This is a somewhat customizable drytower to house silica gel pellets. It uses a table tennis ball as float to prevent backflow of ambient air. I plan to use this device to keep ambient moisture out of an unpressurized liquid nitrogen tank. Escaping dry nitrogen gas should constantly purge the pellets and keep them dry for a long while (hopefully).
Pause the print at about 50mm to drop in the ball (something heavier might also work). I glued all the parts together except the upper ring (so pellets can be replaced). There is no light shining through when the ball sits in closed position, so probably it will work.
EDIT: Added a simple hook to affix this vertically to an 8mm slot 8020 profile with a single M4x12 screw. The T-slot nut is a remix of https://www.thingiverse.com/thing:19885 by whosawhatsis.
You can customize the acrylic tube outer diameter, lower inlet outer diameter and fastening option (2xM5 screws, just a slit as shown, or nothing). The provided stl works with a 60mm diameter acrylic tube and a connecting hose with 12.5mm inner diameter.
| drytube.scad | 3.7KB | |
| drytube_cage.stl | 1.0MB | |
| drytube_connector.stl | 721.6KB | |
| drytube_holder_vertical_M4.stl | 169.8KB | |
| drytube_lowend.stl | 128.7KB | |
| drytube_topend.stl | 137.7KB | |
| drytube_tslot_nutM4.stl | 35.9KB |
