Using a marine surveyor
Types of survey
Terms & Conditions
Survey contract
Booking a survey

. 1-Glossary
. 2-The Safety Culture
. 3-Skin Fittings
. 4-Marine engine development
. 5-Diesel oil in wood
. 6-Timber problems
. 7-Stainless Steel
. 8-Documentation
. 9-Legal Matters
. 10-Galvanic action-Electrolysis
. 11-LPG systems
. 12-Yard storage
Discussion room


1. Glossary

‘A’ brackets or ‘P’ brackets
– some competition yachts and powercraft fitted with spade rudders, do not have a conveniently placed skeg for mounting the outboard gland of a sterntube in which case an ‘A’ or ‘P’ bracket has to be fitted.
– behind or near the stern of the vessel
– the portion of the vessel at half its length
– for general use there are considered to be two categories of anchor - the main or ‘bower’ anchor and the auxiliary or ‘kedge’ anchor. As the name suggests the ‘bower’ anchor is the anchor used on the bow, is heavier and attached to much more cable. A kedge anchor is a smaller, general purpose anchor used for short term anchoring, for assistance having run aground and as an additional anchor in adverse weather. Usually the kedge is fitted with a warp rather than chain so that it is easier to handle in a dinghy for ‘kedging off’ or laying out a second anchor at a mooring. (Types - Fisherman's, Grapnel, Danforth, Delta, Bruce, CQR/Plough). Cable - for effective mooring the anchor relies to a good degree on its chain and if a warp has to be used at least 5 metres of chain should be used between the anchor and the warp.. It is preferable to carry sufficient chain for the for the operational cruising area of the vessel - or 4x length of boat or a min. of 30 metres. End of chain should be lashed or seized to strong point in chain locker (not shackled!)
– device for measuring the strength and direction of the wind (usually at the masthead although there are some hand held devices.
Anode (sacrificial anode/ sacrificial plate)
– a solid block of zinc or magnesium fastened to the outside of the hull below the waterline to reduce the electrolytic corrosion of hull material
– ropes which support the mast against the forward thrust of the sails. They stretch from the masthead back to either side of the vessel or to the channels.
– any solid or liquid weight placed in a ship to increase the draught, to change the trim or to regulate the stability.
– a thin flexible length of wood or hard plastic used for fairing and drawing curved lines. Or used in batten pockets to smooth the shape of a sail.
– one of a number of thick strong timbers stretching across the vessel from side to side, supporting deck and sides and firmly connected to the frames by strong knees. They are generally higher at the middle than the sides to assist water to flow off the decks more easily. The longest beam is the midship beam which is mounted across the widest frame (midship frame).
Beam knee
– heavy right angled timber connecting a beam to the vessels frame.
– mastic used under fittings to prevent leaks.
– a) the area of the hull between the lower part of the side and the outer part of the bottom. b) The space below the cabin sole or engine room plates used as a drainage space.
Bottle screw
– threaded cylinder (the bottle) led into the outer end of a shroud or stay for setting up or tightening standing rigging.
– the forward part of the vessel’s side from a point where the planks curve inward to where they meet at the vessel’s stem.
– a spar used to extend the foot of a sail or any spar heeled out from the vessel’s side.
– vertical sub-division wall within a vessel. May be transverse or longitudinal, watertight or non-watertight bulkheads of no particular structural importance but used simply to sub-divide cabin areas are called screen bulkheads.
– protective structure built around the edge of the upper or weather deck to prevent the crew from falling overboard.
Buttock line
– a fore and aft vertical section of the boat found on the sheer plan of a lines drawing.
– compartment used as living quarters on a ship.
Cable locker
– compartment in the bows of a vessel where the anchor cable is stowed and its inboard end is secured.
– the transverse downward curvature of the upper or weather deck.
– generic for any material covering (sails, awnings, screens etc...)used on a vessel and derived from an era when commercial sails were made from different weights of canvas which is a coarse fabric made from flax.
Carvel built
– vessels built with the planking running fore and aft but built edge to edge not overlapping (as in clinker built boats).
– the internal planking of a vessel.
Chain plates
metal fittings secured to the sides of a vessel from which the shrouds are set up.
– a longitudinal hard corner forming the bilge of fast motor vessels or barge type hulls - double chine - soft chine (curved rather than hard edge).
Chopped strand mat
glass fibre re-reinforcing sheet consisting of fibres randomly arranged, not woven.
Circuit breakers
automatic cut-out system to protect a circuit from overloading in place of a fuse.
– a fitting with two horns around which a rope can be tied.
construction method where planks overlap (lapstrake in America).
the deck or roof covering a cabin that is raised above the deck level to increase the headroom below.
raised sides of a cockpit or hatch
originally the compartment under the lower gundeck in a man’o war where the wounded were attended to by the surgeon during battle. These days it refers to the open area in a small vessel from which it is controlled.
The International Regulations for preventing Collision at Sea. There have been rules covering the navigation of ships at sea for well over 200 years. The first official regulations. were introduced in 1840. Current regulations introduced in 1972 with amendments in 1983. The application of the rules is covered by rule 1. – “the rules apply to all vessels on the high seas and in all waters connected therewith navigable by seagoing vessels” therefore COLREGS. apply to all vessels including yachts and small craft. The REGULATIONS cover Visibility of lights, lights for power driven vessels, towing and pushing, sailing vessels, fishing vessels, vessels not under command or restricted in their ability to manoeuvre, vessels constrained by their draught, anchored vessels and vessels aground, equipment for sound signals.
Cold moulded
construction method where the hull is laminated from several layers of veneers fastened to a jig.
arched section curving upwards and aft from the wing transom and buttock to the bottom of the stern above.
framework (frequently welded metal) which supports a vessel while she is being built or laid up out of the water.
Cutlass bearing
outboard bearing for the prop. shaft is either bronze or a cutlass rubber insert which has a grooved hard rubber bearing bonded to a brass sleeve which is clamped in the outboard gland and requires water for lubrication not grease. Drawback is that it is longer than the normal bronze fitting to provide the equivalent bearing effect and there is often not enough room to fit one.
– horizontal flat or curved surface forming a working area for the hull. The upper deck is usually weather tight and cambered, lower decks will usually be watertight.
– loss of zinc from a copper zinc alloy such as brass, due to immersion in salt water - results in a weak and porous copper residue.
– a raised protective covering abaft the the cabin in a small boat, for the steering position and all round visibility
– round wooden plug used to hide fastening and laid with the grain.
– place in the middle of a vessel’s stern where her name and port of registry are inscribed.
– curved cast or wooden open topped piece secured to the edge of a deck through which mooring lines are run to give them a ‘fair lead’. When cast with a top to form a ring they are called Panama fairleads.
– Strips of wood fitted to the edges of tables and other flat surfaces to prevent objects sliding off.
Fore (forward/forrard)
– in the forward part of the vessel towards the stem.

Fore cabin
– part of a vessel’s accommodation second in importance to the saloon.
– distance from the waterline to the upper surface of the freeboard deck.
– area used for food preparation below decks.
– single broken strand(s) in a stainless steel wire rope. These are dangerous as they can cut through a glove and flesh easily. Time to change the wire. Check for gashers using a soft cloth carefully!
– a specially formulated resin mix applied to the mould before the lay-up of the first layer of reinforcement. this coating duplicates the mould surface, forms the outer cosmetic surface and provides protection against weathering. It is an unreinforced pigmented polyester resin. It is not a coating but rather part of the moulding.
– double concentric metal suspension fitting in which a compass bowl, cooker etc... can be retained in the horizontal position by counteracting the motion of the boat.
– a dangerous fault whereby standing or running rigging does not have a direct line of tension through a shackle or bottle screw thereby putting an uneven load on the shackle and the eye that it is secured to.
– glass reinforced plastic (/FRP)
– a thicker timber than the ordinary side planking fitted at and forming the lower edge of the gun ports in a warship - these days it describes the upper edge of the bulwarks.
Halyard (halliard)
– rope or tackle used to hoist or lower a sail, yard or gaff.
– rectangular opening in the deck providing access.
– the front or fore part of a vessel including the bows on each side.
Head timber
– timber supporting the gratings on the fore part of the vessel.
– the vessel’s lavatory (formerly a grating over the bow or beakhead).
– a vessel is heeled when inclined by an external force.
– specifically the tiller; the lever controlling the rudder. Used in a wider sense to describe the steering gear.
Helm port
– opening in the stern of a vessel housing the rudder stock and allowing it entry into the hull for connection to the helm.
Helm port transom
– timber reinforcement of the helm port.
– the body of a vessel excluding mast, sails and rigging.
Joggled timber
– frame shaped in such a way that each attached strake slopes outward giving the appearance of being clinker built although the planks do not overlap.
Jury rudder
– a temporary rudder rigged if the true rudder has been smashed or carried away.
Jury steering gear
– a temporary steering gear rigged if the vessel’s proper steering gear is inoperable.
– the main longitudinal structural timber or plate forming the backbone upon which the vessel is constructed.
– Internal keel mounted over the floor timbers and immediately above the main keel, providing additional structural strength.
Keel staple
– Iron or copper staple fastening the false keel to the keel.
Lady’s hole
– a small compartment for stores.
– making a curved shape by gluing thin strips of timber against a jig. Each strip is called a laminate
Length overall (LOA)
– maximum length of a vessel.
Lloyd’s rules
– comprehensive construction guidelines drawn up by Lloyd’s.
Locking pintle
– a flanged pintle preventing the rudder from being accidentally unshipped.
– any for and aft member.
– vertical or raked spar stepped on a vessel’s keel and carrying sails, yards, rigging and other gear. A mast can be made of one or more pieces of timber or of tubular steel or alloy. High masts can consist of several masts one above the other.
– the point midway between the forward and aft perpendiculars.
Moisture content
– weight of water contained in timber expressed as % of dry weight. Moisture readings can be particularly relevant when diagnosing osmotic reactions or delamination.
– made as one part. Modern laminate hulls are monocoque structures.
– 1) the height or depth of a member measured normally to the centre line or hull planking
– 2) a fibreglass hull as it is removed from the mould and before any further work is started.
1X19 Stainless Steel
The majority of modern yachts have 1x19 stainless steel standing rigging. This is made up of 19 individual wires which are extruded and given a spiral twist so that each wire lies snuggle in place in a standard pattern.This consists of a central wire surrounded by 6 and an outer ring of 12 wires. This rigging is simple, reliable and should have a working life of 10 years cruising (5 years racing) before it needs to be replaced.
– the male pattern from which a female mould is made prior to producing the finished article from another material. e.g. Fibreglass hulls are laid up in fibreglass moulds which are themselves created from a wooden plug./ metal ballast keels are cast in sand moulds made by ramming the sand around a wooden plug.
Polyester resin
– the resin normally used for producing fibreglass hulls.
– a revolving, screw-like device used to propel a vessel through the water.
– the side of a vessel between midships and the stern.
– a general term for ropes and wires of a vessel including those that support the mast and yards (standing rigging) and those used for working the sails (running rigging).
Rubbing strake
– for and aft member fastened inside the timbers to support thwarts, soles and other transverse members.
– vertically aligned controllable plane surface at the after end of the vessel to enable her to be steered in any desired direction. types - spade; balanced;semi-balanced; barn door; single or double plate etc... materials - wood; steel; alloy.; FRP (hollow hydrofoil).
Rudder brace (/band)
– horizontal metal bracket on the fore edge of a rudder holding either the pintle or gudgeon.
Rudder head
– upper part of the rudder stock.
Rudder hole
– housing in the stern which houses the rudder head.
Rudder port
– housing above the helm port through which the rudder stock passes into the vessel.
Rudder post
– vessel’s stern post when the rudder is hung on it.
Rudder stock
– stout vertical beam to which the blade of the rudder is fixed.
Rudder stops
– wood or metal projections on the rudder or stern post which stops the rudder from turning more than 40o to either side.
Rudder trunk
– housing for the rudder stock running from the helm port to the deck where the rudder quadrant or tiller is mounted.
– a shaped expanse of fabric used to exploit the force of the wind to drive the vessel. Square sails hang from timber spars (yards) across the line of the keel; fore and aft sails are set on gaffs or stays along the line of the keel.
Sail locker
– stowage for the vessel’s sails.
– vessel’s main accommodation.
Scarph (Scarf)
– join two pieces of wood by thinning the ends and making them overlap without increasing the thickness of the joint or requiring a butt strap.
Set up
– to take up the slack in standing rigging.
– rope or wire rigging supporting a mast laterally running from masthead to side of vessel.
– outside plates or timbers of a vessel.
– a framework over accommodation or engine containing a clear glass panel allowing light/air to the space below.
Stem head
– upper end of stem post.
Stem post
– strong timber forming the foremost part of the vessel’s frame rising from the keel.
– the rear end of a vessel.
Stress crazing
– fine cracking of the gelcoat caused either by impact, load stress from fittings or hard spots. This is a condition that should be carefully repaired to avoid water ingress and where possible alleviated to avoid re-occurrence.
– vertical casing forming three sides of a square around a mast within which a mast is stepped and clamped. In smaller vessels the cheeks of the tabernacle extend above the deck allowing the mast to be pivoted on a pin.
Thames Measurement
Thames tonnage = [L – B] x B x 0.5B
Where L is the Thames tonnage length from fore side of stem to aft side of stern post (or fore side of rudder post), and B is the beam to the outside of the planking or plating. All dimensions are in feet.
Thunder shake
– a fault in timber that runs across the grain commonly found in mahogany and usually caused during felling. Renders the length of timber useless because, although difficult to see, the timber will fall apart under stress.
– non structural, transverse plank forming a seat in a small boat or dinghy.
– water tight without leaks.
– wood or iron bar fitted into the head of the rudder for the purpose of steering the vessel.
Toe rail
– length of wood fastened around the edge of the deck to prevent the loss of small items overboard.
– a rail (usually a hand rail) on the counter of a vessel (the stern rail).
– an inward curve of the topsides found in some vessel designs.
– section through the hull parallel to the surface of the water when afloat. ‘Load waterline’ is the section at the waterline at which she is designed to float.
Weather deck
– any deck which is not protected from the weather.
– machinery used for raising the anchor and chain cable.