i need to do 300 holes on a 5/15" steel plate ( over girders on a bridge). The diameter of these holes is 1 1/2". I'd like to use theequipment that i have; the combohammer TE-56 from Hilti. This equipment is design to work drilling holes on concrete, but i think I could used it for drill over this steel plate (ASTM -A36) too. The speed of this equipment is 485 RPM. What do you think?