Tube Length(s)and Diameters
When finished the blank will be very thin. It is important to match the drill bit to the brass tube size. If the drill bit is too large you may not have remove all the blank material. The thinness of the material makes it imperative to paint he tube when using acrylics.
This pen style isn't very well suited to snake skin or acrylic overcoats. If snake skin is used it is imperative to leave the blank oversize by about .050" or you risk exposing the snake skin.