Machining Applications Views: 15

Yes, countersinks can handle interrupted cutting, but impact is heavy - protect the tool. What is interrupted cutting: the tool alternately contacts and leaves the workpiece, e.g.: 1) chamfers at slots, holes, notches - the tool leaves at the slot and contacts at solid; 2) thin-wall and skeleton parts with many holes and slots; 3) castings and forgings with scale and uneven surfaces; 4) cross-hole chamfers - interrupted by intersecting holes. Hazards: 1) heavy impact - repeated entry/exit chips edges; 2) thermal shock - repeated heating/cooling causes heat cracks and fast wear; 3) faster wear - life is 30%-50% shorter than continuous cutting; 4) poor finish - impact leaves chatter marks. Notes: 1) lower speed - reduce impact and thermal shock; generally 30%-50% below continuous; 2) smaller feed - 20%-30% below continuous; 3) tough grades - cobalt HSS (HSS-E) is tougher than carbide and resists chipping; if carbide, choose tough grades (e.g. YG type), not hard-brittle ones; 4) edge strengthening - hone or chamfer the edge to prevent chipping; 5) avoid dry cutting - generous fluid reduces thermal shock, but do not suddenly apply cold fluid to a very hot tool (heat cracks); apply from the start; 6) smaller entry angle - reduces impact; 7) single-flute tools - less force and impact, better for interrupted cutting; 8) regular checks - interrupted cutting chips tools; inspect periodically and replace promptly; 9) first-piece trial before the batch. Reference parameters (cobalt HSS): 1) carbon steel interrupted - 500-1000rpm, feed 0.05-0.1mm/rev; 2) stainless interrupted - 300-600rpm, feed 0.03-0.08mm/rev; 3) cast iron interrupted - 400-800rpm, feed 0.05-0.1mm/rev. Interrupted cutting mainly demands tool protection - these methods extend life effectively. Ask our technical team.