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Read on, and let Natural Handyman nail down your concerns... while hammering home a point!!

Nail sizing... or the rule of "don't hit your" thumb

Well, now that I have admitted that size does count, what more is there to say? Not a lot, really... just a philosophical point to help you do your best work every time!

The rule of thumb with nails... 2 points if you get the pun... is that you should choose a nail that is three times as long as the thickness of the material you are fastening.

If you want to hold 1/2" drywall to a stud wall, the length of the nails should be at least 1 1/2". This is a reasonable guide most of the time. When nailing very thin materials into wood, a minimum of 1/2" of penetration is necessary.  If the thin item is holding a heavy item (such as a metal bracket that will hold a seventy-five pound bucket of buffalo chow) the nail of choice should penetrate 1 1/2" to 2".

If you are attaching something with nails through drywall or other soft wall covering such as homasote, rigid insulation or corkboard, the thickness of the wall covering should be added to the optimal nail length, because these materials do not offer much additional holding power. To nail a 3/4" thick wooden shelf support to drywall, you should use nails no shorter than 3/4" + 1/2" + 1 1/2" = 2 1/2" to 3".

A penny for your thoughts...

Common, box, and finishing nails have their own size code. Nail lengths are measured in pennies, the symbol being the letter small "d".  I can never remember the penny sizes, nor am I particularly interested in remembering them. But, for posterity and reference, here they are:

2d = 1 inch
3d = 1 1/4 inches
4d = 1 1/2 inches
5d = 1 3/4 inches
6d = 2 inches
7d = 2 1/4 inches
8d = 2 1/2 inches

9d = 2 3/4 inches
10d = 3 inches
12d = 3 1/4 inches
16d = 3 1/2 inches
20d = 4 inches
30d = 4 1/2 inches
40d = 5 inches

If you are trying to see some logic in this, don't bother. Think of it as the nail-equivalent of using the "foot" as a measurement of length, with it being divided into 12 inches, and a yard having three feet. No logic... it just is!

Specialized nails...

There are, of course, specialized nails for different materials. Drywall has its own nail. So does pressure-treated wood, roofing shingles and vinyl siding. Some nails have very wide heads to hold soft materials in place, such as Styrofoam boards, or very small heads so that they can be set below the surface of the wood and hidden with a filler, such as finishing nails. There are nails that are coated with rosin, or that have rings or twists in them to increase gripping strength.

Nails are made out of all sorts of metals... aluminum, iron, steel, and rustproof stainless steel. Some are coated with zinc, known as galvanized nails, to be more rust resistant. Some are hardened by heat so that they can be hammered into very hard materials, such as cement nails. There are duplex nails that have a doubled-head for easy removal in temporary work. There are also special nails for hardwood flooring, upholstery, and for concrete.

There is an entire subcategory of nails used in power nailing guns. These guns, driven by electricity or compressed air, use nails that are manufactured in strips. The technology is similar to staples, but with greater power and versatility. A nail gun can be used to install delicate moldings, install a roof, or even construct the frame of a home. They generate a great amount of force, and must be treated with caution and respect.

When you are going to fasten an unusual material... You must always inquire about special duty nails from the dealer when you buy a new or unique material. Often the manufacturer of the product will design a special nail for it. One such material that comes to mind is corrugated plastic roofing, commonly used over decks and patios, and installed over a wooden frame with special nails. These mails have a waterproof washer on them to keep water from leaking through the nail holes.

Then, you will be sure that you are using the correct fastener, and your project and the materials will last their longest.

Predrilling for nails...

Predrilling is the process of drilling a hole for a nail or screw before installing it.  The hole is made slightly smaller than the body of the nail or the thread diameter of the screw.  In fact, many folks are under the mistaken impression that predrilling  is reserved for screws. Not true.

Fortunately for carpenters, predrilling is not generally necessary for rough framing.  Instead, you should consider predrilling whenever there is a chance of cracking the wood, and that the cracking will make a difference, either structurally or aesthetically.

For example, I would recommend that you predrill for small 4d and 6d nails placed near the edges or ends of thin wood moldings.  The same advice stands for larger 10d or 16d nails in 2x4 studs or pressure treated decking or railings.  You might not care if the very end of a wall stud splits slightly, but you would be miffed if you were to crack  a piece of oak railing by nailing too close to the edge.

When working with older wood, which is often very dry and sometime unusually hard, such as with antiques, salvaged moldings and barnboard, predrilling should be considered for all nails if you encounter splitting or cracking. I have found that some boards (even "new" wood) just love to split... recognize this early and save yourself a lot of patching or wasted wood!

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