6 SAIL

6.1 General

6.1.1

Anything not specifically permitted by these rules is prohibited, see also CR. 1.2.

6.1.2

Sails shall be made and measured in accordance with the current ISAF "Equipment Rules of Sailing" except where varied herein. Where a term defined or measurement given in the "Equipment Rules of Sailing" is used in these rules, it is printed in "italic" type.All measurements shall be taken along the surface of the sail and include any bolt rope and tabling. Battens shall not be removed for sail measurement purposes.

6.1.3

The manufacturer of sails is optional.

6.1.4

The thickness in mm of the body of the sail shall be indelibly marked by the manufacturer, together with his signature, stamp, and date near the peak point. The thickness of the woven ply of the body of the sail (finished product) shall be checked according to ISAF current instructions.
The thickness of the body of the sail shall be not less than 0.15mm.

6.2 Mainsail

6.2.1 Construction

6.2.1.1

The construction shall be: soft sail, single ply sail.

6.2.1.

The body of the sail shall consist of the same woven ply throughout. The ply fibres shall be of polyester or cotton.

6.2.1.3

The sail shall have two batten pockets in the leech. Local widening for batten insertion (if any) shall be on the upper edge of the batten pockets.

6.2.1.4

The following are permitted: stitching, glues, bolt ropes, batten pocket elastic, one trapezoidal window, sail maker label, sail button(s), tell tales.
Reinforcements shall be of the same woven ply as the body of the sail. Edges of secondary reinforcements shall be fixed by a maximum of two lines of stitches or bonding agents. Parallel or nearly parallel lines of stitching or bonding agent used elsewhere in the secondary reinforcement shall be more than 40mm apart. If two rows of closely positioned stitching are used to fix the edge of the secondary reinforcement then any inner lines of parallel stitching shall be more than 40mm distant from the inner line of edge stitching.
Further to CR. 1.2 and 6.1.1, the following are prohibited: carbon fibres, titanium.

6.2.1.5

Wire or elastic cord shall not be used in the sail. Any bolt rope or tabling used to strengthen the luff or head of the sail shall be fastened to the sail throughout its entire length. If a bolt rope is enclosed in the tabling, it shall be sewn to the sail by visible stitches at those corners of the sail to which the rope extends.

6.2.1.6

On sails first measured after 1 March 1994 there shall be 8 eyelets in the foot of the sail, including those at the tack and clew.
On sails first measured after 1 March 1994 there shall be 8 eyelets in the luff of the sail, including those at the throat and tack. (See also CR. 6.2.2 for spacing between eyelets in luff and foot.)

6.2.2

6.3 Spare number

6.4 Spare number

6.5 Class Insignia, National Letters and Sail Numbers, Luff Measurement Band

6.5.1

The class insignia, sail numbers and letters as issued by the National Authority shall be in accordance with current RRS, except where varied herein.

6.5.2

Numbers and letters on sails first measured after 1 March 1994 shall be of the following dimension (see also Sail Plan sheet 4/5)

		minimum	maximum
1	Height	230 mm	240 mm
2	Width (except "1 " or "I ")	150 mm	160 mm
3	Width for M and W	160 mm	170 mm
4	Thickness	30 mm	40 mm
The national letters shall be placed on the same line on opposite sides of the sail with the letters on the starboard side of the sail closer to the luff than those on the port side of the sail.(see also Sail Plan sheet 4/5).The numbers shall be placed in two rows below the letters with the starboard side numbers uppermost. The following spacing shall apply:
		minimum	maximum
5	Space between adjoining numbers or letters	40 mm	50 mm
6	Space between rows of numbers or letters	40 mm	50 mm
7	Space between the national letter groups on opposite sides of the sail	100 mm	150 mm
8	Distance between the luff and the closest letter or number in each row	150 mm
9	Distance between lower edge of uppermost batten pocket and the national letter which is closest to the leech	40 mm	50 mm

6.5.3

The class insignia shall conform with CR. 2.7.1, and have dimensions and requirements as detailed in the Sail Plan sheet 4/5. On sails first measured after 1 March 1994 no part of the class insignia shall extend beyond 1000 mm of the peak point. The class insignia shall be placed back to back on both sides of the sail.

6.5.4

The sail shall have a sail measurement band on its luff (luff measurement band). This band, of a colour that strongly contrasts with the sail, shall be permanently fixed or marked on both sides of the sail. It shall be perpendicular to the edge of the luff of the sail, and shall start at its edge. See CR. 6.2.2, Sail Plan, Rigging Plan sheet 12/12, for position and dimension of bands.

6.6 Additional rules

6.6.1

Only sails endorsed in accordance with CR. 2.5.6 shall be used.

6.6.2

The manufacturer of sail battens is optional. The construction material is optional except that Carbon fibre is prohibited.

6.6.3

Fastening and positioning.

6.6.3.1

The upper edge of the luff measurement band shall not extend above the lower edge of Band No. 1, and the lower edge of the luff measurement band shall not extend below the upper edge of Band No. 2. At the throat, both mast holes or lacing eyes referred to in CR. 3.5.2.6 shall be used to prevent any part of the luff measurement band rising above the lower edge of Band No. 1.

6.6.3.2

No part of the clew point shall extend beyond the inner edge of the boom band.

6.6.3.3

The luff of the sail shall be lashed to the mast at each eyelet so as to be within 10 mm of the mast.

6.6.3.4

The foot of the sail shall be lashed to the boom at each eyelet so as to be within 10 mm of the boom. Alternatively, at the tack eyelet, it may either be lashed to the jaw fittings or attached through two holes in the jaws or jaw fittings, so as to be within 10 mm of the boom or its imaginary extension (see also Rigging Plan sheet 12/12).

6.6.3.5

The sail shall be fastened to the mast and boom with cordage only.

6.6.3.6

The peak of the sail shall be fastened to the upper end of the sprit either by means of an eyelet at the peak, or by means of a loop made of tape or rope sewn to the peak.

APPENDIX A

CLASS RULES SPECIFIC TO WOOD AND WOOD/EPOXY HULLS

2.5.1

Only a measurer officially recognised by a National Authority shall measure a hull, spars, sails and equipment, and sign the declaration on the measurement form that they comply with the class rules. Hulls shall be measured in accordance with the appropriate hull measurement instructions. After the measurer has signed the measurement form, he shall affix the ISAF plaque to the mast thwart bulkhead as per CR 2.7.2.

2.5.4

All hulls shall comply with the current rules or the rules current at the time the boat was first measured. Hulls first measured between 1 March 1997 and 1 March 1998 shall conform either to the class rules in force from 1 March 1995 or the class rules in force from 1 March 1997. Hulls first measured after 1 March 1998 shall conform to the class rules then current. Fittings, spars, sails and other equipment shall comply with the current rules unless otherwise stated in the specific class rule referring to such equipment.

3.2.1 Materials - WOOD AND WOOD/EPOXY

3.2.1.1

The hull shall be constructed of materials approved by the ISAF. The following are the currently approved materials:wood.

3.2.1.2

Hulls shall be constructed from:

Wood
Commercially available plywood, of marine or other water proof grade suitable for boatbuilding	Plywood of 6mm minimum nominal thickness and weighing not less than 2kg/m2 shall be used, except that thinner plywoods may be used for doubling pieces and in construction of the hull bottom. (see Plan sheets).
Glue - Epoxy resin for bonding
Glass tape and metal fasteners

The builder shall on request supply a sample and specification sheet of any plywood used.

3.2.2.1

The dimensions of the hull shall be as shown on the plans and as given in these rules, diagrams and measurement form and shall conform with the tolerances stated therein.

3.2.2.5

The overall length excluding rudder fittings, shall be 2300mm +/- 12mm, measured at the sheerline.

3.2.2.9

The forward and aft transom shall be flat with not more than 5mm tolerance.

3.2.2.10

The inside of the daggerboard case and of the slot in the hog and bottom panel shall be 330mm +/- 5mm. The ends in the daggerboard case slot shall be parallel and square to the base line. A rake to taper not exceeding 5mm is permitted. The upper edge of the daggerboard case shall be parallel to the base line, with a tolerance of 5mm maximum.

3.2.2.11

The inside width of the daggerboard case and the slot in the hog and bottom panel shall be 17mm +/- 1mm. The fore and aft ends of the slot shall be semi-circular in cross section.

3.2.2.12

The outside edges of the hull between bottom and side panels, between the bottom and forward transom, and between the side panels and forward transom shall be rounded to a radius of 4+/-2mm. At the aft transom side and bottom outside edges no radius is permitted.

3.2.3 Wood and wood/epoxy Hull Construction Details

3.2.3.1

There shall be a mast thwart positioned as shown on the plan. It shall be 195mm +/- 5mm wide and not less than 16mm nor more than 25mm thick.

3.2.3.2

There shall be a mast thwart bulkhead fixed to the aft side of the mast thwart, and in wooden hulls to the side pieces secured to the side panels, as shown on the plans.

3.2.3.3

There shall be a midship frame positioned as shown on the plans with limber holes in the positions shown.

3.2.3.4

The shape of the hole in the mast step is optional. (See also rule 3.2.6.1(f)).

3.2.4 Construction Details - Wood

3.2.4.1 Hulls of Traditional Wood Construction

(a)

The hog, stringers and chine shall be of wood bonded to the inside of the bottom panel. they shall each be of uniform thickness and shall each be of uniform width:

(i) for the hog min 16 x 100mm min
(ii) for the stringers chine and gunwale 16 x 35 mm min

.

(b)

The scantlings for the frames, hog, stringers and chine shall be complied with but exposed corners, except for the gunwale (see rule (i) below),may be rounded to a maximum radius of 5mm.

(c)

not used in this version

(d)

not used in this version

(e)

The midship bottom frame and the daggerboard case sides shall be of plywood with a nominal thickness of 12mm.

(f)

As optional construction. the bow and aft transoms shall be of plywood with a nominal thickness of min. 6mm and max. 12mm.

(g)

The bottom and side panels, knees and mast thwart bulkhead shall be of plywood with a nominal thickness not less than 6mm.

(h)

The bottom and side panels shall each be of the same nominal thickness throughout.

(i)

The exposed edges of the gunwale stringer and the rubbing strake shall be rounded to a radius of not less than 5mm.

(j)

The knees at the transom may be inset so that their upper surfaces are level with the top of the gunwale stringers.

(k)

Exposed edges of plywood may be capped with solid wood or plywood. The depth of the capping shall not exceed the thickness of the plywood being covered and its width shall not exceed the width of the part of assembled parts being capped.

3.2.4.2 Hulls of Wood/Epoxy Construction

(a)

The hog and stringers shall be of plywood bonded to the inside of the bottom panel. They shall each be of uniform thickness and shall each be of uniform width:

(i)

for the hog not less than 180mm wide;

(ii)

for the stringers not less than 70mm wide, except forward of the mast thwart bulkhead where they may be tapered to conform to the shape of the bottom panels.

(iii)

the thickness of the bottom panel and hog or stringers together shall be not less than 15mm

(b)

Alternatively the bottom may be constructed of one or more sheets of plywood with a total uniform thickness of not less than 15mm. When such a construction is used, hog and stringers are not required.

(c)

The scantlings shown on the plans for the frames, hog and stringers shall be complied with but exposed corners, except for the gunwale(see rule (f) below), which may be rounded to a maximum radius of 5mm.

(d)

The bottom panel shall either be stitched to the side panels and transoms with copper wire at spacing of not more than 60mm, and/or glued with epoxy glue. The joints may be taped inside and/or outside with glass tape and resin.

(e)

Joints between midship frame and bottom panel, midship frame and the sides shall be taped with glass tape and resin or glued with epoxy glue fillets.

(f)

The midship bottom frame and the daggerboard case sides shall be of plywood with a nominal thickness of 12mm.

(g)

As optional construction. the bow and aft transoms shall be of plywood with a nominal thickness of min. 6mm and max. 12mm.

(h)

The bottom and side panels, knees and mast thwart bulkhead shall be of plywood with a nominal thickness not less than 6mm.

(i)

The bottom and side panels shall each be of the same nominal thickness throughout.

(j)

The exposed edges of the gunwale stringer and the rubbing strake shall be rounded to a radius of not less than 5mm.

(k)

The knees at the transom may be inset so that their upper surfaces are level with the top of the gunwale stringers.

(l)

Exposed edges of plywood may be capped with solid wood or plywood. The depth of the capping shall not exceed the thickness of the plywood being covered and its width shall not exceed the width of the part of assembled parts being capped.

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PLANS - The following are the current official plans: (Wood and GRP)
New GRP Plans	March 1995 Amended 1996
Traditional Wooden Plans	March 1997
Wood/Epoxy Plans	March 1997
Rigging Plan	March 1991 Amended 1994
Foil Plan	March 1992 Amended 1994
Sail Plan	March 1994

© 2000 Sail International Limited

Effective:1 March 2001

Last Issue:1 March 1997

Plans and Rules are available from IODA

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