quick question

mikeyjw600

when drilling a screw into wood or drywall, i see some people create a hole with drill bit, then screw in the screw. i see others not use a bit and just screw right into the wood, drywall. why do they use a drill bit to make the hole first? is that the correct way?

fabrk8r

A pilot hole is necessary when the screw might split the material or when the screw might break from the hole being too tight.

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mikeyjw600

So the pilot hole is always going to be smaller than the screw size right?

DangerMouse

I almost always pre-drill if screwing into hardwood. Rarely if ever with soft woods like pine.
And I size the drill bit to the inner shank of the screw. Although sometimes I drill so the screw slides in and out easily (and usually countersink) if I'm locking to something behind the piece. (like trim work)

DM

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troubleseeker

In addition to a pilot hole to help prevent splitting, it also requires much less torque to drive the screw. The second situation for a hole is known as a clearance hole. This is when the hole in the first piece of wood is drilled large enough to alllow the screw to pass through witho out have to be threaded through the wood. This allows the threads to bite only in the second piece and assures that the two pieces will be drawn tightly together, eliminating the possibility that the screw will push the two pieces apart, as sometimes happens when you thread through the first piece also.

Not drilling pilot holes in hardwood will result in much frustration from twisted off screws or cammed out heads.

NitroNate

in addition to what others are saying, you have to consider the age of the wood. new lumber is still soft and contains a lot of moisture, any pine or cedar will take a screw or nail like butter. however, once the wood dries it will be much harder to screw the nail and much more likely to split the wood in the process.

i always drill a pilot hole into old wood. with osb or plywood, i typically don't bother because the wood is thin enough and is not as likely to split since it's engineered.

if you are in doubt, drill a pilot hole. it takes a little extra time but it can never hurt, as long as you drill it the right size.

mrgins

even if you screw into soft wood with a higher moisture content, the wood can still split as it dries