I use a hacksaw. Others have reported a can opener works. For all the more filters I cut open, I can't see buying a special tool. Count on getting some links to special tools.
hack saw, can opener, and tailpipe cutter. the tailpipe cutter is what i make to use the initial cuts, then i do the rest with the can opener. and i think i just used the hack saw to cut out filter media. i forget since i havent done this in awhile
Before I cut a filter cutter, I opened afew with Vise Grips. I pealed the crimped edge back from the base, gradually working around the base. Takes a few minutes.
Some cost less than this one and others cost more. The important thing to some inspections is to keep cutting contamination out of the filter. With a hack saw and other methods, that becomes difficult.
