Update:

Adjusted some tolerances on the models and added extensions so you can offset the shelves more if needed.

This disc golf shelf ends are designed to print on an ender 3 bed. Has rippled faces to keep print from warping.

Designed to use ¾ inch inner diameter 7/8 inch outer diameter tube. Press fit. If shelves are stacked there are small 3/16 holes meant for dowels to be press fit in.

The middle piece is meant to have tubes on each side and is wider and the ends are less wide and only intended for one set of tubes.

Link to the Menards one I used for tube below

https://www.menards.com/main/plumbing/hoses-tubing/pex-tubing/sioux-chief-powerpex-reg-white-pex-tubing/664x3w5m/p-3289655538082569-c-19654.htm