Gravity Rewinder Drybox

This is an experimental gravity powered spool rewinder that fits inside of a Rubbermaid 21 cup drybox container.

Discontinued and not recommended.
New Version found here.
My testing shows that it only works about 19 out of 20 tool changes. It has three problems.

1 Sometimes it will not rewind and that will cause the filament to tangle up.

2 Sometimes the spool hub falls out of place and causes the spool to get stuck.

3 Sometimes with full spools it will pull the filament too far out of the back of the MMU2(s)

Print instructions

Please ask questions and give feedback.

How it works:
A 200 mm Diameter spool has about 50 mm of free space in the rubbermaid 21 cup container. So I reduced the diameter of the axle so we can get about one and a quarter rotations on the spool. I think this is enough in nearly all cases.

Demo Videos

Rewind In Action

How to load the rewinder

Spool Hubs
Different spool brands will have a different inner diameter for the spool. I have uploaded a single 3mf file with MANY sizes of spool hubs. If you want a specific size that isn't already provided please ask me in the comments. I will add it.

I will upload STEP files if requested. But here is the link to my OnShape document with all the CAD files including the parametric Hub.

Build Materials
(Quantities listed are for a single build)
3x M3x16 screws (or longer)
3x M3 nut (or lock nuts)
4x Drywall screws (for Enclosure Mounts)
2x PC4-M10 Passthrough connector
1x PTFE Coupler
5 inches of 3mm ID 4 mm OD PTFE tubing. (3 mm ID needed for reduced friction near the dry box.)

Tools
1/8 inch or 3 mm drill bit
5/32 inch or 4 mm drill bit

Print Settings
I used PETG at .2 mm for everything. The Spool Hubs work well with the flexibility PETG offers.

The Right Side saddle mounts are used to mount a fifth drybox to the RIGHT side of a LACK enclosure. If you wish to mount onto the LEFT side please mirror the models in your slicer first.

The PTFE tube cap is used to plug the Tube for long term storage. It was printed in NinjaFlex or TPU with .2 mm layer heights.