I finally finished it and got it in the catalog!
My 24-Slots Acrylic Ink Pen Holder
It says it’s only for Professional Models, but there’ s no reason it couldn’t be done on an Aura or Spark too - it would just take more sheets of material as they’re smaller 
I love working with these alcohol inks, but the bottles this brand sells them in do not seal well…and I’m very tired of having ink on the outside getting all over my hands.
The updated design in the catalog can hold everything from those alcohol inks, to standard pens, to paint brushes, and crayons, and more. The clear acrlyic means you can see what you’re pulling, and the fence on the bottom both contains small items in the storage area, and gives you a spot to lean the pens you’re currently using against so (if they’re the kind that drip) they won’t drip, or roll away!
Oh yeah, and I added a kerf test so you can figure out if it’ll fit as is, or if you need to run your cut twice or use a torch to soften the acrylic before assembly!
History
Inspired by the modular pen holder design in the catalog I used the boxes.py divider tray as a start and ended here: (design removed)
In a perfect world it’d be made out of acrylic so you can see what colour you’re pulling - but for at least the short term I’m out of clear acrylic, so I’m using the cardboard one!
It’ll hold 24 objects, and then there’s an open space at the bottom (I built it a little fence so that as you’re using you can still keep them angled up - but I didn’t cut that out of the cardboard version so you don’t see it here)
These pens are 3.75" long and .6875" diameter…so longer ones will stick out more.
The pockets are ~.75" across so there’s a bit of wiggle room.
*Also note that the tabs/slots have not been optimized for any particular material, so measure before you cut!
