Super home brew penetrating oil, 1000x better than WD40.
- 50% acetone
- 45% brake fuild
- 5% ATF

Do NOT get it near paint though and as with all penetrating oils, repeated application and give it time to work.
Acetone evaporates after time so only make small batches as needed.

Then BFH, if in doubt give it a clout ! if that doesn't work then get a bigger one !