Revised Text Rules 5,6,7,11,12

Use this forum to discuss the latest changes in the class
Steve Clark
Posts: 165
Joined: Fri Aug 01, 2003 2:26 pm

Post by Steve Clark » Wed Oct 05, 2005 7:28 pm

Well kids, here is the next shot at it.
I have attempted to clear up some ambiguities and correct a few oversights.
Most significantly, I have gone back at the minimum beam/ cross section rule to try to make it clear and bulletproof.
The tight tape rule has been refined. At the beam measurement station, 2 meter tape centered on the measurement station and stretched fore and aft shall bridge no hollows. Thus assuring fore and aft fairness through the measurement point. A 1 meter tape centered on the keel at the measurement atation shall bridge no hollow etc. Thus assuring athwartship fairness. All to avoid bumping. It does however allow 505 or 49er like topsides as long as the beam never is less than 750 100-300 above the keel. All of this in aide of getting the shroud chainplates and seat rails outboard if deemed necessary but making sure it is done in a smooth fluid kind of way.
Which kind of forces us to put a maximum beam out there, So I dug out 1070mm. This being the Max beam under the old development rule.
Hopefully I cleaned up the rig height measurement and the batten issue in sail measurement.
Let me know if this does it.
SHC
New Rules Text

Note:
Unless specifically required otherwise hereunder, all measurements shall be taken parallel to one of the three major axis of the hull - vertical, horizontal or transverse - related to the waterline and fore and aft centre line of the hull
5 HULL
a) The overall length shall be not be greater than 5200mm or less than 4900mm. This measurement shall include any protective strip, and shall exclude rudder and rudder fittings.

b) The projection on to a horizontal plane of the
line of greatest beam shall be a fair continuous curve,
and at bow and stern shall lie inside lines which are
at 45º to the center-line and which pass through the
center line not more than 25mm beyond the extremities.

c) Minimum beam.
The canoe must have a minimum beam of 750mm. Beam shall be measured at a station between 1300mm and 2600mm forward of the stern. Nowhere between the heights of 100mm and 300 mm above the keel shall the outside of the hull skin be less than 750mm in beam.

d) A 2000 mm tape centered on the beam measurement station and pulled tight fore and aft against the outside skin of the hull, shall bridge no hollow in excess of 1mm in depth. A 1000 mm tape centered on the keel at the beam measurement station and pulled tight transversely against the outside skin of the hull, shall bridge no hollow in excess of 1mm in depth.
e) Maximum beam Nowhere shall the outside skin of the hull exceed 1070mm in beam.
e) The hull and all equipment required for
racing, except for sails, battens, clothing, food and
drink, shall be weighed together and dry and shall
have a total mass of not less than 50kg. The mass
of correctors shall not exceed 10kg. Correctors shall
be fastened permanently either to the seat carriage
or to the deck adjacent to the seat carriage and
shall be clearly visible. If fastened to the underside
of the deck a readily removable hatch cover must be
provided to ensure visibility. The hull shall not be
ballasted.
f) There are no restrictions on the material or
method of construction of the hull.
6 DECK
There are no restrictions on the design or material
of the deck other than the rules above.
7 BUOYANCY
Reliable buoyancy to give at least 30kg wt of
positive buoyancy with hull flooded shall be
provided. If the buoyancy is in the form of tanks or
flexible bags there shall be at least two. A sectioned
hull is not acceptable. If the buoyancy is not
removable the builder must certify that such
buoyancy satisfies this rule.

11 MAST, BOOM, RIGGING
a) Any measurement over 50mm
in the fore and aft section of a rotating mast
shall be measured as sail area. This
measurement of area shall be taken between
the upper measurement band and the actual
or projected line of the foredeck. This rule
shall not be applied retrospectively.
b) The width and depth of the boom shall not
exceed 100mm. The width and depth of the
boom of a boomed foresail shall not exceed
30mm. For wishbone booms used for mainsail
and/or foresail each side of a wishbone shall
be measured separately and shall comply with
the same limits.
c) The greatest projected area of spars other
than the mast, boom, jib stick and the boom
of a boomed foresail shall be included in the
sail area.
A jib stick may be used to boom out the
foresail. When in use it shall be fixed to the
mast and attached to the clew.
e) The mast shall carry a permanent band of
contrasting colour approximately 10mm wide
such that the lower edge is 6360mm above the
underside of the hull.
f) No sail shall be hoisted or set more than above 6360mm above the underside of the hull.
g) Outriggers that extend beyond the sheer line
are prohibited.
h) There are no restrictions on the design,
material, or position of the mast and spars
other than the rules above.
12 SAILS
a) The total sail area shall not exceed 10 square
meters. Fairings attached to the sail shall be
measured as part of the sail. Fairings attached
to the mast shall be measured as part of the
mast. It is intended that
the actual projected area of the sails shall be
measured using successive triangulation and
the following procedure: The sail shall have a
tension of 10kg wt on wired and roped edges
and 5kg wt on other edges simultaneously.
Measurements are taken to the outside edges
of sails and to the inner edges of ropes or
wires. Zip fasteners and other devices should
be opened, so that the greatest sail area is
measured.
If a stretch luff is used on a mainsail the luff
measurement will be taken as the distance
between the lower edge of the band on the
mast and the upper edge of the boom, with
the boom at its lowest position if not fixed.
Stretch luffs on foresails must be extended
until the folds in the luff disappear. Each sail,
if not itself of suitable material, must be
provided with an area at least 60mm by 60mm
which will accept a permanent mark or stamp
by the measurer. It must be possible for the
helmsman readily to remove the mainsail from
the mast while the canoe is floating free.
b) Mainsail The battens are to be in place, but
un-tensioned. The main triangle is then
measured. The area of the roach on the leech
is measured by successive triangulation: the
perpendicular of each triangle shall be
positioned at the maximum width of the
segment, except that they shall be positioned
so that the perpendicular of the lower leech
triangle shall not be greater than 150mm. If
the lower part of the leech is straight the
second triangle may be taken to meet the
leech at the upper end of the straight part to
simplify calculation. If the edge of the sail is
curved the area is divided into triangles until
the perpendicular of a segment is less than
150mm; the area of the remaining segment is
taken as 2/3rds chord times width. If the edge
of the sail is straight it shall be divided into
convenient triangles. The areas of the roaches
on the luff and the foot are measured using a
similar method. For sleeve luff sails, the
leading 50mm is considered mast area when
the sail is laid flat for measurement.
The measuring points at the corners of sails
shall be the intersection of the continued
smooth curves of the edges of the sail. To
allow for fullness in the luff and foot of the
mainsail 0.6 square meter is deducted from
the calculated area.
c) Foresail The area is measured by successive
triangulation using a method similar to that
used for the mainsail. Negative areas on the
foot and leech shall be subtracted from the
total area. Positive areas on the foot shall be
included. Positive and negative areas on the
luff shall be ignored.
d) All linear dimensions shall be taken to the
nearest mm. The total area of each sail shall,
after addition of its components be rounded
off to two decimal places (0.01 square meter)
e) Sails must be able to pass through a hoop of
internal diameter 300mm.
f) The mainsail shall carry the letters IC in red,
the national letter or letters and the
registered number allocated by the National
Federation. The national letter or letters and
sail numbers shall be clearly visible, legible
and of a single colour that strongly contrasts
with the sail and in roman style (upright),
without serifs, with arabic numerals and with
lines that are continuous and of uniform
thickness. National letters shall be placed in
front of or above the sail numbers. When the
national letters end in "I" and are placed in
front of the numbers, they shall be separated
from them by a horizontal line approximately
50mm long.
The letters IC, national letter(s) and sail
numbers shall be above an imaginary line
projecting at right angles to the luff from a
point one-third of the distance, measured
from the tack, to the head of the sail; shall be
clearly visible; and shall be placed at different
heights on the two sides of the sail, those on
the starboard side being uppermost. Numbers
and letters shall be of the following minimum
dimensions:
Height: 300mm.
Thickness: 40mm.
Width: 200mm. (excluding number one or letter L)
Space between adjoining letters and numbers: 60mm.
g) There are no restrictions on the design,
material or position of sails, battens, ropes or
wires, other than the rules above.
Beatings will continue until morale improves

Andy P
Posts: 97
Joined: Thu Sep 08, 2005 9:31 pm

Post by Andy P » Wed Oct 05, 2005 8:42 pm

5 a)
No ban on fairings attached to rudder, rudderstock or rudder fittings to extend the hull. Add this ban or someone will do it.

5 b)
"...fair continuous curve..." Fair could be a bit subjective, since the intention is to allow winglets, so the curve could be very wiggly, but continuous, and arguably unfair.
Delete 'fair' ?

5 e) "Correctors shall be fastened permanently either to the seat carriage or to the deck adjacent to the seat carriage "

Assumes a seat carriage...

suggested amendment -
"Correctors shall be fastened permanently either to the seat carriage
or to the deck adjacent to the < SEAT OR > seat carriage.... "


Otherwise an excellent job!

jimc
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Joined: Mon Sep 12, 2005 7:45 pm
Location: United Kingdom
Contact:

Post by jimc » Wed Oct 05, 2005 8:57 pm

> 7 A sectioned hull is not acceptable

I don't know what that means! Does everyone else?


> 11a. any measurement over 50mm...

50mm is quite tight for a rotating mast. Presumably this is by intention. There's a precedent* for having 100mm as the limit without folk feeling obliged to use them. Or of course 75mm would be a compromise.

Good job! For those of you who haven't tried it writing rules is suprisingly difficult. If passed this would be I think the best rise of floor rule on any restricted rule class that I am aware of.

Jim C

*Cherubs, AUS and UK

Andy P
Posts: 97
Joined: Thu Sep 08, 2005 9:31 pm

Post by Andy P » Wed Oct 05, 2005 9:57 pm

Bouyancy - ( only changed the amount of buoyancy from the old rule )
Sectioned hull means tanks or compartments integral with the hull are not counted.

But the foam in the core of foam sandwich is counted.... 7 sq m x 5mm foam = 35 litres, at 75kg/m³ = approx 30 kg of buoyancy!



mast dia
( also unchanged )
most masts are > 50mm dia, but only rotating masts are considered for area measurement- even if they are circular section! A rotating circular unstayed mast might be better a fair bit bigger than 50mm - eg RS 300 mast is ~65mm at the deck, but this has no beneficial aerodynamic effect.

Perhaps this should read ' over-rotating masts '
or increase to 75mm ?

Alistair
Posts: 244
Joined: Mon Sep 22, 2003 7:28 pm
Location: United Kingdom

Post by Alistair » Wed Oct 05, 2005 10:04 pm

7 BUOYANCY
Reliable buoyancy to give at least 30kg wt of
positive buoyancy with hull flooded shall be
provided. If the buoyancy is in the form of tanks or
flexible bags there shall be at least two. A sectioned
hull is not acceptable. If the buoyancy is not
removable the builder must certify that such
buoyancy satisfies this rule.


This just means that you can not rely on the intregrity of yuor hull to comply with the boyancy rule, ie you need foam or seperate bags, I suppose that it is there in case the hull gets holed, its in the present rules and most builders use foam and put it under the decks to help stiffen them up.
Alistair

Steve Clark
Posts: 165
Joined: Fri Aug 01, 2003 2:26 pm

Post by Steve Clark » Wed Oct 05, 2005 10:18 pm

"sectioned hull" has meant containing a watertight bulkhead or two. Idea is to have the flotation actually be different sstructures. In reality almost everyboat built ithe last 10years has had enough core in it to pass this rule.
50mm is the current nominal mast diameter, once they get bigger than that and start to rotate then you have to strt paying for it. This is straight out of the current class rules.
I agree that fences and fairings on the rudders that extend the hull are problematic. Origionally I cribbed and modified language from the A Cats. "Length shall be taken between perpendiculars to the extemities of the canoe in its normal trim and shall exclude rudder fittings. However if the athwartship width of the rudder within 150mm of the bottom of the hull is more than 50mm then the length shall be taken to the aftermost part of the rudder."
This, along with the line of max beam having to intersect within 25mm of the end of the hull I would think would do a pretty good job discouraging most attempts to gain length by nafarious means.
I am tempted to keep "fair" even if it is somewhat subjective. Again the intent is to have undistorted attractive boats and you need something to squash the uglies!
SHC
Beatings will continue until morale improves

tim wilson
Posts: 1
Joined: Fri Aug 20, 2004 6:57 am
Location: Australia

Post by tim wilson » Thu Oct 06, 2005 3:03 am

G'day All
I think its time to scrap the current directions for measuring sails. These rules were written by Noah for hemp-roped cotton sails and bamboo battens. Modern sail material is effectively inelastic, and to measure properly all we need is to ensure the sail is completely flat, by stretching bolt ropes until no cloth wrinkles remain.
From years of experiment in 14' skiffs and more recently in IC's, and cooperation with several sailmakers (who have actual panel areas to calculate total sail areas) the most accurate and repeatable procedure I have found is:

With battens in place as for sailing, tension luff until all traces of wrinkles in sail fabric disappear. This may require tens of kilograms of force. The tension is principally to stretch the bolt rope, allowing the sail to show its actual profile.
Tension a roped foot similarly.
Apply sufficient tension to the leech to ensure the minimum possible wrinkling shows anywhere on the sail. Any remaining wrinkles are from seam-shaping in the sail, cannot be practically removed, and are usually of no significance. (Measurer's discretion must apply.)

The sail can now be measured with the existing technique, without any folding over of the luff, something I've never seen in practice, and certainly not to any of my new and precious sails.

Steve Clark
Posts: 165
Joined: Fri Aug 01, 2003 2:26 pm

Post by Steve Clark » Thu Oct 06, 2005 11:14 am

Tim:
Latest draft calls for battens to be left in place but not tensioned.
This makes the sail measurement essentially identical to ISAF proceedure.
What do you think of the rest of it?
SHC
Beatings will continue until morale improves

Andy P
Posts: 97
Joined: Thu Sep 08, 2005 9:31 pm

Post by Andy P » Sun Oct 09, 2005 8:09 pm

I wasn't going to go into the sail measurements, but since it';s been mentioned ...

These comments refer to the existing rules ( which appear to need a rehash )

It would be more honest to say that the max sail area is 10.6 sq m, instead of the 'allowance' of - 0.6 sq m to make it 10 sq m.
There may be historical reasons for this, but it's actaully not a " 10 sq m " int canoe any more, however it's described.

The 10kg / 5 kg tension on the edges is different from the IYRU/ ISAF system that requires the sail pegged out with battens tensioned -
' With battens set in their pockets the sail shall be pegged out on a flat surface with just sufficient tension to remove waves or wrinkles from the edge rounds and to spread the sail, as far as possible, substantially flat'

I have measured many moth sails like this, and this method accounts for the different stretch in bolt ropes / sleeve luff sails in a fair repeatable manner.( and avoids rule-cheaters with tight bolt ropes.) The batten tension changes the shape and individual measuremements on a sail, but the end result is the same.


Are current fixed masts less than 50 mm? ( the superspar masts used in UK are nominal 55mm dia internal , + track = 70mm fore and aft.)

Why should a rotating round mast ( of > 50mm ) get a penalty?

Roland Whitehead
Posts: 15
Joined: Mon Oct 10, 2005 8:43 am
Location: United Kingdom

Post by Roland Whitehead » Tue Oct 11, 2005 11:08 am

What does "It must be possible for the helmsman readily to remove the mainsail from the mast while the canoe is floating free." actually mean. The Sweedish camber batterned sails of the early 90's had all sorts of issues with this as they acutally rigged the boats on their side. To cope they had to have velcro or a zipper (can't remember which) up the front of the mast.

If you have a sleeved luff and have rigged it by pulling the sleeve over the top of a tube mast, a) how do you paint the band and b) can you capsize the boat to remove the mainsail from the mast when its floating free? Alternatively could you just remove both the band issue and the readily removable issue. Hey, I might want to put on a solid wing....

Couldn't you leave all the sale measurement issues to the standard ISAF sail area measurement document and simplify the rules as much as possible.

Footnote: Perhaps this is a hint of another C class person returning to the IC fold. It looks like I'm heading back to Hayling Island next year (assuming I can mortgage the house to pay for the entry fee's). I'm not that keen on the AC's and would much rather build something a little more open. Its either that or admitting that I'm past it and going slower with lots of lead.

Andy P
Posts: 97
Joined: Thu Sep 08, 2005 9:31 pm

Post by Andy P » Tue Oct 11, 2005 7:52 pm

I guess that zips would be required to remove sleeve luff off shroud/spreader type rig.
Windsurf style unstayed is also hard to get off the mast, and would need zips.
'Floating free' - capsized and floating meets the rule.

A solid wing counts as mast, so this rule does not apply.

Phil Stevenson
Posts: 202
Joined: Wed Sep 07, 2005 9:54 pm
Location: Australia

Post by Phil Stevenson » Tue Oct 11, 2005 10:16 pm

I just re read the proposed rules after all the discussion on this and other threads about sailboard sails.
There appears to be no rules which would stop anyone building a long narrow hull and sailing it like a sailboard, standing up and holding the rig.
20 odd years ago the moth class saw this potential as a threat and banned the idea with a specific rule because they saw that it would substantially change the way the class was sailed.
Do the canoe people see or fear a similar threat? and is a rule required to cover the potential?
Design perfection is achieved, not when there is nothing else to add but when there is nothing else which can be taken away.
http://philscanoes.blogspot.com/

Steve Clark
Posts: 165
Joined: Fri Aug 01, 2003 2:26 pm

Post by Steve Clark » Wed Oct 12, 2005 12:18 pm

Phil,
I think the minimum weight and hull form rules are pretty good barriers. Having attempted to use a ailboard rig on various types of open boats and dinghies, I can assure you that standing on an IC and trying to hold onto a 10m^2 rig is damn near physicly impossible, The boat weighs too much and the loads are may way higher than on any sailboard.
This is different from Moth, so I don't think it really is a risk.
SHC
Beatings will continue until morale improves

Chris AUS 11
Posts: 0
Joined: Sun Jul 20, 2003 4:44 am

Post by Chris AUS 11 » Wed Oct 12, 2005 8:24 pm

I don't think the weight and sail size would necessarily stop a windsurfer-style IC racing. Longboards like Mistrals are something in the region of 25kg as they would be measured here, the original Windsurfer OD is heavier still. Perhaps the best example is the old tandem course-racing boards which would have been shorter (about 15-16' IIRC) and heavier (with crew included) than an IC and carried 13.6m of low-aspect "pinhead" sail in a cat ketch rig, but were probably quicker than an IC. Even a single sailor can handle round-bottomed boards of about 15' long and they were proven quicker than the C 12' boards until they were banned.

I'm not sure the shape restriction is a problem, and 10m2 is pretty easy to handle - the only problem being that powerful rigs get difficult and easy rigs are gutless.

I think experience in Moths shows that boards of equivalent weight and SA are faster, and there is a chance to build something interesting here - but IMHO it wouldn't be an IC. So it may be a good idea to ban boards, or at least discuss them.

Mal Smith
Posts: 79
Joined: Mon Dec 20, 2004 1:42 am
Location: Australia

Post by Mal Smith » Fri Oct 14, 2005 3:10 am

Regarding the minimum beam rule, given that there is likely to be a range of station positions that will satisfy rule 5c, how is the station position nominated for the purpose of rule 5d (the tight tape rule)? Is it good enough to say that if a station position can be found which satisfies both 5c and 5d, then the hull measures in? If so, could this be clarified in the wording?

Regarding the sliding seat/trapeze debate, I take it form the proposed wording that trapezes, if not specifically banned, are certainly not encouraged (due to the maximum beam and no outrigger rules). Is that correct?

Regarding the mast measurement rule, is a sail track which is either fixed to, or integral with the mast section counted within the 50mm dimension (rule 11a)? I could imagine that a circular section mast with an external bolt rope track could easily exceed the 50mm, yet the bolt rope, which I presume is also measured as part of the sail area, is going to be contained inside the bolt rope groove. It just seems to make the measuring complicated, and could become a bone of contention. I also feel that, for simplicity, there should not be any differentiation between rotating and non rotating masts. I would favour a more generous allowance, say 75mm, and a simple hoop rule i.e. “the mast section should be capable of passing through a 75mm diameter hole”.

Mal Smith.
AUS019

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