Hole Saw

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The other options for drilling out larger holes include using a 1/2 in. drill or a spade bit. The 1/2 in. drill is an expensive route to take, with the drill itself quite expensive, and the bits running about $30 a piece. A spade bit sometimes just won't cut it for the task. A hole saw, on the other hand, can be as cheap as $5, and will fit as a bit on most standard 3/8 in. drills.

Again, hole saws are very affordable, with the cheapest of them available for as little as $5. You may, however, want to consider picking up a bimetal hole saw if you intend on using the tool repeatedly or on a harder material such as any kind of metal. Before you purchase a hole saw, however, be sure that your drill will have enough power to drive the saw properly. Almost all corded drills will have the power needed to drive a hole saw, but some cordless drills will fall short in this department. Be sure that your cordless drill is at least 18 volts, or you'll find yourself without enough power.

When operating a hole saw, there are couple of things to keep in mind to ensure success. First of all, you must have the drill bit of the hole saw extended beyond the ring of teeth. If the bit itself does not engage wood, the saw will not stay put, and will instead chew up the surface of the wood. To drill out the smoothest hole possible, you should drill from both sides. If you need to enlarge an existing hole, you'll need to clamp some plywood over it so that the drill bit will have something to engage with.

Hole saws can be found at most any local hardware or home improvement store.