Using the bottle cutter
Using the cutter is quite easy.
Put it into a vice with the "finger" in the back. Then insert the left side of the bottle into the finger and under the right roller bearings. You can start pulling, while keeping the bottle vertical and gently pressed into the notch.
After a few centimeters, the ribbon will become nice and consistent (no dent and good height). You can sharpen the tip, this will be used for starting the pullStruding !
Take your time, pull evenly, and go to the top of the bottle, while a finger in the bottle neck helps a lot to keep the bottle in place.
Now cut the end, and starting from this side, roll the ribbon in a nice flat disc shape and insert the tip (previously sharpened) into the spool holder (The top of the bottle is in the center of disc).
If properly done the ribbon will be very consistant and with a width of 8.5mm
You are ready to make the filament !