Machining Applications Views: 22

Spot drill parameters follow the same principles as regular countersinks: low speed, generous feed, smooth cutting, clean finish. Reference parameters (cobalt HSS spot drills): carbon/alloy steel - 800-1500rpm, feed 0.1-0.2mm/rev; stainless steel - 400-800rpm, 0.05-0.1mm/rev; aluminum/copper - 1500-3000rpm, 0.15-0.3mm/rev. Small sizes (under 6mm) can run faster; large sizes (over 20mm) need lower speeds. On slopes, feed slightly slower than on straight holes to prevent slipping.