If you mess with electronics long enough, you begin to have a collection of burnt-out soldering irons in need of replacement tips.
Instead of replacing the tip, grab a regular razor blade, and build yourself what I refer to as a Plasti-Cutter. Simply unscrew the retainer screw, remove the soldering tip, thread the screw through a razor blade, and screw it back into the hole.
Plug it in, let it warm up, and start slicing through plastic as if it were butter.
Just be careful with it. You’ve now created a tool capable of cutting yourself and burning your house down.
NEVER WALK AWAY FROM A PLUGGED-IN PLASTI-CUTTER OR SOLDERING IRON.