13-03-2022, 10:29 AM
Re your failed holes, drill from the other side of the plate on the same hole centres; the work hardening will only be on the drilled surface in my experience. As all have said, you'll be wasting your time and effort unless the drill is sharp. Use a cutting fluid NOT motor oil. Maintain constant pressure when drilling. The moment the drill 'rides' on stainless, the Nickel content will work harden it.