is this a BAD idea (freeze water in caliper to POP piston)?

I know this was mentioned and I'm not rying to be funny repeating it, but wear goggles and keep your hands away from the pinch point if you are using the air method. My friend thanked me many times after I made him wear goggles while unsticking a stuck piston. The thing exploded brake fluid all over his face. It sounded like a firecracker going off.

i used air on mine last night. and u are right . 1 of my zx9 pistons flew across the room. :woohoo: on the up side . u cant amagine all of the things u can find under your bench when u get down there.lol.

ice will expand in all directions and might split the caliper
try steam , put some water in it, seal it put it in a coffee can put some rags over it, pop it in the oven at about 300
give it a while, when the water boils somethings gona give, unless it leaks, then bake some cookies while it cools off

I've always used the air on calipers. Granted, being a mech I have access to 180psi, I always put a thin wooden block and cover with a rag as I apply air pressure. Never had one get away or spray me. Good luck...