David Isaacson and Pat Mohan offer an advanced topics seminar at the Raleigh Pen Show June 2016. 1 hour video. Seminar is based on David's article on this subject from 2012. David and Pat are generally acknowledged to have the two most comprehensive collections of Sheaffer Balance pens with special trim. See pens of this sort at David's pen website vacumania.com . Discussion can be had at the Fountain Pen Board fountainpenboard.com and at our Facebook group "Fountain Pens" facebook.com/groups/fpnuts