Having trouble removing a broken caster from a Henry Vacuum, (or as they're commonly known, at least here in the UK, Henry Hoovers)?
Try this easy method using a regular claw hammer. Either side of the claw grips around the caster's metal shaft. You have to put all your weight on a foot to hold it down to the floor.
The trick is to give the hammer a sudden jolt rather than exerting a constant/ steady pressure.