Drill hard steel.
We have often managed to drill very hard steel by regrinding a masonry drill to the shape of a steel drill.. You will need a green grit stone to do the grinding, you will need to run the drill at low speed and use cutting compound. This technique is only suitable for one off jobs. For drilling many holes you will need to buy something expensive. If you need any more info please get in touch. 01609 773607 or firstname.lastname@example.org. We accept no responsibility for any problems you may incur by following this advice.