MH(350) 4 flute long neck carbide square end mill with 0.3–0.4μm ultra-fine carbide and AlCrN PVD coating for deep grooves, pockets and restricted machining of stainless steel, titanium and hardened steel up to 52 HRC.
The MH(350) 4 flute long neck end mill is designed for milling deep and restricted features where a standard-length cutter cannot provide sufficient clearance or reach.
Its long neck configuration provides additional clearance behind the cutting section, while the 0.3–0.4μm ultra-fine carbide substrate, AlCrN PVD coating and dedicated cutting geometry support stable machining in stainless steel, copper, titanium alloys and hardened steel up to 52 HRC.
The tool is suitable for high-speed, dry and coolant-assisted machining when the tool overhang and cutting conditions are properly controlled.
Key Product Features
Where the Long Neck Design Makes a Difference
The MH(350) is intended for machining situations where tool access becomes more important than simply increasing cutting length.
Deep Grooves
The extended neck provides clearance for grooves that require deeper tool access than a conventional square end mill.
Recessed Pockets
Suitable for recessed pockets where the tool body or holder may interfere with the workpiece.
Deep Cavities
The long neck configuration allows the cutting edge to reach deeper cavity features while maintaining a relatively compact flute section.
Narrow Machining Areas
Useful when surrounding walls or shoulders restrict access to the cutting area.
Mold and Precision Components
Suitable for deep ribs, inserts, recessed features and other precision components requiring additional tool reach.
Long-neck square end mills are commonly used for deep grooves, recessed pockets, flat-bottom cavities and restricted machining areas; excessive neck length or tool overhang, however, can reduce rigidity and increase vibration.
Long Neck Without Unnecessary Overhang
For deep machining, reaching the feature is only part of the problem. Tool rigidity also affects surface finish, dimensional accuracy and tool life.
Use the Shortest Practical Reach
Choose an effective length that reaches the feature without creating unnecessary unsupported tool length.
Control Tool Overhang
Longer projection increases the risk of vibration and deflection, especially when machining hard materials.
Match the Neck to the Feature
The neck should provide enough clearance from the workpiece while maintaining sufficient tool strength.
Keep the Cutting Load Controlled
For deep machining, lighter radial engagement and suitable axial depth can help maintain stability when the effective length is long.
This selection principle is also reflected in industrial long-neck tool catalogs, which separate flute length, effective length, neck diameter and overall length as key dimensions.
Material Applications
Stainless Steel
The AlCrN coating helps reduce adhesion and built-up edge when the long-neck tool is used for deep or restricted stainless steel machining.
Copper
Suitable for deep pockets, grooves and precision features in copper components.
Titanium Alloys
The MH(350) can be used for difficult titanium applications where heat generation, tool wear and tool stability must be carefully controlled.
Hardened Steel
Suitable for hardened steel up to 52 HRC under appropriate machining conditions.
Material & Application Guide
| Workpiece | Recommended Use | Main Consideration |
| Stainless Steel | Deep grooves and recessed features | Adhesion and heat |
| Copper | Deep pockets and precision features | Cutting stability |
| Titanium Alloy | Restricted and deep machining | Heat and tool wear |
| Hardened Steel ≤52 HRC | Deep mold and die features | Rigidity and cutting load |
Actual performance depends on material grade, hardness, tool diameter, effective length, tool overhang, machine rigidity and cutting conditions.
MH(350) Tool Technology
0.3–0.4μm Ultra-Fine Carbide
The ultra-fine carbide substrate is selected for demanding applications requiring high hardness, wear resistance and stable cutting-edge performance.
AlCrN PVD Coating
The AlCrN coating provides high-temperature oxidation resistance and thermal stability for demanding cutting conditions.
Dedicated Cutting Geometry
The MH(350) uses a specialized geometry developed for high-speed machining rather than a basic long-neck configuration.
Anti-Adhesion Performance
The coating and tool geometry help reduce material adhesion, particularly when machining stainless steel.
Technical Specifications
| Parameter | Specification |
| Series | MH(350) |
| Tool Type | 4 Flute Long Neck Carbide Square End Mill |
| Flute Count | 4 |
| End Type | Square |
| Neck Design | Long Neck |
| Carbide Substrate | 0.3–0.4μm Ultra-Fine Grain Carbide |
| Coating | AlCrN PVD |
| Hardened Steel | Up to 52 HRC |
| Cutting Modes | High-Speed / Dry / Coolant-Assisted |
| Recommended Materials | Stainless Steel, Copper, Titanium Alloy, Hardened Steel |
Critical Dimensions for Long Neck Selection
For this type of cutter, diameter alone is not enough to determine whether the tool is suitable.
Important dimensions include:
How to Select the Right Long Neck End Mill
Start With Machining Depth
Measure the actual feature depth rather than selecting a tool based only on overall length.
Select the Cutting Diameter
Choose a diameter that fits the feature while providing sufficient cutting strength.
Check Effective Length
The effective length should provide the required reach with minimal unnecessary extension.
Check Neck Clearance
Make sure the reduced neck provides enough clearance from surrounding walls, ribs or shoulders.
Consider Tool Rigidity
The longer the unsupported section, the greater the sensitivity to vibration and deflection.
Cutting Conditions
The MH(350) is suitable for high-speed and dry machining, but long-neck applications require more careful parameter selection than standard-length tools.
Recommended cutting data can be provided for:
For deep machining, parameters should be adjusted according to tool diameter, effective length, workpiece material, hardness and tool overhang.
Custom Long Neck End Mills
When standard dimensions do not provide the required reach or clearance, JimmyTool can manufacture customized long-neck carbide end mills.
Custom Options
Frequently Asked Questions
What is a 4 flute long neck end mill used for?
It is designed for deep grooves, recessed pockets, deep cavities and restricted machining areas where a standard-length end mill may not provide enough clearance or reach.
Why use a long neck instead of simply using a longer flute?
A long-neck design can provide additional reach and clearance while keeping the actual cutting section relatively compact, helping avoid unnecessary cutting length.
Is the MH(350) suitable for deep cavity machining?
Yes. The long-neck configuration is intended for deep and recessed features, including mold and precision-component applications.
Can the MH(350) machine stainless steel?
Yes. Stainless steel is one of the recommended materials, particularly for deep and restricted machining applications where anti-adhesion performance is important.
Can it machine hardened steel?
Yes. The MH(350) is suitable for hardened steel up to 52 HRC under appropriate cutting conditions.
Can the MH(350) be used for dry machining?
Yes. It supports dry cutting as well as coolant-assisted machining, depending on the material and machining setup.
What is the most important factor when using a long-neck end mill?
Tool rigidity is critical. Effective length and overhang should be kept as short as the machining geometry allows to reduce vibration and deflection.
Can JimmyTool customize the long-neck configuration?
Yes. JimmyTool can customize the cutting diameter, effective length, neck dimensions, shank size, geometry and coating according to application requirements.
