Machining Applications Views: 12

Tips for surface finish when countersinking: 1) Sharp tool - dull tools leave rough surfaces; re-sharpen or replace promptly; new or freshly sharpened tools give the best finish; 2) Good parameters - moderately higher speed (but not for stainless), smaller feed; thin chips give a smoother finish; generally feed 0.03-0.1mm/rev; 3) Cutting fluid - flood cooling and lubrication reduce friction and welding: smoother finish; semi-synthetic for aluminum, EP emulsion for stainless; 4) Final light pass - after reaching size, run one idle revolution (spindle turning with no feed); the effect is obvious - finish improves 1-2 grades; 5) Low runout - runout leaves tool marks; check after clamping, keep under 0.02mm; use ER collets, not drill chucks; 6) Short overhang - long overhang is weak, vibrates and leaves chatter marks; keep overhang under 3x shank diameter; 7) Secure workpiece - movement hurts finish; clamp firmly, support thin walls; 8) Coated tools - TiAlN has low friction and resists welding: smoother finish, especially on stainless and aluminum; 9) Avoid built-up edge - BUE roughens the surface; change speed (avoid the BUE range), use cutting fluid and sharp tools; 10) Material match - use the right grade for the material; no standard HSS on stainless (welding), no carbide on soft materials (chipping). Finish reference: 1) Ra3.2 - ordinary chamfering, achievable with normal parameters; 2) Ra1.6 - fine chamfering: small feed + final light pass + sharp tool; 3) Ra0.8 - mirror chamfering: ultra-fine-grain carbide + high speed + small feed + final pass + polishing. Follow these tips and the finish will improve visibly. Ask our technical team to optimize parameters.