Like most woodworkers, I make the occasional mistake when working on a project. Some are easy enough to fix, while others are more difficult to address.
One of the challenges I encountered recently was to increase the size of a hole that was cut too small. The location of the hole had to be exact and I knew it would be difficult to accurately centre the workpiece directly under a larger bit. To solve the problem I turned to my hand-held router and a pair of router bits.
I started with a rebating bit set to cut 3mm deep. The bottom edge of the hole was used to guide the bearing of the bit as I routed around the entire circumference of the hole.
Then I switched to a pattern bit. With the bearing of the bit held firmly against the newly cut rebate, I was able to remove the rest of the waste from the hole (drawings above). The end result was a perfectly centred hole that’s just the right size.