This is a fifteen cent pencil sharpener. Most of the ferrules I use are the REC Uniferrules. Since they are bored from NS stock the bottom of the inside is concave, matching the drill head. When my ferrule stations are finished, the last step is to turn down (bevel) and round over the end so that it will sit in the concave bottom. On any other ferrule with a flat, soldered in moisture seal, I would not do this.