Wooden ships have been constructed for thousands of years. Around the world, many different construction techniques have been used, some of them quite extraordinary. The ancient Greeks stitched the planks of their warships together edgewise to form an extremely light frameless load-bearing shell, much like a modern airplane fuselage. However, most wooden ships are built using a basic framing system that has changed little over the centuries.
Wooden Ship Framing
The illustration above shows most of the basic components of a wooden ship's frame. The keel is the backbone of the vessel. Attached transversely to the keel at regular intervals are angled assemblies known as "floors". The floors carry the vessel's ribs, shown below. The keelson is mounted atop the floors, sandwiching them into an extremely strong structure. The keelson provides additional strength and stiffness to the keel and floors. Below the keel, most vessels also have a "false keel" ( not shown. ) the false keel is generally not a load-bearing structure. Rather, its purpose is to protect the keel from wood-boring organisms and accidental groundings, and also to provide lateral resistance in the water so the ship will track straight in a crosswind.
The bow of a wooden vessel is built up around the curved stem, while the stern is built up around the sternpost. Assemblies that were either too large or too oddly-shaped to be cut from a single piece of wood were built up using scarf joints - diagonal joints that spread stresses across a larger area than a simple butt joint. A scarf joint is apparent as the diagonal line in the keel above, and also in the assembly detail of the "floors." Especially high-stress areas, such as the bow and stern, are reinforced with large wooden "knees" and other reinforcing pieces ( not shown. ) the keelson also carried the lower ends of the masts in sailing vessels.
Floors protruding from under the keelson, on the "Middle Barge."
Below is a drawing of a typical wooden ship side and deck construction. The ribs are carried at their bases by the "floors". The outer surface of the vessel is sheathed with heavy wooden planking and waterproofed with caulk, a mixture of tar and hemp called "oakum". The inner surface of the vessel is covered with thinner planking known as "ceiling." A large longitudinal timber running around the inside of the hull called the "shelf" carries the transverse deck beams, which are supported along the centerline by stringers and stanchions extending upward from the keelson. Critical joints are reinforced with "hanging" knees, and the fasteners used are of similar materials to those described above, but smaller. Framing elements were usually of oak, while planking was more commonly pine.
Wooden ship ribs, planking, and decking.
Three curved wooden ribs with some outer hull planking still attached,
protruding from the sand on the "Middle Barge."
Large ( 3-4 foot ) copper drift pins exposed by separating timbers on the Delaware.
Fasteners like this were used to assemble large parts, like the keel.
On older vessels, wooden pins known as "treenails" were used instead of metal fasteners. This avoided galvanic corrosion of the fasteners. Corrosion of metal parts was a problem even in wood hulls. In a salt environment, different metals could react with both the wood and each other.
Typical wooden ship's "skeleton"
See builder's specifications below.
Construction begins at the overhanging stern.
Ribs curve up from the keel near the stern. The rudder is visible at right.
The stern again, from above. It's not hard to see why this part of a wreck lasts the longest - the timbers are close-set and massive.
Schooner barges were built for maximum carrying capacity. A real sailing ship would have finer lines than the boxy hull that is taking shape here, but would otherwise be similar. Note the two workers for scale.
Nearing completion, with deckhouse, but still unskinned.
Not yet rigged, but ready for launch. The towing bit in the stern appears to be wooden. Note workmen on aft hatch cover for scale.
The structure of a wooden hull is shown to good effect in these images of a
schooner barge after a collision. Notice that the interior decks have been removed
to facilitate loading of bulk cargoes from above. Fasteners, planking, ribs, ceiling,
keelson, beams, stanchions, decks, hatches, and a mast are all plainly evident.
The fasteners used to attach all these various parts and joints have changed over time, from wooden pins called tree-nails initially, to iron bolts, and finally to copper pins. The largest pieces are secured with extremely large fasteners known as drift pins, up to several feet long, which were hammered into pre-drilled holes. Most of the wooden shipwrecks you will encounter while scuba diving are of an age where they will have metal fasteners.
Large ( 3 - 4 foot ) copper drift pins exposed by separating timbers on the Delaware.
Later wooden hulls were sheathed in copper sheeting, or covered with large-headed copper sheathing nails, to deter wood-boring marine organisms that would destroy the vessel. Not only sailing ships, but also early wooden steamships were built along these lines, the only modification necessary being to accommodate the propeller in vessels so-equipped. The Delaware is a classic example. Modern wooden sailing yachts are still built using this same basic design.
A rather well-preserved wooden wreck - the "Cadet" - probably a schooner barge.
Notice how the interior of the wreck is filled with sand, and the keel is deeply buried.
After a wooden ship sinks, the hull begins to deteriorate. First, the masts are knocked down by the government, lest other ships collide with them. You hardly ever see a mast on a wooden shipwreck - they are either salvaged, or simply float away. Light structures such as deck houses and hatch covers are quickly demolished by weather or float away, until only the sturdy hull remains, weighed down by ballast and cargo.
Over time, the weight causes the hull to sink down into the mud, and it fills with sediment. Eventually, the ribs weaken, and the sides are knocked down by storms. Waterlogged but not heavily ballasted, these usually lie like angel wings only slightly buried next to the main wreck, which eventually may sink so deep that only the lines of protruding stumps of broken ribs and planking mark the outline of the vessel. The bow and stern collapse, until finally the wreckage is flattened into a debris field.
Sometimes storms or currents scour out the insides of an old wooden wreck, and you can see the remaining structure, ballast stones, etc. Wrecks like this provide innumerable hiding places for marine life. Lobsters and fish will shelter in the gaps between the keel and keelson, as well as between the ribs and planking, and under the ballast stones. Lobsters will also dig their own holes under any overhanging pieces.
Small vessels are still framed-up with wood today
Below are builder's proposed contractual specifications for a 3000 ton four-masted schooner barge, typical of turn-of-the-century wooden hull construction, from the Palmer Shipyard in Noank, Connecticut, which closed in 1915. The actual blueprint plans mentioned in the text were apparently lost in a fire at the shipyard. The "P. & R." company mentioned is the Philadelphia and Reading Railroad, which acquired six similar but smaller barges between 1901 and 1914, upon which this design is based. Six barges were built approximately to this design for the P&R between 1901 and 1914.
As much as possible, I have attempted to preserve the original type-written look and feel of the document, along with the old-time wording and most of the typos and spelling mistakes where they did not affect readability. Of particular note are the massive size of some of the timbers, as much as 16" x 16" solid oak ( see photos above. ) This sort of construction would be prohibitively expensive today, if it is still possible at all ! Also of interest are all the little pieces that go into such a vessel - just about everything is listed, right down to the bell and toilet.
For proposed 3000 ton wooden' sea barges.
Length overall 265 feet
Length on keel 240 feet
Beam to outside of planking 45 feet
Depth of hold from floortop of beam 20 feet
To be white oak sided 14 in. moulded 12 in., to be in long lengths put together with 7 ft. hook scarf, each side to have a plate of 1/2 X 2 in. iron let in flush with two 7/8 countersunk holes, through which clinch bolts are driven and riveted on rings.
To be of white oak sided 16 in., moulded 16 in.
To be of white oak sided 14 in., moulded about 14 in., to have root on lower end.
To be of white oak sided and moulded 14 in., fastened to stem with one inch bolts about 15 in. apart.
To be of yellow pine sided 14 in., moulded to suit cants and ceiling, fastened with 1-1/8 bolts.
To be of yellow pine 14 x 14, six of them in the centre, four in the first tier, two in the second tier.
Intermediate 14 x 14, two on each side between the centre keelsons and the bilge keelsons, all fastened with 1-1/8 iron.
To be of oak, chestnut, hackmatac and yellow pine, moulded 16 in. at the keel, 10 in. at bilge and 7 in. at the plank sheer. The floors and first futtucks sided 8 in., balance of frame 8 in. Frames fastened together with 3/4 in, bolts. Room space 24 in.
Limbers 1 1/2 x 4 cut in frame and garboard, and fitted with limber chain galvanised.
To be of white oak sided 8 in. and according to plans.
the first three streaks next the bilge keelson to be 14 x 14. 0ne streak 13 x 13, the balance to clamp for lower deck beams to be 12 x 12. The clamp to be 14 x 14, one 6 x 14 inch piece put in at the end of the beams. The fastening to be 1 in. headed bolts. The 14 x 14 to have 7 ft. scarf, the balance 6 ft. scarf.
To be of yellow pine of four streaks, two 8 x 12 and two 10 x 12. Deck beams to be dovetai1ed or jogged into shelf.
To be of yellow pine, beams in hatch space 14 x 14 and to be 10 feet in the clear. Forward and aft of the hatch the beams may be 12 x 12 spaced four feet on centres or on every other frame. Beams framed with 6 in. lodging knees. Hanging knees in hatch space to be 9 and 10 inches. Hanging knees forward and aft may be 8 in.
the space between main beams to have short beams sided 3 in. and moulded to space, fastened to the hatch combings with one inch screw bolts and to the shelf pieces.
To have 5 strongbacks in each space, the centre one to be 6 x 8, the ones on the side to be 5 x 6.
BREAST HOOKS and POINTERS
Pointer made of four courses of 3 x 10 yellow pine 36 ft. long, two set forward, one aft, fastened to frames with 7/8 in. bolts, the filling to be yellow pine kneed with two 8 in. hackmatac knees.
STANCHIONS in HOLD
the stanchions to be of oak in two pieces 6 x 10 locked over the lower beams, fastened to keelson by a 1/2 x 3 in. strap on each piece of stanchion, the upper bolted to the upper beam and further secured by a strap to go over the beam and down over the stanchion.
Arranged as on Class "D" Barges.
the plankshear of 5 x 14 yellow pine let down over stanchions and fasten through stanchions and into shear streak and waterway.
Rail of 6 x 14 yellow pine, with two stringers 5 x 10 under the rail let into the stanchions one inch. Stringers fastened through stanchions with galv. bolts. Rail to have 7 ft. scarf and bolted to the two stringers,, Around the stern to have solid chocks for rail to set on. Rail to be about 3 ft. high. From stem aft to hatch the frames carried up to rail and planked inside and out with 3 in. plank.
To have three stationary bulkheads in hold, located as may be wanted securely fastened to floor and beams, fitted with doors as to pass through fore and aft. Also to have temporary or shifting bulkheads to suit inspector.
To be of yellow pine except white oak may be required on account of bending.
the garboard streak to be 9 x 12, the second streak to be 8 x 12, the third streak 7 x 12, the balance of plank to plankshear to be 5 in. thick.
the first and second garboard streaks fastened to frames with 7/8 headed galv. bolts, the first streak edge bolted through keel in every other frame space with one inch bolts.
the 7 x 12 streak to be bolted with 7/8 galv. headed bolts. Some large galv. spikes may be used in working plank to timbers. The balance of planking to be fastened with galv. spikes and locust treenails, say five or six streaks on bilges to be fastened with 7/S galv. bolts; all plank to be square fastened; all butts to have galv. butt bolts.
the hatch coamings to run the whole length of the hatch and cabin and to be of three courses of yellow pine. The two lower ones 12 x 12, the upper 10 x 12, all to be in long lengths and to have six ft. scarfs.
To have an oak piece on top to receive the carlins and covering, to be thoroughly fastened together and to the deck beams with one inch iron.
HEAD LEDGES IN HATCHES
To be of yellow pine, 8 in. thick and raise in the center about 9 in. Hatch space to be 17 or 18 ft. wide or as may be ordered. One 12 x 12 stringer along of the hatch coamings to run fore and aft, the length of the coaming, securely fastened to same and beams with 7/8 bolts.
HATCHES and COVERS
the carlins of oak 2 x 3 1/2 , three to each hatch. The covering to be 1-1/8 spruce matched, with oak pieces at the coamings and at the centre. Hatch cover to be of No. 5 Cotten Duck.
To be of 3 1/2 x 6 yellow pine in long lengths laid with the center line of vessel, to be plugged and fastened to the beams with 6 in. galv. spikes, two spikes in large beams and one in the small ones.
the thick stuff forward of hatch and aft of cabin to be 5 in. thick in one length seven or eight inches wide, thoroughly fastened with two 3/4 galv. headed bolts at each beam, the thick stuff forward to be wide enough for the windlass bed.
To have two 16 x 16 white oak bitts forward and two aft, the lower end securely fastened to the deadwoods or to the lower breast hook, fastened together with a 30 in. cavil. One forward and aft to have a brass cap instead of babbitted metal.
To have six 12 x 12 white oak bitts on each side to extend down through the deck and bolt to the side of vessel, the tops covered with sheet brass. To have five partners in deck for bitts to go through ,,
the rudder stock to be white oak 18 in. diameter, the balance of rudder may be of yellow pine bolted with 1-1/8 bolts. The rudder to have three sets rudder braces with 4 in. pintles to be of composition.
To have four streaks of wearing pieces. The upper one to be 3 x 10 and to extend all around the vessel. The second, third and fourth to be 3 x 9 or 3 x 8 or of such width as not to cover the seams in the outside planking and to extend as far as they can be worked to the vessel.
the outside to have five threads of best oakum, the garboard, second and third streaks to have 6, 7 & 8 threads or the seams to be filled. The deck to have two threads and to be pitched, outside seams to be painted.
the hawse pipes of such size as to allow the chains and shackles to run through freely.
CHOCKS and CLEATS
To have a babbitted towing chock on bow for hawser, two roller chocks on each bow and one on each side aft, cleats located on deck as directed. Two chocks on rail aft for hawser.
RINGS and EYEBOLTS
To be fitted as may be directed.
PUMP' WELLS and PUMPS
To be put in as directed, one forward and one aft. To have two bilge pumps of suitable pattern.
To have a band strap 3/4 in. x 8 in. to run from stem aft to within about 30 ft. of the stern and to be let into the heads of the frames on the outside fastened through frames.
the band strap fastened together on the inside with butt pieces hot riveted.
At intervals of four feet on this band strap, diagonal straps of 1/2 x 4 iron will run down at an angle of 45 degrees to let into and fasten to each frame with two 3/4 in. bolts.
the diagonal straps fastened at each crossing and to the band strap with hot rivets.
the straps to have a coat of red lead and oil.
the cabin built according to plan. The covering and interior work to be the same as on the 1600 ton barges of the Reading Co., to be fitted as to rooms, cupboards, berths, drawers, etc. as directed by the inspector. Dimensions and plan of cabin as per drawings.
the pilot house located on top of cabin and built on the general plan of the 1600 ton barges of this Co. including room for men in after part of house; to have necessary deck irons for stoves; to have galvanised sheet iron to protect from fires; to have galvanised iron railing around top of cabin, with a one iron ladder on each side of cabin; grating on top of cabin house.
Store room to be under deck aft of cabin, with bulkheads and floor, cupboards to be made and placed as directed; access to store room through a hatch 2 1/2 x 2 1/2 feet.
FORECASTLE and TANKS
Forecastle to be built on the same plan as the 1600 ton barges, the size as directed.
the water tanks to be placed forward of bulkhead and made of 1/4 in. iron, to hold not less than 3500 gallons of water, with man and hand holes, partitions to break the force of water when vessel is rolling; two tanks to a barge.
TANK FOR CABIN
Galvanised iron tanks to hold 800 gallons of water, fitted with hand holes and placed as directed; may be two tanks.
Water closet with overhead tank furnished and fitted as directed.
To have a No. 9 Hyde Windlass with two large and long gypsy heads, two wild cats for 2 in. chain. The engine to be placed on bed below deck and to have two cylinders 10 in. by l0 in.
One upright tubular boiler 100 lbs. steam pressure for engines 10 in. x 10. in. manufactured by Hyde Windlass Co., Bath Me.
All necessary piping to be furnished and fitted up in a workman-like manner.
One Duplex bilge pump, of Worthington pattern, 6in. suction, and one Duplex Worthington feed pump for boiler, size 4-1/5 in. x 2 3/4 in, x 4 in. Style of pump same as on P.& R. barges.
ANCHORS and CHAINS
To have two anchors, one of 3000 lbs. and one of 2500 lbs., with 100 fathoms of 1 3/4 in. stud link chain, fitted with joining shackles every 15 fathoms and with proper anchor shackles.
ANCHOR DAVIT and DECK
To have an anchor davit 6 in. diam. on each bow of such shape as to place anchor on rail, davit fitted with blocks and fall.
Another deck built forward to lash anchor on. The deck where anchor rests covered with 1/8 in. galvanised iron.
To have two pair 2 1/2 in. boat davits so placed as to land on skids that run from top of cabin to stanchions that run up from rail.
To have two 16 ft. lap work boats all fitted with oars, rowlocks and canvas covers.
MASTS and SPARS
To have four masts about 80 ft. long; the two forward masts to be 20 in. diam. at the deck, the third to be 19 in. and the fourth to be 18 in. at deck; four booms forty feet long, 10 in. diam. where sheets are fastened to them; three gaffs 20 ft. long.
All iron work furnished for spars and rigging and put in place. All to be rattled down, the forestay 3 1/2 in., springstay 2 1/2 in., top mast stay 2 1/2 in.
All running rigging of ' manila rope, halyards and sheets furnished and fitted complete, size as directed, all necessary fasts, warping, running and deck lines, signal halyards and heaving lines furnished including towing hawser
200 fa. 9"
4O fa. 6"
5O fa. 5"
150 fa. 4 1/2 "
two running lines 45 fa. each 5 1/2 ".
All necessary blocks of proper size to rig and fit vessel complete in every part, the blocks to be of the best quality of patents, except the sheet blocks, blocks to be iron strapped.
To have one capstan placed aft.
SAILS and SAIL COVERS
Sails to be five in number as shown on plans, to be fitted to hoist on the masts with hoops. All sails to be made from No. 2 Cotton Canvas. Sail covers to be fitted and furnished with stops.
the bottom to have two coats of Copper Paint up to 7 1/2 feet. Top sides to have three coats of Metallic Paint. The iron work to be primed with one coat I-oxide paint then covered with two coats of lead paint, the last color as may be wanted.
Cabin and Pilot House three coats lead paint on the outside, the last coat color as directed. The inside painted with two coats of paint and grained.
the name of the vessel to be painted on each bow, the name and hailing port on the stern in six inch letters. The name board on front of Pilot House fastened on with brass screws, the letters on board to be 8".
One brass bell on front of Pilot House and arranged so that it can be worked from the inside of same.
Barges to be sheathed with galvanised iron to protect them from ice. Iron to be in sheets not less than 48" x 36" and of No. 16 B.W.G. Sheathing to commence at stem and run aft on both sides as far as the aft mast. Sheets placed with 48" dimension in vertical direction. All seams and butts which will be covered to be caulked full, well seamed and filled with Portland cement before sheathing as put on.
Stem covered with No. 14 B.G.W. galv. iron bent around stern and extending as far as wood ends. Stem covered from keel to top of stem.
Sheathing to be fastened with 1/4 x 2" galv. nails 2 1/2 " apart on the edges, 3" apart in center of sheet, sheets to lap 2".
IRON on KEELSON
Straps to go over keelson to protect from being cut by diggers and coal to be 1/4 x 4, fastened by 3/8 galv nails.
Boxes fitted for side lights, steering lights*, binnacle light box. etc. as required.
DECK BILGE PUMPS
Two No. 3 Edson or other good design; one placed forward of amidships and one aft and fitted complete."
One steam gypsy located aft as directed, with engine 5" x 7" and to be fastened to floor in after store room, shaft to go through to upper deck with gypsy head 22" diam. of the Hyde Windlass Co.'s pattern or American Windlass Co. pattern, steam supplied from boiler forward with pipes running
under deck to gypsy engine. Pipes to be covered with felt or asbestos covering.
DECK WATER: PIPES
A 3" pipe to run up from engine room and from large bilge pump and to run as far aft as main cabin along side of main hatches on deck and to have one 2 1/2 " hose connection placed every 50 feet apart, connection to have caps of brassy this pipe to be used for washing down and for fire purposes.
One or two as may be desired with capacity of 12 tons coal, to have hatch gratings over same, all to be arranged as directed by Co's Sup't.
Desk and drop table for Captain's room and table for mess room; also gratings for pilot house, shelves and racks for engine room and slat gratings for hawser to furnished and fitted by the builder; barge to be salted in both
Material used in construction to be of best quality, free from defects. Frames to be as nearly as possible of natural crooks and yellow pine of prime inspection.
Halyards, sheets and top lifts to be 3 inch.
Galv. iron wire preventer stays to run from mast to mast and set up with two double blocks 2 3/4 " rope running to deck so that same can be operated from below when necessary for discharging purposes.
Three hauling out falls and blocks to be furnished and rigged up in place; also wire straps with eye in same made fast to booms for hauling out tackle. Storm shutters on side of pilot house and arranged with hinges to drop down. Steering gear chain to be not less than 1/2 ".
Gratings to be made and fitted up on top of cabin.
Pipe railing to extend all around top of cabin.
Vise bench, vise, lockers and drawers, also racks for tools with wrenches, etc., for boiler and engine placed in engine room.
A window to be placed in aft part of pilot house.
Four lamp boxes on top aft part of cabin as designated.
One iron came on aft part of pilot house for stern light.
Slat grating forward on deck for towing hawser.
One water barrel and rack for same and fastened in place.
Ice house aft in main cabin with shelves and made as directed.
Bilge suction pipes to be galvanised and arranged as directed.
Four double blocks with 2 3/4 " falls rigged on tiller of rudder for relieving strain on same when barge is at anchor.
Two deck lights over engine room and located as directed.
Decks to be painted with two coats of pine oil.
Leading sheaves to be placed at the foot of each mast for hoisting sails by windlass power.
Gypsy heads on windlass shaft to be same pattern as now on Class "D " barges of P. & R. Ry. Co. and long enough to suit 9" hawser in lieu of 8"
Starboard and port anchor chains to be shackled together at axis in chain locker.
A desk with drop leaf and drawers; also top for books, papers, etc., to be built in captain's room.
Engine room and store room aft to be white washed with two coats of white wash to within four feet of the floor; up to four feet to be painted with two coats of such color paint as may be approved.
Woodwork around boiler stack to be covered with galv. sheet iron over air space strips.
Brick work all around boiler ash pan and extended out far enough for an ash dump and woodwork in wake of ash dump covered with heavy galv. sheet iron.
Steam pipes 3/8" with stop valves to run into all suction pipes for thawing our pipes running to suction end of bilge pump.
Iron ladder on port and starboard side of main house extending to top of main house.
Wire rope back stays to run from top of mizzen mast to rail and set up with lanyards.
Top of hatch combings in wake of hatches to be covered with galv. sheet iron to prevent coal diggers from damaging same.
Figures for draught of water to be cut in on each side of bow and stern and must be marked accurately and painted in white.
One sounding pipe on deck and one in cabin, located as directed. A stop to be placed at each door of cabin and fastened as directed.
Door sills, etc., covered with light brass.
Two scuttle plates to be placed over coal bunkers and one over engine room and all to have iron gratings.
Exhaust from windlass engine to run into stack and also outside and arranged as directed.
Two deck lights over aft store room.
Ridge pole and wood stanchions fitted up aft with canvas awning.
Main and pilot house to be varnished with two coats of spar varnish, after being painted with such colors as may be selected.
A small scuttle arranged with roller and an iron cover placed on forward deck over engine room and a slat grating on port side of engine room floor to allow towing hawser to be placed in engine room when necessary; all scuttle covers to be securely fastened and water tight.
Water tanks aft to be covered with felt and boxed in and all pipes leading to same. Bottom of tank to have 1- 1/4 gate valve so that tank can be cleaned out. This tank may be of galvanised iron.
Galvanised sheet iron or zinc for back bottom of stoves in mess room, kitchen and pilot house; also deck irons for stove pipes to be furnished and fitted in place by builder. Stove to be furnished by P. & R. Ry. Co.
Floors in Captain's room, mess room, kitchen, seaman's quarters and pilot house to be painted or ,' varnished as required.
Grating in pilot house.
Speaking tube with whistle to run from Captain's room to pilot house.
General details, etc., similar to those on P. & R. Co's sea barges Class "D" Type.
These specifications were obtained from the Noank Historical Society, with
additional information from Mr. Robert Palmer. Courtesy of Mr. Roy Eliassen.