A long, heavy engineer’s screwdriver....... The flat blade wants tapping (with a hammer!) against the base of the filter to create a purchase point. You can then whack it at a tangent to free off a reluctant filter.
A rubber strap wrench is versatile for many tasks if access is possible. For a limited workshop I'd (I already have with the small size to the in-laws for jar tops) go for one of these; https://www.amazon.co.uk/Silverline...45&hvtargid=pla-422817795108&psc=1&th=1&psc=1
I have one of these. https://www.ebay.co.uk/itm/OIL-FILT...420917?hash=item3fb0479535:g:rOMAAOSwwtdb3OcG but the filter was so tight this would just spin, even with upward force ( car jack) and so I borrowed this. Fantastic kit, if you can access the filter and have room to turn it. https://www.ebay.co.uk/itm/Adjustab...713907?hash=item52282333b3:g:5RIAAOSweOldCgGE
A 3 legged mangle is no better than the previously advised "bash a screwdriver through it tangentially" and he could no doubt have saved himself the expense. Retail therapy is a strange thing. Advice, who needs advice?
I never said ‘through it’....... plenty of bodgers do, however. The base of a filter is its strongest point. Create a small ledge in the rim and you can create a leverage point to break the seal by using a hammer (lump!) and long screwdriver to get knuckles clear and a near 90 degree lever. Mangling them creates a hazard to hands and also makes it more difficult if you eventually need to use a proper tool for the job.
