Dry breather for reverse Bowden print box

thingiverse

If you have a reverse Bowden setup, for every mm^3 of filament you take out of the print box, 1 mm^3 of (wet) air finds its way in somehow. If the print box doesn't have its own inlet, the wet air enters at the extruder and gets sucked along the filament that's about to be used. This provides an easy inlet for air at the print box, and makes sure that the air taken in has a good opportunity to interact with dessicant. Air comes in along the axis, fills the plenum in the center, and travels through about 2cm of dessicant before it's released into the box. When you aren't printing, it's a dessicant holder at the top of the box and does a good job scavenging water vapor from the air.