Start with the coarse grit on a board, and continue up through the rough sanding, application of the CA glue, fine sanding, wet sanding, and polishing.
A little rounding of the edges of the upper barrel is a good thing. The corners on the lower barrel should be kept as sharp as possible.
Scribe two shallow lines, about 3/32" from the end of the upper barrel and the same distance apart.
I am using a Spear Point tool. A small flat parting tool, an awl or a nail will work as well. Grind the end of the nail to a uniform point.
Burn in the lines with a piece of fine steel wire while the lathe is running at a fairly high speed. The higher speed gets hotter faster. Use two pieces of dowel for handles. DO NOT hold the wire with your fingers.
The diameter of the wire that works best is about the same diameter as that in a "twist tie" that is used for sealing trash bags and bread. I have used these by stripping away the paper, and holding them between two pairs of pliers.
Lightly sand the burned area with 600-grit.
Proceed with the application of a finish as was described for finishing the "Slim-Line" pen. All of the finishing steps are the same.
This pen was turned and finished without using the stepped bushings in the center.
This pen used the stepped bushings in the center.
The barrels are removed and assembled into a pen using the same steps as shown for the assembly of the "Slim-Line" pen, except that the center band is omitted.
The finished pens are shown here with the "Slim-Line" to compare their differences.
The pen in the center was done "free-hand" without the benefit of a bushing in the center for the diameter. The bottom pen is the one that was made with the center bushings.