Shipbuilding Terms and Phrases “O” “P” and “Q”

The following definitions are from United States Shipping Board Emergency Fleet Corporation publication The Building of a Wooden Ship by Charles G. Davis (1918), a long out-of-print book. They will be very handy when reading the works of such authors as Davis, Howard I. Chapelle, V.R. Grimwood, and others I will reference in this blog. In some cases, I have added further clarification to a definition in the form of editor’s notes. These are in italic, contained in parentheses, and attribute the modern author of the clarification.

O

OAKUM: tarred strands of old hemp, manila or jute rope or other soft vegetable fiber finely combed out and spun into loose strands, used in calking a seam. 

OFFSET: the horizontal distance measured at right angles from the center line of a vessel to points on the side framing at each frame intersection and at predetermined perpendicular heights. The naval architect always furnishes with the sheer, body and molded plans a table of offsets, and this enables the loftsman to correctly check his layout on the mold-loft floor. 

ON BOARD: in or on a vessel; on the upper deck in open air. 

ORLOP: a deck below the berth deck on warships on which cables are coiled, probably now obsolete. Sometimes used as a term for the lowest deck. 

OUTBOARD: a term applied to indicate away from the center line of a vessel; towards the sides of a vessel. 

OUTHAUL: the rope that hauls out the clue to a point of the boom of the fore-and-aft sail, which is furled against the mast. 

OUT OF WIND: a term indicating a twisted surface; out of line. 

OUTRIGGER: a spar or iron forging, which projects from the crosstrees of lofty rigged vessels. The purpose of outriggers and cross trees is to give spread to the backstays and support them in their middle section, also prevent excessive vibration of the rigging from the wind. 

OUTSIDE MACHINIST: a man who erects machinery and equipment on a vessel, and after- ward assists in the operation of the machinery on a test or trial trip. 

OVERBOARD: a term indicating outside; over the side of a vessel into the water. 

OVERBOARD DISCHARGE: the pipefittings and holes through the side of a ship or vessel through which the sanitary, condensing, bilge or fresh water passes or water pumped from the vessel overboard. 

OVERHANG: the portion of a vessel’s hull overhanging and unsupported by the water, at the stern abaft the rudder-post or under the counter. 

OVERHAUL: to separate the pulley blocks of a tackle by hauling one tackle-block away from the other. 

OVER-LAUNCH: ^to run the butt of one plank in a strake one or more frames beyond the butt of the adjoining plank in the next strake. This prevents the butts coming in the same plane and developing a weakness at that point of a vessel. 

OVER-SPARRED: a vessel which has heavier masts, yards or booms than are believed to be necessary, is said to be over-sparred. 

P
PACKING PIECE: thin piece of wood fitted between two timbers, to fill up a deficiency. 

PALLETING: a light platform or grating built above the bottom of the magazine or storage apartment for ammunition, to give ventilation and keep the ammunition from absorbing moisture. 

PAWLS: stout pieces of iron or steel, pivoted at one end, so that they drop into position of their own weight. They are attached to the base of the capstan or windlass in order to prevent it from revolving, except in one direction. Thus, with this device, when an exceedingly heavy strain comes upon the hawser or line being wound in, the pawl at the bottom or side of the windlass, revolving from or with capstan, engages the teeth of the ratchet, on the fixed base or foundation, and effectively prevents the revolution of the drum, except in one direction. 

PARCELING (PARCELLING, PARSLING): the long strips of canvas sometimes wound spirally around a rope so as to give a smooth surface; the process of wrapping or winding a rope with parceling; tarred strips of canvas. 

PARTNERS: the pieces of timber let in between two deck beams to form a framing for the support of anything which is carried on or passes through the vessel’s deck, such as capstans, winches, pumps or masts. 

PATTERN: see Mold. 

PAY (PAY A SEAM): To lay on a coat of tar or cement with a mop or brush in order to preserve the wood and keep out the moisture. When one or more pieces of timber are scarphed, joined or tenoned together, the inside of the scarfs or any surface of the wood coming in contact with another surface, particularly the ingrain, are payed with tar, creosote or other preservative or antiseptic preparation. Seams between planking or deck are also payed with tar, cement or some other preservative after they are calked. Pitch is generally used in this case, as it more effectively excludes the water. 

PAY OUT (PAYING OUT): to slack away on a rope, chain or cable. 

PEAVIE (PEAVY, PEEVY, PEEVIE): a lumberman’s cant hook, having a strong metal spike at the socket end of the staff. 

PILLAR: a vertical member, stanchion or column, giving support to a deck. 

PINK: a vessel with a narrow, round stern, hence all vessels, however small, having their sterns narrowed in this manner, are said to be pink-sterned. 

PINTLES: a metal pin secured to the forward side of the rudder by a strap. The pintle is fitted into a gudgeon, which is secured to the rudder-post. The pintle and gudgeon together form the hinge on which the rudder swings. 

PIPE-FITTER: an artisan who installs iron, steel, brass, galvanized pipes or steel tubing, for high and low pressure steam, hot and cold water supply systems, air, oil and refrigerating systems. He is the man who would connect a great deal of the pipe work in and around the main engine, boilers and auxiliaries. 

PITCH: pine tar boiled until it forms a highly viscous, elastic substance. Pitch when heated and payed on will effectively exclude the water from the face or ends of timbers. It is generally used for paying a seam between planks after calking. Pine tar pitch is the residue from the distillation of turpentine. 

PITCH OF THE PROPELLER: the motion of a vessel when she plunges her head or bow and her stem alternately into the sea, when the waves are very high and the sea rough. 

PLANKING: the timber covering on the outside of the vessel’s frame; the process of putting on the planks or covering the exterior surface of the frames with planks beveled and felled accurately in place. It is referred to as “sheathing a vessel.” 

PLANK-SHEER: the gunwale; the planking laid horizontally along the sides of the timber heads for the purpose of covering, and securing the top ends of the futtocks or bulwarks, sometimes called “covering boards.” 

PLANK STRAKE: a continuous breadth of planking from stem to stem, always laid on the outside of the frame. 

PLATFORM: a partial deck. 

PLIMSOLL: mark painted on the outside of an English vessel, amidship, on both sides, showing how deeply she can be legally loaded. So called from Samuel Plimsoll, who secured the passage of the Merchants’ Shipping Act by the English Parliament in 1876.

The marks are painted in white, and are generally as follows: A circle with a bar across the middle. Following this is a vertical bar with four horizontal bars on the fore side, and one horizontal bar on the after side, the after horizontal bar being the highest.

These five marks are known as follows: 

  • The after highest bar being known as fresh water load-line, sometimes marked “F. W.,” the depth a vessel can load in fresh water.
  • The highest mark on the forward side of the bar is known as Indian Summer, sometimes marked “I. S.” This is the highest load-water line for Vessel’s crossing the Indian Ocean in summer time.
  • The next horizontal bar below is the summer load-water line, and this is for vessels sailing in any location except the Indian Ocean, and which will be known to arrive or depart within the summer season. This line is sometimes marked “S.” 
  • The next mark below this is the winter load-water line, sometimes marked “W.” This is for vessels sailing in any location which are expected to depart or arrive in the winter season.
  • The lowest mark of all is known as the “Winter North Atlantic.” This is for vessels crossing or sailing on the North Atlantic during the winter season. This is sometimes known as “W.N.A.” inasmuch as the North Atlantic is known to be the rougest sea, except around Cape Horn and the Cape of Good Hope, it is considered desirable for the vessel to have the greatest freeboard. 

PLUG: the rounded part of the rudder-stock. 

PLUMBER (MARINE): a man who runs and fits lead piping and fixtures, installs bath- tubs, closets, urinals, showers, lavatories and sinks. He should also be able to use sheet lead in lining tanks, refrigerators, galley dressers, line pipe with lead tubing and cast the lead base for closets from a wooden pattern, rammed and molded in the sand. 

POINTER: a wooden reinforcing timber laid and fastened diagonally across the ceiling near the bow and stem of a vessel. Pointers are generally carried from the stem aft and the stern forward until they reach the full body of the vessel. Their purpose is to help stiffen and strengthen this part of the vessel. 

POOP: the raised after portion of the vessel above the upper or quarter deck. 

POPPETS: timber blocking at the extreme forward and after end of the cradle, which supports the hull of a vessel at these points during the launching operations. The poppets must be very carefully fitted to the exact shape of the hull at the points where they bear, and must be securely fastened together across the ship to prevent spreading while the vessel is in motion down the ways. The forward poppets in end launching, or the poppets near the bow, take the weight of the forward end of the ship at the time the after end commences to float or takes its buoyancy. In large vessels this weight runs up to several hundreds of tons at this period of launching. 

PORT: the left-hand side of a vessel when looking from aft forward; an opening in the ship’s side or deck house. 

PORT-HOLE: a circular or rectangular hole in the ship’s side or house fitted with a metal, water-tight frame and cover. 

PORT-LID: the lid or cover of a port-hole. 

PORT-LIGHT: a heavy glass plate on a hinged frame, fitted to a port-hole. 

PORTS: ports are square or rectangular openings in the bulwarks or top sides of a vessel and serve various purposes, such as ballast ports, for stowing ballast, bow-ports, stem-ports and lumber ports to allow cargo or material to be passed in or out from the deck or hold of a vessel; freeing ports along the bulwarks to allow the water on the deck to run freely over the sides; coaling ports, on the sides of a vessel through which the coal passes on the deck or into the bunkers. 

PORT TACK: when a sailing vessel is under way and her boom and spars are on the starboard side and the wind is coming from the port side, the vessel is said to be on the port tack. 

POWDER-HORN: a term indicating a compound curve. 

PROFILE OR SHEER: a plan showing the longitudinal elevation of a ship’s lines, generally drawn with the stem placed to the right-hand. This plan should show the sheer of the rail, knuckle, decks, the position of the frame stations or sections and the level or waterlines. It should also indicate the form of the ship at the center line and at the fixed longitudinal vertical planes, parallel to the center, called the bow and futtock lines. 

PROPELLER: a revolving device in the water under the stern driven by and attached to the after end of the shaft (called the tail-shaft), which is in turn driven by the engine. By its rotary motion, this device forces the vessel through the water. A propeller consists of two or more plates, blades or paddles set at an angle to the center line of the shaft and twisted with a very sharp pitch like a screw thread. This device, when revolved, cuts through the water, and due to the reaction of the water on the surface of the blades forces the vessel forward or astern, as the case may be, according to the direction of rotation of the shaft. 

PROPELLER-POST: the stern-post of a vessel or post to which the propeller or tail-shaft outboard bearing is bolted. 

PROTECTIVE DECK: the deck in a warship protecting the magazine, engine, fire-room and machinery compartments. This is generally oval or almost flat and built of armor plate. The openings or hatches on this deck are protected with a heavy armored grating. 

PUDDING-BOOM: a boom lashed in a horizontal fore-and-aft position between two boat davits. When boats are swung outboard at sea ready for lowering, they are lashed tightly against this boom, so they will not swing and be smashed when the vessel rolls in a sea way. 

PUMP: a mechanical device fitted on the deck or in the engine or fire-room space, the purpose of which is to remove the water out of the hold or tanks and discharge to any desired point. A pump can pump water from the hold overboard, it may be used to pump water from overboard through the ship’s sanitary system and then overboard, or it may be used to pump fresh water from the fresh water tanks to the cook’s galley, boilers, etc. 

PUMP-CISTERN (WELL)-: the cistern or well into which the water drains. The suction pipes lead from these cisterns to the suction chambers of the pump. 

PUMP-DALES: pipes or drains fitted to discharge the water from a pump over the ship’s side, sometimes called the “overboard discharge.” 

PUMP-MANIFOLD: a series of suction and discharge pipes connected together on the side of a pump in such a manner that the pump can take its suction from any valve or pipe and discharge to any valve or pipe at the will of the operator. 

PUNCH: a mechanical device or machine for punching holes in iron or steel plates, bars, angles or shapes. 

QUADRANT: a fitting on the rudder-head, being, as its name signifies, one-fourth of a circle, and on which the steering chains or tiller-ropes are attached. This device replaces a tiller on large vessels. 

QUARTER (QUARTERS): that part of the vessel’s side near and under the stern; the living accommodations or rooms on board a ship. 

QUARTER-BADGE: the decorative scroll work on the side of a vessel at the forward end of the quarters, near the stern. 

QUARTER-DECK: that portion of the weather deck next to the stern. In the Ferris ship it would be the after part of the upper deck. 

QUARTER-LIFTS: the double topping-lifts that lead from the iron band near the outer or top end of a boom up to and through single blocks, secured to the mast, under the eyes of the shrouds at the head of the lower mast, thence down to the deck. To the lower end is attached a purchase tackle. Flexible wire rope can be used from the boom end up to the masthead, and down to the purchase tackle.

QUICKEN: to give anything a greater curve; “to quicken the sheer,” to shorten the radius by which the curve is struck. This term, therefore, is the opposite of “straightening the sheer.” 

QUICK- WORK: that part of a ship which is above the chain wales and decks, and is so called in shipbuilding because it can be rapidly constructed.