See them in action. 

Modifications made as separate model. ends of channels constrict to help keep pens in the slots while moving the trays. 

Made this for a bit of a dual purpose. A way to more neatly have my pens stored but more easily accessible. As well as a display I make videos on fountain pens and have wanted one of those fancy trays to neatly display and make it easier to compare pens. 

Make sure to turn on or create a vase mode or spiralized profile. I increased my line width beyond my nozzle diameter for a bit of extra strength. Just make sure you aren't printing fast enough to exceed your printers flow capabilities. 

Silk pla's have poor layer adhesion so they may reduce durability if you decide to use them. 

I used cura with spiralized enabled 

0.3 layer height

0.6 line width

60 mm/s speeds 

30 mm/s initial layer 

Cura shows that at just under 11mm³/s flow rate

Voxelab Aquila been modified for direct drive, all metal hotend and is running klipper.