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Trouble Shooting

ProblemPossible Reasons Actions Insert breakageSplintering ofcutting edgeVibrations/ChatterChip jamEdge built-upSticking chipsComb crackingsTransverse cracksWear notchFormation of burrsWorkpiecebreakageSurface finishRecutting
• Earlier insert change• Remachining of insert/insert exchange • Correct insert mounting • Select tougher cutting grade • Select geometry with higher stability• Reduce chip thickness• Improve positioning of mill andworkpiece• Horizontal spindle: upward milling • Vertical spindle: remove chips• Select tougher cutting grade• Select geometry with higher stability • Improve positioning of mill andworkpiece• Avoid• Improve• Improve positioning of mill andworkpiece• Use mill with wider tooth pitch• Select mill with unequal tooth pitch• Change speed (Resonance!) • Select rather positive geometry • Increase feed per tooth • Cantilever length as short as possible• Use mill with wider tooth pitch• Use mill with κ = 45• Change chip thickness• Increase cutting speed• Select coated carbide• Increase cutting speed• Select coated carbide • Improve positioning mill – workpiece• Reduce cutting speed• Reduce feed per tooth• Select tougher grade• Select grade with higher wear resistance• Select smaller approach angle• Select grade with higher wear resistance• Climb milling • Reduce cutting speed• Select sharper cutting edges• Select rather positive geometry• Select smaller approach angle• Select sharper cutting edges• Select rather positive geometry • Select smaller approach angle • Change positioning mill – workpiece • Climb milling • Before milling, chamfering of tool exit• Use insert with face chamfer• Plane running errors eliminate/to reduce • Reduce • Use of wiper insert • Correct mounting of mill • Cleaning of cutting area • Re-machining of spindle nose/head• Reduce chip thickness• Use smaller mill• Select smaller approach angle • Earlier insert change • Extensive wear• Wrong insert position • Wrong insert mounting • Too brittle cutting grade • Unsuitable cutting edge geometry • Cutting edge overload• Unfavourable positioning of mill and workpiece• ”Curled” chips• Too brittle cutting grade• Unsuitable cutting edge geometry • Unfavourable positioning of mill andworkpiece• Vibrations/Chatter• Unfavourable rigidity of machine, workpiece, clamping, tool• Unfavourable positioning of mill and workpiece• Too many teeth in cut • Unfavourable tooth contact• Unfavourable cutting edge geometry• Cantilever length too long• Chip space too small• Temperature of chip – cutting edge contact zone too low• Temperature of chip – cutting edgecontact zone too low• Insufficient resistance to heat alternations• Insufficient resistance to heat alternations• Hard marginal zone• Extensive wear• Edge sharpness too low• Cutting force too high • Unfavourable direction of cutting force• Edge sharpness too low• Cutting force too high • Unfavourable direction of cutting force• Brittle workpiece material• Cutting edge with corner radius• Cutting edge with corner radius • Feed per rev. too high• Tumbing error of mill on spindle• Tumbing error of mill on spindle Extensiveflank wear

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