One of the major design flaws of the new Wacom Cintiq Pro Versions (at least for the 16" and 13" versions), in my opinion, is the lack of VESA mount support. I have the 16" version, and it's big enough that I wanted to use my Ergotron with it. However, Wacom didn't think I should be able to us anything other than their little kick stands which are not only annoying, but forced me to put my keyboard off to the side, which in turn puts a strain on my shoulder in a very specific place, and caused me to have some pretty bad shoulder pain. So I came up with a way to mount my Cintiq Pro 16 using some brackets.
In doing so, it made it difficult to place my pen in the pen holder without sliding my screen back and forth in the brackets because the original pen holder was oriented left to right, and the brackets got in the way.
So dusted off my digital calipers and opened up Rhino, and to got to work designing a new Pen holder. I also decided now was a good time to buy a 3D printer. So I ordered that as well. My first version was also my first 3D print, and so the results were less than desirable, but still I was able to glean some info from the print in order tp make improvements to the design so that it fits the Cintiq a little better.
After printing V2 I knew I needed to round the edges a little more, but I also noticed that I could easily modify the design to accommodate two pens. I own a regular pen and a 3D pen so this would be a nice benefit to me.
This is V3, and I need to make a few small tweaks so that I don't need to do any sanding at all after printing, but it fits snuggly without any wobble and fits both regular and 3D pens. While the 3D pen has a smaller diameter it still fits nicely, just a little further recessed.
Wacom sells their single version for $6 + $10 shipping. I plan to sell these soon for $15 with shipping included.