One of the most versatile attachments you can get for your drill is the humble burr grinder. These are used to bore into wood or other materials any time you want to carve, smooth, or otherwise remove material without actually punching a hole in it. They’re also good for widening pre-drilled holes that might be difficult to re-drill.
There are several different shapes of burr grinder. You can get a ball grinder, end cut cylinder grinder, ball nose cylinder grinder, pointed tree grinder, ball nose tree grinder, and numerous other shapes. Each of them allows you to grind at different angles and in different patterns, so it’s good to have a full set. There are also several file grinders that can be useful for taking the sharp edges off metal.
The burr grinder gets its name from the sharp metal burs, which dig out bits of material as the bit rotates. These bits are relatively cheap and can be useful in all kinds of situations. There are also smaller, ⅛-inch shank burr grinders that make popular attachments for Dremel-style rotary tools. Those are good for carving tasks that require finer motor skills, but the larger ones can take advantage of the extra power you get from a drill to remove denser material easily.
