This demonstration pen tube has been designed for the following pencil kit available
here:
https://www.pennstateind.com/store/PKBFPCLCH.html
To see a forum post about this particular assembly go
here:
https://www.shapeways.com/forum/t/buffalo-pencil-tube-and-assembled-pencil.97227/
For additional information consult the penmaker's interest group in the Shapeways
forum:
https://www.shapeways.com/forum/t/penmakers-and-3d-print-pen-making.80076/
A sample pen tube generated by a ShapeJS creator which may be found
here:
https://shapejs.com/products/o9nh-YQ9nSqF/view
Extra notes: This tube is overly wide and if you're using the pocket clip it helps to bend it out a bit using a vise prior to assembly. The Buffalo pencil assembly is relatively immune to tube length since there is no internal mechanism. Therefore this tube is essentially RTG (Ready To Go) since the length does not need to be adjusted for a precise fit.