time, all cloth was exported from H&B. US sail makers had the ability to pick and choose the best rolls of material because quality varied dramatically. The European sail makers had the left overs which were inconsistent in quality. This created pressure for the Class to open up to supplier(s) in Europe and the Class added a second construction. Both of these were essentially the same and were of unbalanced weaves.


There came a time when only one sailcloth was available. The TC was asked to consider a new entry, Contender Polykote. This was also an unbalanced weave and essentially identical to the other suppliers. The Class decided to allow this new cloth to provide multiple suppliers.


Only the specific unbalanced construction meets our current DN Class Specifications. This leaves us with 2 Class-legal cloths which have been used for years:
Dimension Polyant      280AP HTP+      250x 410
Contender                    6.5 Polykote      200 x 440


There are now more products that have a name Polykote attached and their construction varies dramatically. Construction of the cloths is much different, is way out of the requirement in our specifications, and is considered not legal for use in competition in IDNIYRA events.


Conclusion: There is no specification change or interpretation required. We will enforce the current specifications. The TC may look into modifying this specification in the future.