Hold the edge of your GS (Screw driver) with your left hand onto the lid of the can right by the edge of the lid. Then administer a sharp blow to the top of the GS with your right hand. Works every time, been doing it that way for thirty years. The person who showed me the way had been doing it that way for years previously. Never had a problem with metal flakes.
I don't think that any metal particals that you might introduce into the oil will be anything to worry about. The filters will catch them anyway.
Some of the guys I work with hold the can with the left hand and then stab the can lid with the screw driver
Rgds Dr I