How to choose the right cutting tools for CNC milling machines?

I. Core Principles for Tool Selection

Applicability first ‌ : The cutting tool must be capable of achieving the processing objective (such as removing allowance and ensuring accuracy), and be compatible with the workpiece and the machine tool to avoid collision.

Rigidity and stability ‌ : Give priority to short overhang and large-diameter tools to reduce vibration and ensure processing safety.

Economical and efficient ‌ : balancing tool cost, lifespan and processing efficiency, indexable tools are suitable for large quantities, and integral tools are suitable for complex parts.

Ⅱ. Selection Steps and Key Factors

Step 1: Clarify the processing requirements ‌

Processing stage ‌ : Rough machining uses tools with good rigidity but low precision (such as two-edge end mills); Durable and high-precision cutting tools (such as four-edge end mills) for semi-finishing and finishing.

Machining area ‌ : ball-end mills for complex cavities; Keyway milling cutter for closed slots; Face milling cutters for large-area planes.

Step 2: Match the workpiece material ‌

Aluminum alloy/copper alloy ‌ : Select high-speed steel (HSS) or diamond tools, with no more than 4 teeth to prevent built-up edge.

Stainless steel/titanium alloy ‌ : Select coated cemented carbide or cobalt-containing high-speed steel, and pay attention to anti-adhesion.

Hardened steel ‌ : choose cubic boron nitride (CBN) or ceramic tools.

Step 3: Adapt the machine tool performance ‌

Spindle compatibility ‌ : ensure that the tool shank diameter (e.g. 20mm) and cutting edge diameter match the machine tool.

Power matching ‌ : Select tools and parameters based on the machine tool power (e.g. 20hp) to achieve efficient cutting.

Step 4: Optimize tool parameters ‌

Geometric parameter ‌ : the number of edges affects chip removal and vibration (two edges for soft materials and four edges for hard materials); Diameter and overhang affect rigidity.

Cutting parameters ‌ : Adjust the feed rate and cutting depth according to the precision requirements.

Ⅲ. Quick Check of Tool Types (Common Scenarios)

Processing scene	Recommended knives	Core features
Planar	End mills, face mills	It has strong versatility, and the end face cutting edge is a secondary cutting edge
Curved Surface	Ball nose end mill	The hemispherical tip reduces vibration and improves smoothness
Slotting	Keyseat cutter	The helix Angle is small, the groove is deep, and chip removal is easy
Spot facing work	Drill bit (rough), reamer (fine)	Drill bits for drilling and reamers for precise reaming
Thread machining	Thread milling cutter	Integral type or insert type, processing internal/external threads