Prusa MK3S Extruder Cable Support (Filament Tether)

This is a simple, low-profile cable support system designed to fix the notorious extruder cable sag on the Prusa MK3S. Instead of heavy printed arms, this design utilizes the natural flexibility and springiness of a standard 1.75mm filament to keep the cable bundle neatly elevated.

It consists of two small parts:

1. Frame Clip: Snaps securely onto the top aluminum frame.

2. Cable Clip: Snaps onto the extruder cable sleeve (textile sleeve / spiral wrap).

As shown in the image, the filament acts as a perfect flexible bridge that moves smoothly with the extruder without adding unnecessary weight.

Post-Processing & Assembly

1. Print both clips (PETG or ABS/ASA recommended for durability and flexibility).

2. Cut a piece of 1.75mm filament to about 15 cm (approx. 6 inches) in length. (Adjust slightly if needed after testing the full movement range of your extruder).

3. Insert one end of the filament through the small hole in the clip.

4. As shown in the closeup photo, carefully use a lighter to heat the very tip of the filament until it melts and forms a small, rounded bulb. This creates a secure stopper that prevents the filament from slipping out.

5. Repeat for the other side, snap the clips into place, and you are good to go!

Print Settings

• Material: PETG, ABS, or ASA (PLA can work, but PETG offers better clip flexibility)

• Infill: 15% - 20%

• Supports: No supports needed