I make mostly kitless pens now and use them when I have a piece of material that is borderline on the length. I superglue them on the tailstock end of the material I am using. Then when I use my #2 center drill to create a spot for my tailstock live center support, I'm drilling into the off cut not the material for the pen. When shaping the pen, that turns off leaving only the desired pen material. I use even very small pieces, 5-6mm for this.