And another experiment. This one just had the aging solution applied, no digging out of the grain. The grain was so tight that I thought it would detract from the overall appearance if I dig it out.
I went ahead and glued in a tube to see how things would work, and I learned a few things.
1. With these angled blanks, they do NOT like to have the ends squared. You can see the top section with a different wood (walnut with aging/ebonizing solution). That's due to a blow out during squaring. I think it would be best to sand the ends square with these, but even though I've got one of Rick's offset lathe sanding jigs, I've not had much luck in getting the ends square with that method. So I clamped the end in my vice to support the grain as best I could while squaring with my drill.
2. With the Cortona pen kits, be very careful not to trim the brass tube when squaring. These kits are a little different from others I've turned. The top section presses in as normal, but the tip assembly only presses in by hand. The twist mechanism is very long and fits into the upper section to hold everything together. While fixing my blowout issues, I shortened the brass tube which didn't leave enough length to allow for the tip section to mate with the end of the blank. I'm curious to see how this design fares over the long haul.
3. When using epoxy, heat is your enemy. I used epoxy to glue on the segment at the top, and while removing excess wood on my belt sander, I got it too hot which softened the epoxy and ruined the hold.
4. Always be willing to spend as much time as it takes to experiment with things.