One of the most common tasks you’ll need to learn in your DIY journey is how to change a drill bit. This is not the same for all drills and drill presses, but it can broadly be broken down into two categories: keyless drill chucks and keyed drill chucks.
Now, before we get into it, what is the drill chuck? The drill chuck is the part of the drill that holds the drill bit in place. They typically have 3 or 4 claws which tighten down over the drill bit and hold it in place.
Keyed drill chucks
To change a drill bit in a keyed drill chuck, you need a drill chuck key, which is often found with the drill. This setup is most common in drill presses, but you do occasionally see hand drills with keyed chucks too.
The key is inserted sideways into the chuck by locating the tip of the key into one of the holes in the side of the chuck. The teeth on the key should then align with the teeth on the chuck, allowing you twist the key and loosen the chuck. After you have sufficiently loosened the chuck, the drill bit should slip out vertically.
Now you are ready to change the drill bit to your new one. If necessary, widen the chuck to accommodate the new bit, and hold the bit in the middle of the chuck. Carefully tighten the chuck with the key, ensuring the drill bit stays in the centre of the chuck.
Tighten the drill bit down with the key, and remove it when you’ve finished. Many people forget! Finally, it’s worth running the drill very quickly before drilling to ensure the drill bit is rotating correctly. If it isn’t, loosen the chuck and centre it up.
Keyless drill chucks
Keyless drill chucks are a more modern design, and allow you to change drill bits much faster, and without the need for chuck keys. They are very popular on cordless drills, which are designed to be used on the go around the worksite.
To remove a drill bit from a keyless chuck, grasp the grip area around the edge of the drill chuck. With the drill speed on low, and set to reverse direction, gently depress the trigger a little while grasping the chuck grip. You should feel the chuck loosen, and the drill bit loosen in the chuck.
Put the new drill bit into the chuck, and set the drill back to clockwise (tighten) mode. Many people find it easier to first tighten the bit down by hand, which makes it easier to ensure it’s located properly in the center of the chuck. If you have a hex-head drill bit, you should ensure the flat sides of the hex sit flat against the drill chuck claws. Tighten the bit down by hand.
Once the bit is firmly hand tightened, grasp the grip on the drill chuck, and carefully depress the trigger momentarily on forward mode. This will tighten the drill down against your hand. Be sure to only do it gently so you don’t damage your hands!
Finally, run the drill quickly to ensure the bit is centered straight and true – then you are good to go.