Billy IKEA Filament Spool Holder

This system transforms a standard Billy (IKEA) shelf into a practical filament spool holder for 3D printing.
The holder consists of two round rods and four side brackets (front and rear, left and right), designed to hold up to five spools vertically between the rods.

🔧 Assembly

1. Attach a rod to its corresponding two side brackets.
2. Insert the complete assembly into the Billy shelf.
3. Loosely screw the two top M4 screws into the existing holes on the side of the shelf.
4. Align the lower holes with the ones on the Billy and insert the 3.5 mm locking pins.
5. Tighten fully the two M4 screws.

All holes — for both the M4 screws and the locking pins — perfectly match the original Billy holes, so no drilling or modifications are required.

The pins can be easily removed with tweezers, allowing you to quickly disassemble or reposition the holder.

🖨️ Printing Recommendations

• Material: PETG for all parts.
• Side brackets: 15% infill
• Locking pins: 100% infill
• Round rods (printed): 15% infill and 50% infill the internal reinforcement object
• Layer height: 0.2 mm recommended.
• Supports: none