This handy little tool removes the hard 90 degree edge found inside the pen tubes and is used prior to assembly.  Once you are at the point of assembly you take the pointed end of this tool, insert it into each end of each pen tube and twist - the cutting edges will bevel the edges of the tubes.  The beveled edge aids in assembly and guides the tip, transmission, end caps as well as the upper barrel onto the lower barrel (transmission) without having to worry about galling or shaving the plating from the parts.  I demonstrate how simple this tool is to use in my video.

The outside of the pen tubes can also be chamfered.  In the event you experience a 'blown' blank the tube can be salvaged by trimming off the remaining  wood and glue.  In most cases a small ridge if brass will be found on each end of the tube which is a result of the cutting action caused by your pen mill.  Insert the tube into the three-legged end of the chamfering tool, twist and the ridge is gone.

This tool is made of hardened steel and it will last you a lifetime.  I personally have one of these tools and it has chamfered well over 10,000 pieces of rifle and pistol brass cases over the past thirty years.  Once you try it I know that it will become an absolute necessity in your pen tool inventory.  The chamfering toll sells for $15.49.  Click Here to order.