I have to cut a .250" wide by .125 deep by 8" long slot down the center of 6 pieces of .500" square 4140. Now I was thinking about using a HSS woodruff cutter, but I don't what kind of feed and speed to use. Or would a .25" carbide EM do the job. I'm thinking the EM will give out before I get all 6 pieces done. Any thoughts?