HSS End Mills – M2, M35 & M42 High Speed Steel Milling Cutters

HSS end mills are milling cutters manufactured from high speed steel. Their toughness makes them suitable for general machining, conventional or manual milling machines, and selected CNC operations.

M2 is a common general-purpose HSS grade, while M35 and M42 contain cobalt to provide greater hot hardness and wear resistance for more demanding cutting conditions.

We offer metric and inch HSS milling cutters with different flute counts, end geometries, lengths and surface treatments. Standard specifications cover common requirements, while we manufacture non-standard HSS end mill cutters according to drawings or dimensional specifications.

Specification Options

Ball nose, corner radius and different flute-count designs are available options within the HSS end mill range. Select the geometry according to the machining operation and workpiece material.

Applications and Selection

Choosing M2, M35 or M42 HSS

The HSS grade should match the workpiece material, cutting temperature and machining conditions.

M2 HSS is a common general-purpose choice with good toughness and cost efficiency for general milling of carbon steel, aluminum, copper and plastics under suitable conditions.

M35 HSS contains approximately 5% cobalt. Compared with M2, it offers better hot hardness and wear resistance and is commonly considered for stainless steel, alloy steel and applications that generate more cutting heat.

M42 HSS contains approximately 8% cobalt and provides greater hot hardness and wear resistance than M2 or M35. It can be considered when cutting-edge wear and heat resistance are more demanding.

For high-speed machining, highly abrasive materials or hardened workpieces, solid carbide may provide better rigidity, wear resistance and cutting-speed capability.

Choosing the Flute Count

2 Flutes provide more chip space and are commonly used for slotting, aluminum, copper, plastics and other applications where chip evacuation is important.

3 Flutes provide a balance between chip clearance and cutting-edge count and can suit slotting, semi-finishing and selected non-ferrous or stainless steel applications.

4 Flutes provide more cutting edges and a stronger core, making them a common choice for steel, stainless steel, side milling, profiling and general-purpose milling.

6 Flutes provide additional cutting edges and are mainly suited to stable side-milling and finishing conditions where chip space is less critical.

Consider flute count together with cutter diameter, engagement, machine rigidity, tool overhang and chip evacuation.

Workpiece Selection

Steel: M2 suits many general-purpose applications. Choose M35 or M42 when the application requires greater hot hardness or wear resistance

Stainless Steel: M35 or M42 is generally a better starting choice than standard M2. Choose a suitable coating according to the machining conditions.

Aluminum: Two- or three-flute designs with sufficient chip space are commonly preferred. Bright or suitable uncoated finishes can help maintain smooth chip flow.

Copper and Copper Alloys: A suitable flute geometry and sharp cutting edge allow HSS end mills to machine these materials effectively.

Plastics: HSS provides a sharp cutting edge for plastics, nylon, POM, acrylic and similar materials. Chip evacuation and heat generation should be considered.

Cast Iron: HSS works for selected applications under suitable cutting conditions. For continuous high-volume machining with significant abrasive wear, carbide may provide better wear resistance.

Key Features

M2, M35 and M42 Material Options

M2, M35 and M42 grades allow selection according to workpiece material, cutting heat, wear requirements and budget.

Metric and Inch Sizes

Metric and inch specifications are available. We supply standard dimensions according to availability and manufacture special diameters, shanks and lengths to order.

Multiple Flute and End Geometries

Available options include 2, 3, 4 and 6 flutes, together with square, flat, ball nose and corner radius end geometries.

Coated and Uncoated Options

We offer bright or uncoated HSS for suitable applications. Choose TiN, TiCN, TiAlN or AlTiN coatings according to the workpiece and cutting conditions.

Standard and Custom Manufacturing

Standard specifications cover common requirements, while we produce non-standard HSS end mills according to customer drawings or dimensions.

Custom Manufacturing

For non-standard requirements, we can manufacture custom HSS end mills according to your drawing or specification.

Custom options may include:

• Cutting diameter
• Flute length
• Overall length
• Shank diameter
• Flute count
• End geometry
• Corner radius
• Metric or inch dimensions
• Bright or coated finish
• Special length combinations

For custom tools, a drawing is recommended when the cutter includes non-standard diameters, shanks, flute lengths, overall lengths, radii or other special geometry.

FAQ

What is the difference between M2, M35 and M42 HSS end mills?

M2 is a general-purpose high speed steel with good toughness and cost efficiency. M35 contains approximately 5% cobalt for improved hot hardness and wear resistance. M42 contains approximately 8% cobalt and provides still greater hot hardness and wear resistance for more demanding cutting conditions.

When should I choose an HSS end mill instead of a carbide end mill?

HSS can be a practical choice when toughness, cost, lower cutting speed, conventional machine use or resistance to chipping is important. Carbide is generally preferred when the application requires higher cutting speeds, greater rigidity or better wear resistance on abrasive or harder materials.

Which flute count should I choose for an HSS end mill?

Two flutes provide more chip space, while four flutes provide more cutting edges and a stronger core. Three flutes provide a balance between the two, while six flutes are mainly suited to stable side-milling or finishing conditions.

Are metric and inch HSS end mill sizes available?

Yes. Metric and inch HSS end mills are available in standard specifications, while non-standard diameters, lengths and shank sizes can also be evaluated for custom production.

Which coatings are available for HSS end mills?

Available options include bright or uncoated HSS, TiN, TiCN, TiAlN and AlTiN. The coating should be selected according to the workpiece material and machining conditions.

Can you manufacture custom HSS end mills from a drawing?

Yes. We can evaluate custom production from your drawing or dimensional specification. Please provide the cutting diameter, flute length, overall length, shank diameter, flute count, end geometry, coating requirement and workpiece information when available.

Are cobalt HSS end mills available?

Yes. M35 and M42 contain cobalt and provide greater hot hardness and wear resistance than standard M2. We stock selected standard sizes and can manufacture non-standard specifications to order.

Send Your HSS End Mill Requirement

For a quotation, please send the required HSS grade, cutting diameter, flute count, end type, coating, workpiece material and quantity to sales@cutterbest.com.

For a custom HSS end mill, please also provide the flute length, overall length, shank diameter, corner radius or other special dimensions. Please send a drawing for non-standard tools so we can review the specification before production.