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CoroMill 390 is your “go to” versatile tool that can mill a wide variety of component features from diverse materials, and utilizing an extensive selection of inserts can produce clean corner radii and remove material from various cutting depths. CoroMill 390 can mill almost any shape required.


High performance milling cutters that can perform many different operations have numerous benefits to a shop including fewer tool changes, shorter cycle times and reduced tool inventory. Whether your priority is an optimized process with close precision demands or a mixed production capacity with a focus on delivering value in a wide range of operations and materials, CoroMill 390 gets the job done.

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  • CoroMill 390 covers many applications with a large, versatile program that includes versions for shoulder milling and long edge milling
  • Cutters generate a 90-degree shoulder
  • Ideal for ramping and helical interpolation
View CoroMill 390 Products
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  • Features light-cutting insert geometries and high-performance grades
  • Designed for low-cutting forces and vibration-free machining for secure milling in all materials
  • The popular high-performance steel milling grade material, GC1130, is a perfect fit for the versatile CoroMill 390
View CoroMill 390 Inserts
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  • New cutter bodies offer better heat resistance
  • Choose between L, M or H pitch, of which parts of the assortment have been optimized with differential pitch for vibration-prone application
  • Internal coolant system available on most CoroMill 390 cutters cools the cutting process and flushes chips to avoid jamming
View CoroMill 390 Cutter Bodies


Pocket Milling

Challenge: Efficient and secure opening of cavities.

Solution: Using helical interpolation and linear ramping to create holes from a solid workpiece requires strong insert face geometry. CoroMill 390 inserts are designed to withstand stresses caused by steep ramping or demanding interpolation, providing a low-vibration process with even tool life.

Slot Milling

Challenge: Chip evacuation and vibration.

Solution: Insert geometries designed for ideal chip formation and evacuation. When milling with large engagements, vibration often causes rapid tool wear. The light-cutting inserts of CoroMill 390, combined with cutters with optimized differential pitch, offer a low-vibration milling process.

Face Milling / Key Slot Milling

Challenge: Metal removal rate and surface finish.

Solution: Durable CoroMill 390 inserts are capable of high cutting parameters. -L geometries designed for milling with low-cutting forces are appropriate for facing surfaces with a shiny finish and close tolerances.

Shoulder Milling

Challenge: Precise contours without steps in repeated shoulder milling.

Solution: Close-tolerance inserts and an exact insert position secure shoulders without steps. The smooth cutting action of CoroMill 390 limits radial cutting forces that provides machining with minimal bending and good wall perpendicularity.


For more info about CoroMill® 390 call 1-800-323-TOOL (8665) to speak with a Steiner metalworking representative.