Follow these tips to make sure your drill doesn’t make a mess of your woodwork or masonry project.
You’ve probably noticed that when you drill through wood or even bricks, the drill bit can make a mess when it pops out of the other side. This splintering or fragmenting is called ‘blowout’ and it leaves an unsightly exit wound. Here we discuss what causes blowout and how you can prevent it.
With timber, blowout can occur with normal wood bits but is especially common with big bits and spade bits (the flat drill bits with a pointed tip). The trick with a spade bit is to drill first from one side and then the other. Do this by starting from the first side but stopping as soon as the tip breaks through the other side. Now you can see where the middle of the hole is from the other side. Flip the wood over and drill from this side now until you break through to the hole drilled from the first side.
With normal wood bits it can be hard to know where to drill from the second side, so it’s not practical to use this ‘half-and-half’ technique. In this case, clamp a piece of scrap wood to the bottom of the piece of wood you are going to be drilling through. When you drill through the actual timber and into the scrap piece, the scrap piece will support the wood enough to prevent blowout.
When drilling through masonry you can also use the half-and-half technique, but with a slight difference. Because masonry bits don’t have a point, it’s hard to know exactly where your bit is going to emerge from the brick, so you don’t know where to drill from the second side.
To solve this issue, use a smaller bit. So, if you are drilling a big 22 mm hole through a brick wall, for example, first use a 6 mm drill bit and drill all the way through the wall, easing off on the pressure when you get close to going all the way through.
Once you have drilled the 6 mm pilot hole, change to the 22 mm bit and follow the pilot hole, drilling most of the way through from the first side and then finishing off the hole from the second side.
Builders have all the drills and drill bits you could ever need in stock, both in-store and online.
Browse 1000’s of products available to you. Select your country to Shop Online.
