We are currently drilling/tapping aluminum with combination drill/tap bits. Spindle speed for drilling is 7400 rpm with feed of 1876 mm/min, tapping speed is 2000 rpm - 5 mm tap. Is it safe to go any faster than this? Max spindle speed is 15000.

I am trying to shave precious seconds off a cycle time, can someone tell me if the following is worth the trouble. When going from one hole to the next, it goes straight up, over to the next, straight down. What if I changed this to make an arc in the vertical plane so that the z axis doesn't have to slow down before the horizontal starts moving. Would this make any difference?

Joe