Auto-Lock Spool Holder with Magnetic Brake for Original Prusa Enclosure

I wanted to solve the problem of self-unwinding of the filament and at the same time I wanted to clamp or release the spool with one hand. Another requirement was the use of commonly available connecting material. It was a challenge to integrate the entire clamping system into a diameter of 49mm with an acceptable overall length. Of course printable and without supports and the hexagonal core proved to be the winner. And it works.

Videos of function:

Thanks for yours posted prints and likes.

Features:

• automatic locking by inserting the spool
• operated with one hand
• magnetic brake against unwinding of the filament
• wide range of settings
• no supports needed

Recomended:

• print of PETG
• layer 0,2mm, 3 perimeters, 20% infill gyroid, random seam position
• fan enabled for bridges
• outer_body_49 print with brim inside

Instructions:

• print orientation as the parts uploaded
• lock_arm and lock_lever must be printed 3 times
•  
• all bolted and sliding parts must move smoothly
• insert the magnets fully into the holes

You need:

Neodym magnets:

31pcs 10x6x2mm block

3pcs 20x6x2mm block

3pcs 5x5x2mm block

4pcs 6x2mm cylindrical

2pcs 6x4mm cylindrical

(note: 5x5x2 magnets can be replaced by attaching the cover_ring part with glue.)

Screws:

1pc bolt M8x125mm with cylinder head for Allen key 6mm

7pcs M3x4mm

1pc M3x8mm

3pcs M3x20mm

3pcs M3x12mm

3pcs M3x35mm

Nuts:

1pc self-locking M8

1pc M3

Bearings:

3pcs 608-2Z

Assembly instruction:

• https://drive.google.com/file/d/1MXKVDAgGqpj_q3hpU_lAMTzfOWWz4cTa/view?usp=sharing
• in the first step, don't insert the magnet into the bs_holder part
• continue according to the instructions
• finally screw to the Original Prusa Enclosure using the fasteners used to attach the original bracket.
• All 10x6x2mm magnets can be removed thanks to the prepared holes by pressing out with a 1.5mm Allen key (except for the magnets in harmonica_damper). The 20x6x2mm magnets can be pushed out with the help of a 2mm Allen key.

Inserting the spool and setting for a specific width of spool:

• screw the adjustment_ring towards the angry_holder, but at most up to the distance where the adjustment_ring touches the magnet_ring (for the possibility of full locking mechanism)
• clamp fully(second click) the spool into the holder
• screw the adjustment_ring pointing to the spool so that it does not rotate in the holder
• done

Note:

• the brake is designed to fit on the right side of the Original Prusa Enclosure
• the brake works even without the harmonica_damper part, but with an unwanted clicking sound