Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:2603007.

Here is my system for feeding filament. It uses Bowden fittings to connect the dry box to filament sensors on the printer. Be careful to keep the PTFE tubes short. I'm planning on switching to Capricorn PTFE soon, I hear its even slicker than regular PTFE.

You can ignore the tabs. I originally designed it to be spring loaded, instead I tightened up the holes that the copper pipe goes through. Its more of a friction fit now. You will need to sand the inside of those holes slightly depending on printer tolerances.

This thing uses 2 F608ZZ bearings with the shoulders out along with M4 (I think) nuts and bolts.