Originally Posted by CR94
You can do it with a hacksaw with minimal contamination of the media with metal particles, IF you cut only most of the way through, then break off the base by striking the seam sharply to break it off the can.
That's a slow method, though. If doing more than a few, the price of a more efficient dedicated filter cutter might be justified.
I never had luck with a hack saw, I always got stuff in the filter, and does take forever. I used a dremel, but was horrible for contamination, and would go through cutting wheels like crazy.
Don't cheap out on one though, I bought the cheapest one I could find on e-bay ($35-40) and it works OK, but wish I had just spent another $20 to get a good one (Longacre or Lisle).