Types of Nails and Screws and Their Uses
Most small items of workshop stores, such as hinges, door-catches and handles, bolts, etc., are only obtained when they are required for a specific job. Workshop stores which should be kept in stock are those in general use … nails and screws. There are many different kinds of these types of securing materials, and each of them do a different job. Main types are described below, and the use of the correct nail orfor the job is specified in the instructional sections.
Some of the most common nails in general use are wire nails (also known as `French’ nails). These are circular nails with flat round heads (all the nails described are illustrated below in Image 1).
Wire nails are made in lengths from 1/2 in. to 6 in. and are obtainable in bright steel finish, or galvanized for outdoor work.
Oval wire nails are used instead of round nails for better quality work; the heads are easier to sink below the surface of wood and there is less likelihood of splitting. Finishes and sizes are from 1/2 in. to 6 in., bright steel or galvanized.
Lost-head wire nails are round in shape with very small heads that leave only a very small visible hole when they are punched in; they are obtainable in bright steel or galvanized finishes in sizes from 1/2 in. to 4 in.
Cut nails have rectangular shanks with different shaped heads; in this group of nails are cut clasp nails which hold very firmly — made in lengths from 3/4 in. to 8 in. — cut floor brads used for fixing floor-boards, with square ends which cut through the grain splitting the wood — made in lengths from 1-1/2 in. to 3 in. — cut brads (also known as ‘joiner’s brads’) are the same shape as floor brads but lighter — made in lengths from 1/2 in. to 3 in. All cut nails have a black iron finish.
Panel pins are fine nails with small heads which are easily punched in and leave very small holes — obtainable in lengths from 3/8 in. to 2 in., bright steel or copper finish, also obtainable in copper.
Wire lath nails have fine shanks and large heads, obtainable in galvanized finish only, in sizes from 3/4 in. to 1-1/4 in.
Cut tacks (commonly known as ‘tin-tacks’) are sold in sizes ranging from 1/4 in. to 1-1/4. Generally with a blued finish, they are obtainable in tinned, black iron and galvanized finishes, and also obtainable in copper.
Springs are small headless nails used for reglazing a window, securing lino, etc. — black iron finish in 1/2 in. and 3/4 in. lengths.
Brass pins are used for securing small fittings; in sizes from 1/4 in. to 1-1/4 in.
Roofing nails (sometimes called ‘nails’), mainly used for securing sheets of corrugated iron, have twisted shanks that turn in the wood when driven in — sizes from 3/4 in. to 2-1/2 in., galvanized finish.
Wire clout nails have large heads; used mainly with fabrics (upholstery, roofing felt, etc.), in sizes from 3/4 in. to 3 in., bright steel or galvanized finish.
This by no means exhausts descriptions of all types of nails, but those listed above are in general common use. Nails are purchased by weight except some small nails — tacks in particular — which are bought by the packet. Buy nails as required — they are most easily stored in glass jars with screw tops. Never use bent or rusted nails; nails will bend when driven if the hammer is not held properly, as shown in Image 2 (above right), and used with an easy wrist movement and a clear arc of the hammer head. When two or more nails are used in the same piece of wood they should slant as shown Image 3 to secure a better grip. If the wood splits easily, start the nail hole with a bradawl, cutting the hole across the grain, or cut the point off the nail.
A screw is probably the most useful item of stock. Apart from screws for special purposes there are three main types named by the shapes of their heads. These are round-head screws, raised-head screws and counter-sunk screws (also commonly referred to as ‘cheese’ heads). Screws are manufactured in a variety of materials and surface finishes; the common wood screw is of mild steel, other materials used for screws are brass, copper, aluminium and gunmetal. Finishes include bright steel, Berlin blacked, tinned, galvanized, blued, nickel-plated, brassed, and coppered, etc. Mild steel andare obtainable in a wide range of lengths and thicknesses. The less-used screws with fancy finishes have a limited size range. The size of a screw is given by its length and thickness of shank (gauge). The length of screws is the distance between the point and the widest part of the head; the gauge is the diameter at the top of the shank and all classes of screws are made in gauge numbers from 0000 to 50 — the lower the gauge number the thinner the screw — gauge numbers outside 4 to 12 are not often used. The handyman’s workshop stock should include the following countersunk screws: 3/8 in. No. Fours, ½ in. No. Sixes, 1 in. No. Eights, 1-½ in. No. Tens and 2 in. No. Twelves. Screws are sold by quantity, in dozens or grosses; the most economical way of buying screws is by the gross, in small cardboard packages which bear the length and gauge number.
Screws are driven with a screwdriver; the width of the screwdriver blade should be of a sensible size to fit snugly in the turning slot cut in the head of the screw. It should not be wider than the width of the screw head, but may be a little narrower. The correct method of housing a screw is shown in right in Image 1.
First a hole is drilled to take the thread; the top of this hole is enlarged by redrilling with a bit of greater diameter, and the top of the hole is finished with a countersunk bit. A simple table of housing holes for common sizes is given below:
|Gauge Number of Screw||Diameter of Thread Hole||Diameter of Clearance Hole|
|4||5/64 in.||1/8 in.|
|5||5/64 in.||1/8 in.|
|6||5/64 in.||5/32. in.|
|7||3/32 in.||5/32 in.|
|8||3/32 in.||3/16 in.|
|9||1/8 in.||3/16 in.|
|10||1/8 in.||7/32 in.|
|11||1/8 in.||7/32 in.|
|12||1/8 in.||1/4 in.|
Small screws inmay be started with a bradawl, using the blade to cut across the grain. Screws should be lubricated before driving them by dipping the thread in mineral oil or tipping them with soap; this preserves the metal against rust and makes the screws much easier to drive home. Brass screws are quite soft and easily snap across the top of the thread when driven into hard wood; drive an iron screw in first, withdraw it and drive home the .
A neat finish can be given to screw heads that show in the finished job by using a screw cup, a form of shaped washer with a countersunk centre (shown in image 1 – top ).