Indexable Milling

Indexable milling uses a cutter body, either a shank-type end mill or an arbor-mounted shell/face mill fitted with replaceable carbide inserts secured in precision pockets.

When an insert's cutting edge becomes worn, it is either rotated to expose a fresh edge (indexed) or swapped for a new insert, without removing the cutter body from the machine.

This makes indexable milling highly economical and efficient, particularly for larger diameter tools and high-volume production work.

Some top advantages of indexable milling over solid carbide tooling include;

• Lower cost per edge - insert replacement is far cheaper than replacing an entire solid tool at larger diameters

• Fast changeover - inserts can be swapped at the machine without disturbing the setup

• Flexibility - different insert grades can be used in the same body to suit different materials or operations

• Scalability - indexable bodies are available in much larger diameters than solid carbide tools, up to 400mm and beyond

• Reduced downtime - no tool regrinding or resetting required; simply index or replace the insert.

Solid carbide cutting tools remain preferable for smaller diameters (typically under 12–16mm) and precision finishing where runout and edge sharpness are critical.

Our indexable milling range covers all the major milling operations:

• Face milling - producing flat, high-quality surfaces across the top of a workpiece

• Square shoulder milling - creating true 90° walls and steps in a single pass

• Profile milling - following 2D and 3D contours using round insert (ball nose style) cutters

• Slot milling - cutting full-width grooves and keyways

• High feed milling - extremely high feed rates with shallow depths of cut for rapid material removal

• T-slot milling - machining T-slots in machine tables and fixtures

• Chamfer milling - applying bevels and chamfers to component edges

• Bore milling - interpolating to produce accurate bores without a dedicated boring tool

• Helical milling - helical interpolation for producing circular features and thread milling

• Indexable milling heads - modular heads for use with quick-change systems.

• Face milling cutters - have insert geometry angled to cut primarily on the face, producing excellent flat surface finishes at high feed rates. However, the approach angle means they cannot produce a true 90° shoulder in a single pass

• Square shoulder milling cutters - are designed with inserts positioned to cut both the face and the side wall simultaneously, producing a true 90° step. They are the correct choice wherever a square shoulder, step, or pocket wall is required.

High feed milling uses a very small depth of cut (typically 0.5 to 2mm) combined with an extremely high feed rate per tooth (sometimes 10× that of conventional milling).

The shallow, near-axial cutting forces are directed back into the spindle rather than sideways, which in turn:

• Minimises deflection and vibration, even on long-reach or weakly-supported workpieces

• Allows very aggressive material removal rates on CNC machining centres

• Extends tool life by reducing radial cutting forces on the cutter body and inserts

• Makes it ideal for roughing deep pockets, curved surfaces, and difficult-to-machine materials.

High feed milling is a roughing strategy - finish passes with a different tool are typically still required.

Indexable milling insert type is matched to the cutter body - you cannot mix insert types between different bodies.

Common insert designations found within our range include:

• APKT / APMT - positive-rake square inserts, widely used in shoulder & face milling making them excellent for aluminium & steels

• SDMT - double-sided square insert with positive cutting geometry making it highly economical with multiple cutting edges

• RDKW / RCKT / RCMW - these are round inserts for profile milling, providing the strongest possible edge and smooth contouring

• SEET / SEKN / SEKR - square inserts for face and shoulder milling applications

• PNEG / HNEX - pentagon & hexagonal shaped inserts offering many cutting edges for face milling economy

• XPHT / ZPHT / MPHT - high-feed milling inserts with a wiper geometry for high productivity

• LNKT - rectangular inserts for slot & shoulder milling

• WPGT - trigon-style inserts for versatile shoulder and profile work

• ZOHX / ROHX - specialist round inserts for profile and 3D surface milling

Always check the product listing to confirm the insert type required for a specific cutter body!

Each indexable insert has multiple cutting edges and once one edge wears out, the insert is rotated around (indexed) to present a fresh cutting edge.

The number of usable edges directly affects the cost per edge:

• A single-sided insert with 4 corners gives 4 usable edges

• A double-sided insert with 4 corners per side gives 8 usable edges

• Round inserts (RCKT, RDKW) effectively have a continuous cutting edge and can be rotated slightly for fresh engagement.

More usable edges per insert = lower cost per edge = better economy over the life of the tool!

The spiggot (also known as the bore or arbor hole) is the central hole through a shell or face mill body that locates it onto the arbor or adaptor.

Common spiggot sizes we stock include 16mm, 22mm, 27mm, 32mm, and 40mm.

You must match the spiggot size to your arbor or face mill adaptor as using the wrong size will prevent the cutter from mounting correctly. If you're unsure of your machine's arbor size, check your toolholder specification or contact us.

We stock indexable milling cutters from 12mm up to 400mm in diameter, covering:

• Small diameter shank-type end mills (12–32mm) for profiling, shouldering, and high-feed work

• Mid-range arbor cutters (40–125mm) for shouldering, face milling, and slotting

• Large diameter face mills (160–400mm) for high-productivity face milling on large machining centres and horizontal borers

Use our diameter filter to quickly narrow down the options for your application!

Indexable milling heads are modular cutting heads that connect to quick-change systems, allowing rapid tool changes without removing the full tool assembly.

They are particularly useful in:

• High-volume production where tool change time must be minimised

• Situations where multiple operations use the same toolholder but different cutting heads

• Applications where precise tool length repeat accuracy is essential between changes