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Consumables - Nails (back to index)

A Bit About Nails

Nails are a simple and cost effective way of joing two pieces of timber or similar material. Generally for a first class joint, either joinery, a timber glue, bolts or screws would be used, but the humble nail works and will be with us for a long time to come.

For those interested in such things, the theory behind a nail entering into timber is that it first separates the tiny wood fibres, forcing them into a new formation which will then grip the nail. The nail is effectively held in this 'interference fit' which holds for the inext few hours. Soon after, the moisture in the timber fibres is squeezed out thus lubricating the nail, so for up to a day or so the nail's grip actually becomes less. Over the next day or so, this moisture dries away from the nail, the grip again becomes firmer, and there it stays for the duration.

Straight in Vs Skew & Dove Nailing

Nails can be insertered in two ways. Straight (90 degrees to the surface) or dove nailed (at an angle), dependent upon the two pieces of timber to be joined.

For both types, it is important that the most suitable type and length of nail are used. Lengthwise, generally at least half of the nail should be in the timber being nailed to. For decorative or non-structural timber, this is generally not an issue as a straight nailing approach is used and the piece being nailed is typically thin in comparison to the piece being nailed to.

For a 75mm joist being nailed to a 100mm bearer, the nail would theoretically need to be 150 mm. This is a big nail, but the solution is to skew nail through the side of the beam, at say 60 degrees, halfway up the side of the joist (see figure A below) effectively putting half through the joist and half into the bearer. Skewnailing is of course the only way to nail a vertical beam to a floor beam or bearer, and in the third example below the bearer has been slotted to ensure an even more rigid fit between the two pieces of timber. Additionally this accurately locates the vertical, because skew nailing tends to move the timber being nailed sideways. This slot is easily made with a (tenon) saw and hammer and chisel, or if you have one, a router.

Another advantage of dove and skew nailing is that whereas a piece of timber held by a straight nail can be easily pulled away, two angled nails crossing each other (see examples two, three and four above) will very effectively lock the timber pieces together.

Generally, use the straight approach for non-structural timber, and the dove or skew nail for structural work.

Plain Heads & Lost Heads

Plain heads, by virtue of their larger diameter head, should retain nailed timber better than bullet heads, which can 'pull through' due to the almost non-existent top.

Generally use a lost head where the nail is on the outer piece of timber and needs not to be seen, and a plain head where the timber to be fitted will be covered by wallpaper, plasterboard or a further trim. For instance door frames can be round head nailed to the wall structure, then covered over by the door jams. Round heads are the choice for most structural work, even though skew nailing adds much more strength than the head of almost any nail.

Lost heads can be discreetly hidden by punching them further in with a nail set (or nail punch), then applying a small amount of filler prior to painting. Nail sets are available at many hardware stores, and have a small recess in the end that fits over the nail head. Striking with the same hammer you used for the nail will push the nail in far enough to overfill. Ensure you have the correct size punch for the nails in use, as this results in the minimum size hole, and prevents the punch slipping off the nail.

Nail Set

Nail set - used for punching nails in that last bit to enable wood filling over the nail's head. Obviously a tool, but worth highlighting here because many people are not aware of their availability.

Though it cannot be seen here, the point of the nail set is concave (dented inwards) to ensure it sits easily upon the head of the nail.

Liquid Nails

Construction adhesives, often referred to as liquid nails, are applied as a continuous stream, about 3 to 5mm diameter along the piece of timber to be fitted, then nailed in place to hold until the adhesive sets. These are very useful for skirting boards and decorative panels, and well worth experimenting with.

Normal method of application is to apply a 3mm wide bead near the edges of the piece of timber to be connected, then press the timber in place, remove it again and lay it to rest.

Once the adhesive becomes tacky (sticky to touch, but starting to set) press the piece back in place again and secure with a few well placed lost head nails, which can then be immediately punched in. Full setting will occur overnight and the purpose of the nails is to retain the positioning over that period.

Subsequent removal can be difficult and will often damage one or both of the surfaces, but an alternative is to place a lever behind the board and apply steady pressure. Over a few minutes (sometimes) the afixed piece may move apart.

Below we cover the more common nail types and their general usage.

Plain or Round Head Nails (aka flat heads)

Plain head nails are the basic wire nail with a large flat head.
Oval head nails are less likely to split the timber being nailed.

Generally used for unseen timber (sub-floor construction, structural, wall framing) or external work (fencing) or on most rough sawn timber projects.

Lost Head Nails (aka bullet heads)

The round lost head has the advantage of being easier to conceal than a plain head, while the oval lost head is less likely to split timber than its round counterpart. Both can be punched in with a nail set.

Generally used for seen timber work, architraves, shelving, cupboards, and generally on most finished (planed all round) timber projects.

Note in our photo, the left side nail is face on, whilst the right side is edge on. Both nails are the same size.

Ring Grip Nails

Ring shank or ring grip nails are a much securer nail, but once installed they are (very) much more difficult to remove if installed incorrectly or later maintenance is required.

Generally used for some roofing materials (see left screw and matching waterproof seal) and often are used to better secure plasterboard to framework.

 

Masonry Nails

Masonry nails are a quick way to mount timber on masonry; an alternative to wall plugs.

Generally suited to decorative timber trim, such as picture rails and skirtings. (Architraves normally nail direct to the door frame).

 

Panel Pins

Panel pins are excellent for pineboard and some timber panels, lightweight and small.

Generally used for afixing timber panelling, such as strip softwood sheets on dado panelling.

 

Tacks

The humble tack.

Generally used for fixing carpet and other fibrous materials to timber.

The U nail

Best for items such as chicken wire fencing and wire fencing strands, but do not use for cords (which can wear through) or telephone, electrical or plumbing fittings.

 

Gang Nails

A flat plate with sections punched out and alighned at 90 degrees to act as an array of equi-spaced nails. Particularly good for joining timber frames, such as in roofing. Note that the gang nail secures the pieces together, but additional strength is created by addition of other roofing members and completion of the entire structure.

Please be advised: gapfilla.com does not purport to be an expert in all facets of diy, but has significant experience in almost all of the topics covered on this site. We suggest that all persons take adequate care in the translation and application of this content to their projects, particularly as projects rarely encounter identical issues and constraints. If in doubt, we suggest you seek advice from a professional tradesperson or advisor. All material copyright gapfilla.com 2005-13