This pencil organizer that's also a giant functional nut and bolt – size M80, to be exact.

Interior dimensions: 69mm (diameter) x 107mm (height)

External dimensions (WxDxH): 100mm x 114mm x 110mm

I found that this was a nice size, both visually and practically.

This is also available on Thingiverse.

Print instructions

No supports required!

For the nut, the default (organizer-nut.stl), the threads have a 0.3 mm tolerance, which works great on my Prusa MK3S. I recommend starting with this. If your printer doesn't print with tight tolerances, there is an alternative with 0.5 mm tolerance, called organizer-nut-looser.stl.