Amendments to Class Rules – Sails

Discuss the IOM class rules and interpretations

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David Alston
Posts: 9
Joined: 17 Nov 2016, 23:19
Sail number: 11
Club: Bournville
Design: V9

Amendments to Class Rules – Sails

Post by David Alston » 24 Dec 2016, 13:20

Clearly a great deal of work went into the revision of the Class Rules for 2017 however intent upon clarity and a clean-up seems to have yawed off course somewhat.

Consequently I do agree with John Ball that the revision should be rejected but clearly for differing reasons.

Sails seem to be ever the target of revision , I have not even read the other changes as yet :-

The class rules used to state:-
2016- G3.1(2) The BODY of the sail shall consist of the same ply throughout and of not more than four parts joined by SEAMS.

2017-G3.1(2) The BODY of the sail shall consist of the same ply throughout

By deleting ‘and of not more than four parts joined by SEAMS.’ removes this clear restriction on the number of panels. So one needs to add the following since the is only an implied limitation:-

2017-G3.1(3) The BODY of the sail shall consist of not more than four parts joined by SEAMS.

There is absolutely no need to make a distinction between a single panel sail and a multi-panel sail.

G.4.2 CONSTRUCTION TECHNIQUES
Consider simply stating:-

Three dimensional shape MAY be induced into the sail using any technique

This removes any implied restriction on moulding of sails. There is no point in imposing or allowing any particular method.

2016-G3.1 (3) SEAMS shall not deviate more than 10 mm from a straight line between…

Has simply moved and lost in the verbiage of G4.2.(a) It really belongs where it was as a MANDATORY requirement.

2017 G.4.2 (a) (1) ……. Seams shall not deviate more than 10 mm from a straight line between….



2016 G.4.2 (b) Except for stitching, the joining techniques used at seams shall not extent beyond the edges of the seam.

Has simply moved to G.4.2.(a) (1)

2017 G.4.2.(a) (1) Panelled sails with two or three parts joined by seams which shall not deviate more than 10 mm from straight line between luff and leech. Except for stitching, seam width shall INCLUDE the joining techniques.

However the word SEAM is a defined term:-

ERS G.1.4 (h) SEAM - Overlap where two or more ply forming the body of the sail are joined.

So is BODY

The key word is OVERLAP is so one really cannot use this defined term in this context.

Whilst the intention is to allow a small margin of jointing tape extension beyond the seam one has to specifically state the extension in a Closed Rule environment. i.e. ( not that anyone would make a sail with the sticky tape poking out that much. and anyone who protests the sail should burned at the stake )

The Jointing technique MAY extend no more than XX mm beyond the seam.

What the revision would permit is shown in Attached sketch:-

With the right choice of material............

One sincerely believes this needs a little more work... do you not agree.

cvc
Attachments
Sketch 11.pdf
(11.29 KiB) Downloaded 160 times

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