Posted by Joe Lorenzino on Monday, January 26, 2004 at 11:00PM :
In Reply to: Ask a waterjet shop........... posted by Jack Cain on Monday, January 26, 2004 at 8:52PM :
this might also work. At work, we drill holes through hardened steel using a resharpened Carbide Masonry Bit. If you grind them to a proper drill profile, but with a much flatter center angle, and turn them really slow with plenty of coolant, they will drill through springs, grader blades,etc. I agree with Marty that using a plasma on the planer knives could be hazardous due to the "breakage" potential. Even if the temper is not lost from the edge of the blades, the heat effected zone near the plasma cut could cause the blades to crack around the mounting holes. Using a carbide drill to make new holes should not affect the temper of the blades, if done properly. It might be worth a try. J.V.L.