Nice going on the pentel conversion. I like the one on the right the best. I love seeing what others do with the conversion.
I've been making the pentel conversion since I read an article by Nick Cook. I think I made my first conversion in 2005. There were no special tooling so I improvised. I made my own "step drill" (very crude) and actually I went back to using two drill bits. At some point a member here started making step bits and special mandrels to hold the pen blank. OH!, so much easier. But, my friend, the late Rich Kleinhenz, published an article in Woodturning Design in 2012 that makes the process so much easier. Here is a
link to Rich Kleinhenz's article. Shared with permission.
Do a good turn daily!
Don