Today I added standard pen to my Waiter - creating 84 plus scales. I used the file on 111 Tradesman to file down the channel in the back scale. The width of 111 file seems to be just perfect fit for this purpose. In the my first attempt I did not create the channel deep enough so when I put it back the pen did not fit so I had to remove the scale one more time to remedy it but now it all fit nicely with just enough friction to keep the pen in.At the end I sligtly filed the plastic head of the pen to be better aligned with the scale.
Thanks for the tip - now I know. Actually your work looks really neat!
z1913 and kamakiri, those are just plain cool!