The old spin-on oil filters contain lots of oil even after allowing them to drain via gravity. Crushing them expels most of the oil allowing the resulting metal puck to be picked up by the standard curb recycling crews; just one less thing requiring special trips for proper disposal.
Components were sourced at the local scrap yard. All it takes are some type of cylinder and plate steel.
Cut the cylinder to height. Make a base for the cylinder with the plate steel. Weld in some stand-offs on the bottom of the base before attaching the cylinder body. The object is to give the oil a gap to escape from the filter as it is crushed.
Make the crushing piston. I stacked two sections of plate steel on top of each other for added rigidity.
Since this isn't a production use tool I didn't even bother with providing a way to drain the oil. I'm only going to be crushing two or three filters at a time. When there's enough oil in the bottom of the crusher it gets dumped into recycling jugs. When done with the crusher it gets placed in an oil collection pan upside down to drain fully.