2017-12-12 Update: A new snap on filament guide is now available: https://www.thingiverse.com/thing:2710135

This is a 608 bearing based spool holder that snaps securely on to popular aluminum extrusions used by a variety of 3D printers. Parts for 2020, 2040 and 3030 extrusions have been included.

Why I'm a big fan of this design (inspired by remix source):

• Simply put a spool on or lift it off. No rods, screws, nuts, etc.
• Easy to snap on, off or re-position as needed
• Bearing based for smooth filament feeding
• Ideal for direct drive extruders like the Titan Aero as the filament is fed from above

I deliberately avoided adding notches to fit into the extrusion channels to avoid compatibility issues between v-slot and t-slot. This design also won't interfere with belts or cables in the channels.

The complete kit requires:
4 x 608 Bearings (AliExpress, Ebay, Amazon) or take the bearings out of fidget spinners
2 x Spool Brackets for your extrusion dimensions
2 x Side pieces

I designed these parts with tight tolerances:

• 0.0mm on the bearing so it should be held securely in place with only finger pressure to mount it.
• 0.1mm on the extrusion dimensions for a tight snap fit and minimal wobble.

Although it should be a good fit, If you feel like it's a little loose:

• Use glue.
• User Ruwaa has a make listed here where they used nuts and bolts (great idea!): http://www.thingiverse.com/make:406961

It was designed in OnShape so anyone can modify/remix the parts or export them to another format from here:
https://cad.onshape.com/documents/29eb71db69e1bb7318d53beb/w/42585bfe3de101322142941e/e/df372655fda7ed3c82d11cde

If anyone wants a version for a different sized extrusion, just let me know in the comments.

Please share your makes!