This Extruder Visualizer is based on the “Josef Slurping Spaghetti” graphic found on empty Prusament spools. The two-tone Josef component slides onto the extruder motor. The spool is made in two segments so no supports are necessary and everything prints fast. The “Filament” slips over the “Spool Front” and then the two spool halves are held together with a small dab of glue. It is important that the "Filament" component does not get glued to the spool and can rotate freely. The Josef component can be slid onto the motor and the loose end of the filament inserts into the hole in the Josef component. You may have to heat up the loose end of the filament and form it into shape so it curves into Josef's mouth correctly. The last thing to determine is how to attach the spool to the extruder motor. I used a 6mm diameter x 1.7mm thick magnet that I got in an assortment from Amazon. If you'd like to use a different attachment method, let me know and I can modify the “Spool Back” file to suit your solution.
Since the extruder motor can get hot, it is recommended to print these parts out of PETG, ABS, ASA or another relatively high-temperature material.
There are other extruder visualizers that riff off of this same basic concept:
Stabilized Prusament Spool Motor Visualizer
Josef Prusa Stepper Motor Indicator
The author marked this model as their own original creation.