It is always difficult to fit plugs perfectly; any slight run-out in your drill press quill can make the holes oversize. Unfortunately, this run-out will also make plugs undersize. The combination leads to ill-fitting plugs that are very noticeable in your finished work. Snug-Plug® cutters are designed to cut slightly tapered plugs; the first 3.2mm of the plug is the stated size and then flares out at a 3° included angle.
Unlike regular plug cutters, they also shave the plug sides as they cut, producing very smooth plugs. You just tap a plug into a hole until you meet resistance, then cut off the excess. You will then have a plug that fits perfectly, with a nearly invisible line between the plug and the work piece.
These plug cutters are carefully reamed after hardening to ensure perfect concentricity. It is difficult to believe how nice a plugging job you can do until you actually use one.
Resharpening instructions included.