When I first started my carpentry apprenticeship I wasn't sure which were the most popular drill sizes I'd use and needed to buy. There are so many different types available and they vary in price so much I didn't want to go spending lots of money on drill bits I wasn't going to use. This page lists which ones I use for drilling various types of holes.
Small holes in wood
Small holes in wood are generally pilot holes for screws and even for nails, when I'm banging in nails close to the end of a length of timber that I don't want to risk splitting.
When drilling small pilot holes in wood, I use Dewalt brad point bits. The most common drill sizes I use range from 2-10mm. I bought a set and just replace the worn ones as necessary. A set of drill countersink bits is also really handy for finish carpentry work. Using a drill and countersink bit prevents the wood from splitting when burying the screw head enough for it to be filled over by the decorators.
Drill bit for Medium holes in wood
For medium holes I have a 15 piece set of auger bits that range from 10 - 25mm. Mainly used in finish carpentry, the most popular sizes I use are 16, 18, 20, 22 and 25mm. Drilling mortice locks and mortice latches is possible with flat wood bits but auger bits are easier to keep straight while drilling - important during finishing work.
I use a set of flat wood bits mainly during framing carpentry, they're shorter and therefore easier to get in to awkward spots between studs and joists etc..
Drill bits for Large Holes in wood
Hole saws are the best option for drilling holes in timber larger than 25mm. Whilst expensive ones are available individually it worked out cheaper for me to buy a set.
I mainly use them for drilling holes for pipes in pipe boxing's and when fitting kitchens, but they come in handy for lots of other jobs too. Because I box pipes in plywood I don't really need to spend loads of money on them. If I was a plumber I'd invest in a more expensive all purpose set, but I found a 9 piece set of faithful hole saws that were half price and are more than sufficient.
They also sell adjustable hole cutters there for accurately cutting odd sizes.
When the holes get too big, its easier to use a jigsaw or router with a special attachment.
Popular drill sizes related pages
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