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Yachts - Construction Of The Body Of The Yacht

( Originally Published 1911 )

THE racing surface or the outer skin of a yacht depends largely on the material, workmanship, and designed type of construction.

If the yacht has an excellently planked body, thoroughly smoothed off, sand-papered, and rubbed to a high polish, and the internal construction is not sufficiently well designed to take the twisting strains, thrust of the mast, etc., then the best surface that can be prepared on the railway cannot hold its smooth form, because the yacht in twisting and pounding squeezes the putty and corking from the seams, and long lines of rough ridges appear on the surface. This makes it necessary to haul out again, which is a nuisance and an added expense.

In double-planked boats, of course, this trouble is eliminated. The cost of building, however, is necessarily greater, but it is not every builder who can double-plank a thin skinned boat successfully; keeping the outer skin perfectly tight so that practically no moisture can get in between the skins and so warp and swell them that the surface be-comes humpy and the planks split. It is necessary to have the stock for double planking thoroughly dried and put together in the most painstaking manner.

For the above reasons, it is usually prefer-able to build the racer single skinned, and to build her early in the year, so that she may have a chance to settle into shape as the units in her construction become settled, also that the putty may harden, thereby having much less tendency to be squeezed out after launching. This will give the advantage, in at least the earlier spring races, over the yacht that was hurriedly built at the last minute and put overboard. This one will not show the surface, and is much more apt to twist and pull out of shape, feeling to a person on board actually limber as compared with planking of the other, which is hard and firm.

Another nice way of constructing the light skimming dish racer is the plan adopted by the Canadians for the last ten years in their Seawanhaka Cup boats. This is to use some hard wood, such as Spanish cedar or mahogany, flush seamed and fastened to the frames with small brass nails or tacks, clinched over on the inside of the frame, and with the head, which is small, left flush on the outer surface. This construction is, perhaps, more liable to leakage, but it is a splendid foundation for an exceptionally high-polished surface.

If, when a yacht is hauled out on the railway for cleaning and a surface, she is not allowed to thoroughly dry out, and the planking remains damp and punky, the surface can never show or take a high polish, on account of the soggy foundation. Air the boat out, if the weather is good, as a thorough drying never seems to hurt the little racer, and will always help materially toward a good racing surface.



(This general form may also be used for almost any small class of racing or cruising-yacht.)

Specifications No. 00

In General

In carrying out these specifications, it is understood that all workmanship and materials shall be of the best procurable of their kind, in every respect; that the stock shall be clear, well seasoned, and free from all defects; and that the boat shall be built, fitted, and furnished with everything necessary and customary in a boat of this type, whether specially mentioned in these specifications or not.

The specifications and drawings are intended to cooperate, so that any works exhibited in the drawings and not mentioned in the specifications, or vice versa, are to be executed the same as if they were mentioned in the specifications, and set forth in the drawings, to the true meaning and intention of the specifications and drawings, without any extra charge whatsoever. No change to be made from the plans or specifications by the builder, except upon written instructions from the architect.


Length over all Beam

Length on L. W. L Draft

Moulds and Ribbands

Moulds, made accurately to fit the design, to be spaced every two feet, six inches, accurately lined up and braced to keep them in their positions. Ribbands to be of hard pine at least 1 1/2" X 1 1/2", secured to the moulds and closely spaced. The keel to be thoroughly stayed to prevent it from being moved during construction. Moulds to be left in the boat until she is sufficiently built to insure her holding her shape.

Ballast and Keel Bolts

Ballast to be . . . lbs. of lead in a solid smooth casting, which is to be weighed and a record kept of all trimmings. Lead to be bolted to keel with two 1" and two 1" diameter bronze bolts, headed, or with nuts screwed on the lower ends, and set up with nuts and washers through oak floors and keel, as shown on plan.


Keel of oak sided the same as the rabbet for entire length, and moulded 4" abreast of fin. Keel to be steamed and bent to shape shown on plans, and thoroughly held to that shape.


Upper part of deadwood to be of Georgia pine, lower part of Georgia pine, as indicated on plan. Edges of deadwood and keel to be thoroughly painted before bolting together.


Hackmatack natural crook, sided 3/4" and moulded as shown ; to be fastened to keel with three 1" diameter bronze bolts set up with nuts and washers.


Mahogany 3/4" thick, fitted with suitable cleats on forward side, to take ends of planking. Stern-board to be steamed and bent to the required shape and secured there.


Selected white oak 3/4" X 3/4" steamed and bent to shape. All frames to be spaced 6" on centers. Fourteen frames abreast of mast to be 1 1/8" x 1 1/8 as shown on plan. Seventeen frames abreast of fin to be butted on keel, as shown in midsection. All other frames to be in single lengths from gunnel to gunnel, except three pairs in bow and three pairs in stem, which shall be single moulded from hackmatack natural crooks.


White cedar of as light weight as possible. All planking except garboards where shown, to be 1" finished. Garboards of Georgia pine 1" thick amidships. Planking to be in as long lengths as is possible and have the best of stock. Butts to be well shifted. All planks to be rounded or hollowed wherever necessary, to accurately fit shape of moulds.


All main floors to be of oak, others of spruce, except one in extreme bow which is to be of hackmatack. Two floors through which 1" keel bolts set up, to be sided 2 1/2" in the middle, and moulded and tapered as shown on plan. One floor for-ward and one floor aft of these to be sided 2", otherwise the same. One floor forward and one floor aft of these last-mentioned floors to be sided 1 1/2" throughout, and moulded to conform with the others. One floor at each end of the L. W. L. to be sided 1 1/2" and moulded 2" in the middle, and tapered to ends. One deep floor at mast, as shown in section, sided 1". All other floors to be sided 1", and moulded 1" in the middle, and tapered to ends. Floors to extend between bilge stringers except where shown differently. Four large floors abreast of fin, and one at each end of the L. W. L. to be tied to the bilge stringers with brass knees screwed to both floors and stringers.

Clamps and Bilge Stringers

Clamps of Georgia pine in single lengths, 1 1/2" X 2" in the middle, tapered to 1" X 1 1/2" at ends. Bilge stringers of spruce 3/4" X 3 1/2" amidships, and tapered as shown on plan. Stringers to be set on edge at angle shown in midsection, and lapped by each other amidships as shown. Stringers to be connected with deck beams by pine struts where shown. White pine truss on bilges for about 25' amidships, as shown on plans.

Deck Beams

Two partner beams and beam at each end of L. W. L. to be of oak 1 1/2 X 1 1/2". Beam at jib stay, beams at each end of cockpit, and traveler beams to be of oak 1 1/4" X 1 /14". All other beams to be of spruce 3/4" X 1 3/8". All beams to be notched over clamps as shown. All beams to be spaced 9" on centers except where otherwise indicated. The center line of the deck is to. be straight from stem to sternboard, and beams crowned to con-form to this.


Deck of 5/8" white pine, tongued and grooved, covering boards of mahogany 2" wide. Deck to be painted except covering boards, which are to be finished bright.

Bracing forward

Backbone forward composed of two 3/4" spruce boards shaped as shown, lapped by each other abreast of mast and securely bolted and screwed together, as shown. These boards to rest on frames and be notched carefully over floors. Fastenings to be 2 1/2" brass screws from outside through keel, just clear of every other frame. Backbone to be braced by a pair of 1" hackmatack knees where shown, and by vertical spruce struts between keel and deck where indicated. Two 1 1/4" x 1 1/4" light weight galvanized steel angles connecting deck and backbone where shown. Two 3/8" diam. galv. steel tie rods connecting partner beams and backbone. At forward end of L. W. L. a 1/2" diam, galv. steel bolt to connect large floor with deck beam. Bolt to set up on deck with a nut and large washer.

Bracing Aft

Backbone of spruce 3/4" thick, shaped as shown ; to be fastened in the same manner as the forward backbone. One 1 1/4" X 1 1/4" light weight galv. steel angle connecting deck and backbone. Tie rod and strut at after end of L. W. L. the same as that at forward end. One 1/4" diam. galv. iron tie rod connecting traveler beam and backbone, also one 1/4" diam. rod connecting after traveler beam and transom knee.


Cockpit to be open. Coaming of 3/8" oak. Floor of 5/8" white pine slats 3" wide, laid directly on floor timbers with a 1/4" interval, and made removable. Slat seats of 5/8" mahogany, as shown, made removable.


Two pairs of lodging knees of 1 1/4" hackmatack abreast of mast. One pair of 1 1/4" hackmatack hanging knees on after partner beam. One pair of 1" hackmatack knees bracing backbone for-ward of mast. Three 1" knees on sternboard.

Mast Partners

Mast partners of 1f" spruce thoroughly rodded with 1/4" galv. iron.

Chain Plates

Two chain plates of Tobin bronze 1 1/4" X 3/16" extending 4" beyond bilge stringers, as shown on plan.

Chain plates to be through fastened to planking and keel with 1/4" bronze bolts.

Rudder and Tiller

Rudder blade of oak next to the stock, and yellow pine on the outer edge; to be thoroughly rodded together with composition. Stock of seamless brass pipe 1k" outside diameter. Trunk of seamless brass pipe 1 9/16" inside diameter. Oak tiller three feet long with ball cut on end, to be fitted to rudder stock with bronze jaws, cap, and bolt. Tiller to be so arranged that it may be lifted upright, but not fall below the position shown on plan.

Metal Work and Fastening

All metal work to be of the best bronze, unless otherwise specified. All iron work to be care-fully wrought and galvanized. Galvanized iron fastenings to be used for deck, cockpit floor, and clamps. Plank fastening to be copper, burred over washers ; heads countersunk and bunged. Brass screws to be used where it is impossible to rivet. Floors to be fastened to keel with 1/4" galvanized spikes driven in angling and to the frames with copper.

Painting and Varnishing

Hull to be calked with cotton and carefully smoothed, given priming coat of filler above and red lead below water-line, seams filled with putty to match color of wood, and varnished or painted two coats above the water-line, and painted two coats of green enamel copper or some approved anti-fouling paint below. Name, I" stripe and scrolls to be cut in and gilded with gold leaf. Deck to be primed and painted two coats of approved color. Cockpit, coaming, tiller, etc., to be varnished three coats. Inside of boat to be painted two coats of approved color.

Sails, Spars, and Rigging

Sails to be supplied by owner, but bent by builder.

Blocks as per special list.

Spars to be all solid, of the lightest weight spruce, clear and sound. Wire rigging of plow steel wire rope.

Shrouds 3/4" e.
Boom bridle 5/8 c. flexible.
Jib stay 3/4 c.
Peak and Throat halliards 5/8" c. flexible.
Preventers 5/8 c.
Pennants 5/8 c.
Jib halliard 5/8 c. flexible.
Gaff bridle 5/8 c. flexible.
Balloon jib halliard 5/8 e. flexible.

Manila rigging of best four-strand rope.

Main sheet 15 Runners 9
Main sheet purchase 9 Halliard purchases . . 9
Jib sheets 12 Topping lifts of 1/4 d. cotton.
Spinnaker halliard 12

Bronze turnbuckles (latest pattern) for shrouds 7/16.

Bronze cleats. Halliard cleats 5"; mooring cleat 8"; main sheet cleat 7"; jamb cleats for jib sheets and runners.

One 9" and one 6" bronze traveler.

Spreaders of galv. steel tube to band on mast.


One 25 lb. galvanized iron folding anchor; 30 fathoms of 1 1/8" manila rope; paper bucket; double acting brass pump with hose, large size; one ring buoy with name of boat painted thereon. Boom crutches of hard pine.

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