DIY Tip of the Day: Enlarge a Spade Bit Hole. If you’ve ever drilled a hole too small with a spade bit and wanted to redrill it to a larger diameter, you know the meaning of frustration. To get the hole larger, file the sides of the larger spade bit at a 60-degree angle. Leave the edges of the filed areas sharp so they cut as you push the bit in with your drill. Hold the drill firmly as you carefully expand the hole.