I designed this back in 2019 to split 2kg spools into 1kg spools. Used to transfer filament between two spools:

• Spool ID down to 12mm
• Spool OD up to 300mm
• Maximum spool height/thickness depends on the inner diameter (at least 110mm for most spools)

👉 YouTube Video

Print all parts once. They are pre-oriented with built-in supports. Outer brim can help for the standing parts. You can use 3 perimeters for the vertical columns, but 2 is probably enough. No other special settings. I printed in PETG.

Sourced parts

• M3x30mm screw (or longer)
• 4x 6001 bearings
• power drill
• piece of 4x2mm PTFE tube, 20-30cm long
• small pieces of filament for assembly (I use nylon filament, but PETG or TPU are also good options). PLA may work as well but is more brittle

No detailed assembly instructions. Just a few glimpses in the video above.

Operation This device can be dangerous. Use it at your own risk. Do not use high speeds and avoid sudden stops! The source spool has no braking system and will continue to unwind and can tangle the filament. Do not touch the filament with an empty hand/skin while it's being transferred between spools (always use the PTFE tube). Do not try to stop a spool rotating at high speed with bare hands.

More projects at mihaidesigns.com

Supportless, support free.