Having a decent drill is only part of any DIY job. If you do not have the correct drill bit for the task at hand, you will be making things hard (and possibly dangerous) for yourself. You don’t need a massive selection of every kind of drill bit available, but it is a good idea to have the more commonly used sizes and types in your toolkit. For more specialised jobs, you can simply buy the bits you need when you need them. You can buy sets of drill bits fairly cheaply, but if you plan to do a lot of DIY jobs, it is worth investing in some more expensive, high-quality bits. They will generally work better, last longer and be less liable to snap or break in use.
How to Choose Drill Bits
Choosing the drill bits you need depends largely on the job you need to do. You will need different bits for drilling wood, metal or stone, and may need a variety of sizes depending on what you need to do.
Twist Drill Bits
Twist drill bits have a straight shaft and a simple bevelled tip. They are used for drilling wood, man-made board and metal. These are probably the drill bits you will use most around the home, so go for a good set of HSS (High Speed Steel) bits if you can afford it, in a range of sizes up to about 12mm. Store them in a metal case if possible, and after use, rub the drill bit with an oily rag to stop them rusting in your toolbox. Some twist drill bits specifically designed for wood have a spur point (a small spike of steel at the end of the drill bit to help keep the hole true).
Masonry Drill Bits
Masonry bits are designed to be used with a hammer action drill to make holes in walls and solid floors. They have a straight shaft with a larger “tooth” at the tip. This helps to remove dust and debris from the hole, as well as helping the drill bit to bite into the hard material. You probably don’t need to buy a full set of masonry bits as you will mostly use one of three sizes: 5mm, 6mm or 7mm. Buy some good quality bits in these sizes for your toolbox and then buy any others as you need them.
Flat Wood Bits
Flat Wood Bits are specifically designed for boring larger holes in wood. They range in size from around 6mm up to over 40mm. There is no need to buy a full set, just buy them as you need them and store them in their plastic sleeves.
Core Drill Bits
Core drill bits consist of a masonry drill bit enclosed by a toothed circle of metal. The masonry bit is designed to keep the hole true, whilst the outer ring cuts out a large-bore hole. Core drills are designed for cutting large holes in blocks and bricks, particularly for plumbing and electrical runs.
Countersink Drill Bit
This is a wide, short drill bit designed to make a cone-shaped recess in wood or metal to take the head of a screw. This allows the screw head to be flush with the material, allowing for a neater finish. Useful to have in the toolbox.
Most cordless drills come with a few different screwdriver bits, allowing you to use the drill as a power screwdriver. If yours doesn’t have any, you can buy them in small sets from any DIY store. Buy a good quality set and they should last for a long time.