12 Foot Cadet Dinghy - Plans, Specifications and Rules

Transcription

1 12 Foot Cadet Dinghy - Plans, Specifications and Rules (V /09/2009) 1 Document Control Class Title Australian 12 Foot Cadet Dinghy 12 Foot Cadet Dinghy - Plans, Specifications and Rules Description This is the written specification of the wooden and fibreglass hulls, the fittings, the lug rig including spars and rigging, the lugsail, the jib, and the spinnaker. Version V2.01 Status Comments Document History Final Further details are contained in the following documents: Hull Plan - Wooden Dinghy, Plan - Details of Fittings, Proposed Bermudan Rig Plan, Sail Plan - Lugsail and Jib, Sail Plan - Bermudan Mainsail, Sail Plan - Spinnaker, and Equipment Restrictions Applying to Stonehaven Cup Contests. Readers should note that the National Measurer is (as at 13/10/2009) part way through a process of updating the specifications for the class, including metricating the measurements, integrating the specification of the bermudan rig, providing measurement guidance to clarify exactly how particular sails are to be measured, editing the text to make it internally consistent, and re-numbering the sections. Ver Date Person Responsible Details / Comments /08/2002 Frank Pound Incorporated previously agreed changes. Added details of new spinnaker, including sail plan /09/2009 Joe Wilding Removed spinnaker sail plan to a separate document as per other plans. Removed section on restrictions applying to Stonehaven Cup contests. This now forms a separate document.

2 12 Foot Cadet Dinghy - Plans, Specifications and Rules (V /09/2009) 2 These Plans, Specifications and rules may be reviewed annually by the Trustees after application to the Australian 12 Foot Cadet Dinghy Yachting Council, from any competing Yacht Clubs. THE CLASS 1. The Dinghies are a one-design Class and are to be built strictly in accordance with the Plans, Specifications and Rules in order that all boats are, as nearly as possible, identical. MOULDS 2. The moulds are to be carefully laid off from the offsets as shown on the body plan. If there is no bevel cut on the moulds, the after edge of the mould is to coincide with the stations as shown in the body plan in the after body. The forward edge of the mould is to coincide with the stations in the forebody. The position of the midship mould is to be taken at the centre. 3. The Keel is to the following spring from L.W.L. to rabbet Transom at L.W.L. No. 1-2 ¼ No. 2-4 ½ No /8 th No /8 th No. 5-3 ¾ INSPECTION DURING CONSTRUCTION 4. During the construction of the hull two inspections are to be made by an Official Measurer. The inspections will be made as follows: 1 st. Inspection After moulds have been placed in position and prior to planking being commenced. 2 nd. Inspection Immediately after the moulds have been withdrawn after planking. 5. The Builder is required to have the Official Measurer s agreement before proceeding further after inspection. 6. Failure to comply with the foregoing will render the dinghy liable to rejection. 7. All materials unless otherwise specified in hulls and spars to be of solid materials. 8. Where radii is not specified it shall not exceed one-eighth of an inch. METHOD OF CONSTRUCTION 9. Type All boats are to be built on the clinker method having eight or nine. strakes a side.

3 3 10. Planking. Planks are to be carefully fitted and well fastened with one 14 gauge copper nail through the timber and lands of each plank and two copper nails through land on each plank between timbers. All copper nails to be clenched with 5/16 diameter roves. The use of glue as a waterproofing agent in addition to the prescribed nail fastening is optional. 11. All planks are to be in one length; the breadth of the landing at each plank is not to be less than three-quarters of an inch and the finished planks are not to be less than threeeights of an inch in thickness. In the case of a repair the section of planking may be replaced without contravening the foregoing. 12. A sliver strake is to be fitted from stem to stern in one or two pieces three-eights of an inch in thickness and of the same material as used for the planking. The sliver strake must land on the top edge of the second plank and run from stem to inside of transom. TIMBERS 13. The timbers are to extend from gunwale to gunwale, except in the way of the centre case and are to be sided one inch and moulded one half inch; the timbers will be spaced at seven inch centres and be notched one quarter inch at each end of the centre. A maximum rounding of one-eighth of an inch side and face on the inside corners of timbers is allowed. 14. There will be twenty timbers in all boats built after 1 st. October RISING 15. The rising is to run fore and aft from the stem to the transom forming a seating for the thwarts and is to be six inches down from the gunwale. It will be sided two inches and moulded one half inch. Rounding one eighth inch side and face shall be allowed. CENTRE BOARD CASE 16. The sides of the centre board case are to be finished to a thickness of one inch, glued and screwed to the keel. The slot of the case will not be less than one half inch wide throughout. 17. Chocks at end of the case are to be made of timber and be at least two and a quarter inches wide and extend to the top side of the thwarts and be securely fastened to the thwarts. The side of the centre case may be extended to the after end of the centre thwart. 18. The centreboard or plate is to be made of three sixteenths of an inch mild steel or alternatively, of eight millimetres (five sixteenths of an inch) high tensile grade T321 aluminium alloy, made to the dimensions of the plan. The mild steel plate may be either galvanised or painted, but not fibreglassed or sheathed in plastic. The mild steel or aluminium alloy plate can be radiused around the perimeter with a radius not exceeding half the plate thickness. The aluminium alloy plate may be tapered along the long rear edge for a width of 25mm from the thickness of 8mm to 2mm.

4 A maximum of five holes is permitted to provide adjustment for partial depth of protrudance of plate as show on the plan The depth of protrudance of the centre board from the garboard plank is NOT to exceed two feet ten inches (2 10 ). The fore and aft orientation of the plate profile in the centre board case is optional. GUNWALE 20. The gunwale which may be built up of laminations is to be sided one and three-quarters of an inch and moulded one and a quarter inch and be fastened through each thwart knee timber. 21. The gunwale may be hollowed on the underside from the radius. 22. The outer moulding is to be not less than one inch diameter rounding and is to be faired back to the full thickness (1 ¼ ) at the planking. THWARTS 23. The width and position of the thwarts which are to be double dressed are as shown in the plans. They are to be double kneed with either: (a) (b) (c) (d) natural grown knees knees cut from straight timber and filled with steam bent facing pieces built up bondwood thoroughly waterproofed, or timber strips laminated to form a curve. 24. Thwarts are to be not less than seven-eigths of an inch thick when finished and are to be well housed on the rising at the mast. A five-sixteenth metal bolt may be fitted through the thwart to the keel forward of the centre board case. BILGE STRINGERS 25. Bilge stringers one and a quarter inches by three-quarters of an inch are to be fitted in position as shown on the plan and are to form a margin for the floor boards. FLOOR BOARDS 26. Floor boards are optional. 27. All floor boards if fitted are to be portable and be secured with beckets, toggles or screws. BAILING STRIPS 28. A maximum of 5 bailing strips no greater than one inch half round metal (non-ferrous), or flat alloy or synthetic material not wider than one inch may be fitted. CHAFING STRIPS 29. Metal keel chafing strips may be used. When used the strips will be of half round metal (non ferrous) not exceeding three-quarters of an inch (3/4 ) in width.

5 MAST STEP 5 30 The mast step is to be fitted to the keel at the forward end of the centre case and be securely fastened with copper nails clenched over roves. 31 In new boats the mast step shall be constructed to the specifications of the Recommended Alternative of Plate Case construction as shown on Details of Fittings Drawing. BREAST HOOKS 32 The breast hook may be of natural grown timber or bondwood or be cut from straight timber and fitted with a steam bent facing piece, sided one inch, moulded as shown on the plan and carefully fitted to the stem. FITTINGS 33 A chain plate will be fitted on each side at the after knee of the mast within seven inches of that knee. Chain plates must be through fastened to the sheer strake. 34. Chain plates may be fitted either inside or outside the planking. 35 Spars, horse, rudder and metal work as per the detailed plan. (a) Horse may be made in stainless steel (b) Rudder blade made from: Timber one inch thickness or Plywood three quarters of one inch thickness (c) Metal fittings to detailed plan or suitable equivalent fittings 36 Rowlocks, chock and plate are optional fittings. If fitted, they will be positioned seven inches aft of the after edge of the centre thwart on each side to take seven-sixteenths of an inch rowlocks. SAILS 37 The total permissible sail area is as detailed in the sail plans with the sails pulled hand tight. 38 Sails will be made of woven synthetic material. Imported sail cloth may be used but the sails must be made in Australia. 39 The minimum weight for sail cloths are as follows: Sail U.S. Imperial Equivalent Units Units Metric Units (a) Mainsail 3.8 ounces 4.8 ounces 164 grams per and Jib (36insx28.5ins) per sq. yard sq. metre (b) Spinnaker 0.75 ounces 0.95 ounces 32 grams per (36insX28.5ins) per sq. yard sq. metre 40 The width of cloths in the mainsail and jib shall not be less than 300mm.

6 41 The following rules will apply to sails: 6 (a) (b) Three battens may be used, placed at ninety degrees to the leach. The maximum length of the battens are as shown on the sail plan. Centre of batten pockets in mainsail to be located at (4 ) four feet, (8 ) eight feet and (12 ) twelve feet from head down leach. A tolerance of (2 ) two inches each side of these locations is allowed. Maximum width of batten pockets is (1 ½ ) one and one half inches. Panels 1. Mainsail panels shall be transverse 2. Panels in the Jib are optional 3. The size and cut of the Spinnaker panels is optional. The sail may have a centre seam. (c) Seams Seams may be either tapered or parallel. (d) Darts 1. Darts are permitted as are leach lines in the mainsail. 2. Adjusting methods of setting sails such as zip panels and adjustable wire luffs are not permitted. (e) Wire Luff Ropes Stainless steel, plastic wrapped, may be used in the mainsail and jib. Non-stretch tape may be used in lieu of rope in the sail construction. (f) (g) Jibs shall have a wire luff rope. Mainsail shall have a minimum of ten eyelets spaced along the gaff and nine eyelets spaced along the boom for mandatory lacing of the mainsail to the gaff and boom. Lacing tension is optional (a) Spinnaker (Approved August 2002) A new (larger) spinnaker has been approved for use from August This shall henceforth be referred to as the 2002 spinnaker. The existing spinnaker shall no longer be permitted for use in interstate class racing on and after the 1 st. October, (b) The 2002 spinnaker shall be a three cornered sail symmetrical about its centre line and shall comply with the measurements on the measurement diagram (c The luffs and the foot shall be taped with a minimum tape weight of 1.5 ounces U.S. (36 x 28.5 ) (1.9 ounces per square yard (imperial) or 65 grams per square metre (metric)) (d) No headboards or clew boards are permitted (e) Measurements on the centrefold shall be taken with tensions applied at the head and centre of the foot sufficient to remove the wrinkles across the line of measurement.

7 RIGGING 7 42 The following conditions will govern the rigging (a) Main Shrouds Port and Starboard main shrouds will be of galvanised plough steel or stainless steel rigging wire, or laid or solid wire fitted with suitable thimbles. The method of attachment to the chain plate is optional except that rigging screws or other devices must be securely locked and shall not be adjusted while racing. Hi-field levers and similar quick release adjusting devices which can be released while racing are not permitted. (b) Wire Halyards Wire halyards with falls may be used, with the fall roves being direct or as a purchase. (c) General (1) A downhaul must be fitted to the boom. A boom vang may be fitted. (2) Cord or rigid tiller extensions may be fitted. (3) The use of banking out straps is permitted. (4) Stops may be fitted to the horse. (5) Roller furling equipment will not be permitted. (6) All blocks used will be of a size which will permit sheets and halyards to run freely. (7) Jamb cleats and one snubbing winch are permitted. (8) Grooves not exceeding twelve inches (12 ) in length may be cut into boom and gaff for setting the mainsail. (9) Sail tracks not exceeding twelve inches (12 ) in length may be used on the outer end of boom and gaff for sail adjusting. (10) Jib luff and mainsail foot tensioning is permitted. (11) Mainsail foot and gaff section of luff must be laced to boom and gaff. Lacing tension is optional. (12) One only main, jib and spinnaker halyard is permitted. (13) Method of sheeting used for mainsail, jib or spinnaker is optional

8 SPARS 8 43 The following are the specifications relating to Mast and Spars which may be either alloy or timber: (a) Timber Spars are to be made of silver spruce or clear oregon pine, and are to be to the detailed plan. The Spars may be solid or hollow and may be laminated in two or more sections. To facilitate repair of damaged Spars, a coating of fibreglass or carbon fibre material may be applied to Spar. Coating thickness shall not exceed 1.5mm and shall not cover more than 50 percent of the Spar surface. (b) Alloy 1. Mast, gaff, boom and spinnaker boom to be parallel for whole length. 2. Mast Mast material to be minimum of 60mm outside diameter with minimum wall thickness of 2mm. Mast may be fitted with wooden filler piece at contact points (length optional). 3. Boom Boom material to be minimum of 51mm outside diameter with minimum wall thickness of 2mm. Boom may be fitted with sliding gooseneck. 4. Gaff Gaff material to be minimum of 51mm outside diameter with a minimum wall thickness of 2mm. Gaff may be fitted with wooden filler piece at contact points (length optional). 5. Spinnaker Boom Spinnaker boom material to be a minimum of 38mm outside diameter with a minimum wall thickness of 1.6mm. (c) Mast 1. All boats built after 1967 must have the alternate method of plate case construction. 2. Where the mast step is built up and extended along the keel for additional strength the height of the centre line of the sheave of the mast above the top of the keel must not exceed (11 10 ½ ) eleven feet ten and one half inches. (d) Boom The length of the boom from the mast to the end of the boom must not exceed (10 4 ½ ) ten feet four and a half inches.

9 (e) (f) Spinnaker Boom The Spinnaker Boom must not exceed (7 6 ) seven feet six inches in overall length including end fittings. Gaff 9 The gaff will be a maximum length of (10 9 ½ ) ten feet nine and one half inches from centreline point of attachment to the end of the gaff. The position of the holes is optional. 44 Spars will be marked with a black painted half inch band as follows: (a) Gaff (10 6 ) Ten feet six inches from the fastening bolt. (b) Boom (10 ) Ten feet from the point of attachment of the sail. 45 Sail tracks are NOT permitted except as specified in 42 (c) 9 WEIGHT 46 The minimum weight of a Cadet Dinghy will be (231) two hundred and thirty one pounds including: (a) Floor boards, if fitted (b) Screwed fittings and horse (c) Bowsprit and bobstay (d) Buoyancy of at least the minimum as specified in paragraph 65 (e) Banking out straps 47 Where a Cadet Dinghy weighs less than the minimum weight of (231) two hundred and thirty one pounds, corrector weights of jarrah or other suitable timber will be fixed to the centre thwart not nearer to the centre line than (12 ) twelve inches from the stringer to bring the dinghy to the specified weight. MEASUREMENT CERTIFICATE 48 When completed the boats are to be measured by the Official Measurer of one of the following Clubs: Royal Brighton Yacht Club Royal Yacht Club of Tasmania South Australian Cadet Dinghy Council 49 The Measurer will use the standard form of measurement and instructions to Measurers, and certify to the correctness of the measurements shown and to the boat s conformity to the Plans, Specifications and Rules. 50 If in the opinion of the Measurer the dinghy has not been built in the spirit of these Plans, Specifications and Rules a Certificate of Registration must not be issued.

10 10 MATERIALS 51 Boats may be built of any suitable solid timber other than plywood except where specified. TABLE OF LIMITATIONS AND TOLERANCES 52 Limitations or tolerances as shown hereunder will apply: (a) (b) Length overall plus or minus (1/2 ) one half inch Half breadths at D.W.L. Stations 5 and 4 plus or minus (3/4 ) three-quarter inch Stations 3,2,1 plus or minus (7/8 ) seven-eights inch. (c) (d) Spring of Keel plus or minus (3/8 ) three-eighth inch. Beam Stations 5,4 & 1 Plus or minus (1/2 ) one half inch 54 Venturi Pumps Stations 2 and 3 Plus or minus (5/8 ) five-eighth inch Two only Venturi Pumps attached in the garboards may be used in the Contests. 55 Trapeze No trapeze of any type will be permitted in the Contests. 56 Bowsprit The maximum length of the bowsprit from the front of the stem to the centre of the outer jib attachment eye is (2 5 ) two feet five inches. SAFETY REGULATIONS 57 All Cadet Dinghies shall comply with current Australian Yachting Federation Yacht Racing Rules, Addendum B, A.Y.F. Safety Regulations, Part 2, Off The Beach Yachts. Not withstanding compliance with these Safety Regulations, the following requirements are mandatory under these Plans, Specifications and Rules. 58 Towing Eye A towing eye or ring constructed of stainless steel with a minimum thickness of 5/32 inches (4mm) and not less than 1 ½ inches (38mm) internal diameter shall be attached to the front of the stem.

11 59 Halyards 11 Mainsail and jib halyards shall be of sufficient length to allow for lowering of sails to facilitate disconnection of halyards from spars and sails when dinghy is submerged. 60 Centre Board 61 Bailer Centre board shall have a lanyard or strop attached to the lifting handle and to the dinghy hull to prevent centre board ejection from the centre board case when the hull is inverted. One adequate bailer shall be carried on board and attached to the hull with a light lanyard of length which permits the bailer to be operated without releasing the lanyard. For example, an open ended container with a handgrip would be deemed to comply with this requirement. 62 Paddle A minimum of one useable paddle shall be carried on board. 63 Rudder 64 Tiller A rudder pin or pintle of the rudder shall be drilled and fitted with a stainless steel retaining pin. Tiller and rudder stock shall be drilled and fitted with a stainless steel retaining pin. 65 Buoyancy A water-tight bulkhead is permissible as forward and aft buoyancy. The upper surface of the bulkhead or buoyancy material must be at least (1 ½ ) one and one half inches lower than the gunwale line. Polystyrene or similar material shall be completely covered and be secured in the dinghy hull by all-round straps or other equally secure fastenings, so the hull will be buoyant when swamped, as follows a capsize. When swamped, all buoyancy must remain closely positioned to the hull inner surfaces and must not be able to float clear from these surfaces. Buoyancy shall be equally distributed on each side of hull so that dinghy floats on an even keel when swamped following righting after a capsize. Sufficient buoyancy shall be fitted to enable dinghy to float with the centre thwart just submerged when dinghy is carrying all sailing equipment plus a mass of at least 75kg for crew (minimum of 25kg mass per crew member as per AYF Safety Regulations).

12 The minimum volume of buoyancy to be fitted is specified in table below. 12 Hull Construction Minimum Volume of Buoyancy Buoyancy Location Timber Forward 5500 cu.ins (0.09cu.m.) Forward of after edge of centre thwart Aft 5500 cu.ins (0.09cu.m.) Rearward of forward edge of after thwart Total cu.ins (0.18cu.m.) Fibreglass Forward 6100 cu.ins (0.1cu.m.) As above Aft 6100 cu.ins (0.1cu.m.) As above Total cu.ins (0.2cu.m.) 66 SAFETY RECOMMENDATION Towing Line This recommendation is advisory and not mandatory. It is the responsibility of individual Yacht Clubs to decide whether a Cadet dinghy carries a towing line in accordance with A.Y.F. Recommendations. A towing line of suitable strength and floating capability with a minimum length of 25 feet be secured and stowed in an accessible location in the bow section of the dinghy, ready for attaching to the towing ring when required.

13 13 ADDENDUM TO PLANS, SPECIFICATIONS AND RULES OF ONE-DESIGN 12FT CADET DINGHIES RELATING TO TIMBER FINISHING OF FIBREGLASS CADET DINGHY HULLS Table of limitations and tolerances and dimensions of timber finishing of fibreglass 12ft. Cadet Dinghies are to accord with current Plans, Specifications and Rules of One-Design 12ft. Cadet Dinghies with the following exceptions: Paragraph 12 Sliver Strake A sliver strake is to be fitted from stem to stern in one piece seven-sixteenth of an inch (11.1mm) in thickness, minimum width being one and one half inch (38.1mm). Paragraphs 13 and 14 Timbers Timbers will not be fitted. Paragraph 15 Rising Stringer may not be full length but used only as thwart rests. Paragraphs 16, 17, 30 and 31 Centre Board Case and Mast Step The Centre Board Case and Mast Step are to be moulded into fibreglass hull as per Specifications for mouldings of hull. Paragraph 20 Gunwale The gunwale will be built up of glued laminations on a jig constructed to the half breadth dimensions on the Cadet Dinghy plan at sheer line. The gunwale is to be sided one and threequarters of an inch (44.5mm) and moulded one and a quarter inch (31.7mm) and to be fastened through fibreglass hull, sliver strake and each thwart knee. Paragraph 21 The gunwale may be hollowed on the underside from the radius. Paragraph 22 The outer moulding is to be not less than one inch (25.4mm) diameter rounding and is to be faired back to the full thickness one and one quarter inches (31.7mm) at the fibreglass hull. NOTE When fitting gunwale and thwarts to fibreglass hull, to prevent twisting of hull, centre lines stem and transom should be plumbed and hull is to be level. Temporary spreaders are to be placed at Stations 1,3 and 5 to maintain half breadth measurements at sheer line (as per Cadet Dinghy Plan) from centre line of fibreglass hull. Paragraphs 25 to 29 Bilge Stringers 13

14 Bilge Stringers, Floor Boards, Bailing Strips and Chafing Strips are optional. 14 Paragraph 43 (c) 2 The height of the centre line of the sheave of the mast above the upper surface of the fibreglass garboard plank must not exceed eleven feet eleven and one quarter inches (3639mm). To facilitate the interchange of damaged gear it is mandatory that: Mast Step Fitting and distance between Rudder Pintles be standard as shown on Details of Fittings Plan and Sail Plan. FOR AND ON BEHALF OF THE TRUSTEES S. HICKFORD GENERAL MANAGER ROYAL BRIGHTON YACHT CLUB INCORPORATED