What Is Tnmg 160404? Dimensions, Applications, and Holder Compatibility

TNMG 160404 is a negative-rake, 60-degree triangular indexable turning insert with a nominal 0.4 mm nose radius. In the commonly used ISO designation, “TNMG” identifies the insert shape, clearance angle, tolerance class, and chipbreaker or hole configuration, while “160404” identifies the insert size and nose radius. Its typical nominal dimensions are approximately 9.525 mm inscribed circle, 4.76 mm thickness, and 0.4 mm nose radius, although exact catalog values and usable cutting edges can vary by manufacturer. I supply TNMG-compatible boring and turning tooling through KEUE CNC, with selection support based on the machine, workpiece material, holder, and cutting conditions.

You can find more information on our web, so please take a look.

TNMG 160404 Designation Explained

TNMG 160404 belongs to the ISO system for indexable carbide inserts. The first letter, “T,” indicates a triangular insert with an included angle of approximately 60 degrees. The second letter, “N,” indicates a nominal 0-degree clearance angle, so the insert is designed for negative-rake tooling and requires a rigid setup.

The third character, “M,” refers to the insert tolerance class commonly used for general-purpose machining. The fourth character, “G,” identifies the insert style, including its hole and chipbreaker-related configuration; the exact geometry should always be confirmed from the supplier drawing. The number “16” generally corresponds to the insert size, “04” indicates a nominal thickness near 4.76 mm, and the final “04” indicates a 0.4 mm nose radius.

Core Dimensions and Technical Specifications

For purchasing and holder matching, I recommend treating the following values as standard reference dimensions rather than assuming that every brand uses identical geometry. Chipbreakers, coating thickness, corner preparation, and edge treatment can change the cutting behavior even when the ISO code remains the same. Before production use, I verify the manufacturer’s technical drawing and the holder’s required insert specification.

The 0.4 mm nose radius is relatively suitable when I need a balance between accessibility and finish quality. A smaller radius can reduce cutting forces and improve access in narrow features, while a larger radius can support heavier cuts but may require more rigidity. These effects depend on workpiece material, feed rate, depth of cut, tool overhang, and machine condition.

What Does TNMG 160404 Do?

TNMG 160404 is used for material removal during turning and boring operations. Its triangular geometry provides three primary cutting corners when the insert is indexed correctly, which can help reduce tool-change frequency compared with a single-corner tool. Because it has a negative clearance design, it is generally selected for rigid toolholders, stable workholding, and machines capable of maintaining sufficient cutting force.

External Turning

In external turning, TNMG 160404 can be used for roughing, semi-finishing, and selected finishing operations. The actual suitability depends mainly on the insert grade and chipbreaker, not only on the insert code. For steel, stainless steel, cast iron, or non-ferrous materials, I match the carbide substrate and coating to the material instead of using one grade for every job.

Internal Turning and Boring

TNMG 160404 is also commonly considered for boring tools where the internal diameter is large enough to provide insert clearance. In a boring application, the holder size, bar stiffness, minimum bore diameter, and insert orientation are especially important. A long boring bar with excessive overhang can increase vibration, so I normally evaluate the complete boring-tool assembly rather than selecting the insert in isolation.

Applications and Material Options

Typical applications include machining carbon steel, alloy steel, stainless steel, cast iron, and selected non-ferrous metals. For general steel machining, a coated carbide grade with a suitable chipbreaker may provide a practical starting point. Stainless steel often requires a more positive cutting geometry or a grade designed to reduce built-up edge, while cast iron may require an edge and coating designed for abrasive interrupted cutting.

Link to KEUE CNC

Aluminum and other soft non-ferrous materials require additional caution. A standard negative TNMG geometry may not be the most efficient option when sharp edges and low cutting forces are priorities. For these materials, I may recommend comparing TNMG with a polished or positive insert geometry after reviewing the required surface finish and machine rigidity.

Holder Compatibility for TNMG 160404

TNMG 160404 must be installed in a holder designed for a TNMG-style negative triangular insert and the corresponding size designation. Common holder families may include external turning holders such as MTJNR or related negative-style configurations, as well as internal boring holders identified by the manufacturer as TNMG-compatible. However, the holder code varies by hand orientation, shank size, clamping method, and intended cutting direction.

For boring applications, I check four items before confirming compatibility: the insert shape, the insert size, the clamping system, and the minimum internal diameter. The holder must also provide the correct approach angle and sufficient clearance from the bore wall. A holder that accepts a triangular negative insert is not automatically compatible with every TNMG 160404 geometry, particularly when the hole form or chipbreaker profile differs.

Holder Selection Checklist

• Confirm that the holder specification explicitly supports TNMG inserts.
• Match the holder to the 1604 insert size rather than relying only on visual similarity.
• Verify right-hand or left-hand cutting direction and the required approach angle.
• Check the boring bar diameter, minimum bore size, and expected tool overhang.
• Confirm that the clamping screw, top clamp, seat, and locating surfaces are suitable for the insert.
• Review the manufacturer drawing when using a non-standard chipbreaker or coated insert.

How I Help Buyers Select the Correct TNMG 160404

When I evaluate a TNMG 160404 requirement, I first ask for the workpiece material, machine type, operation, insert holder code, target surface finish, and cutting conditions. I also check whether the buyer needs roughing, finishing, interrupted cutting, or stable boring in a continuous cut. This information helps me recommend a suitable grade and chipbreaker instead of treating the ISO code as a complete machining solution.

I also distinguish between dimensional compatibility and process suitability. An insert can fit a holder mechanically but still perform poorly because the grade is unsuitable, the chipbreaker does not match the feed range, or the 0.4 mm radius is too small for the required load. Where exact performance depends on unconfirmed machine or material information, I provide a conservative recommendation and request a sample drawing or machining specification before finalizing the supply.

Buyer Factors: Grade, Coating, Quantity, and Quality Control

Buyers should compare more than the printed insert code. Important factors include carbide substrate, coating system, edge preparation, chipbreaker range, corner consistency, packaging, and traceability. For repeat production, I recommend confirming the same geometry and grade across future batches because changing the chipbreaker or edge preparation can alter cutting forces and chip control.

Order quantity and lead time also depend on whether the requirement is a standard catalog item, a private-label product, or a customized grade and chipbreaker. At KEUE CNC, I can discuss standard supply, OEM or private-label requirements, packaging preferences, and boring-tool matching. Final pricing and delivery are confirmed after reviewing the requested specification, quantity, and production schedule rather than promising a universal lead time.

Key Takeaways

• TNMG 160404 is a triangular, negative-clearance insert with a nominal 0.4 mm nose radius.
• Typical reference dimensions are approximately 9.525 mm inscribed circle and 4.76 mm thickness.
• It is used for turning and boring, but performance depends on the grade, coating, chipbreaker, and cutting conditions.
• Compatibility requires a TNMG negative-style holder matched to the 1604 size, orientation, clamping method, and operation.
• A suitable holder and insert grade should be selected together, especially for internal boring and long overhangs.

Conclusion: Is TNMG 160404 Right for Your Tooling?

TNMG 160404 is a practical general-purpose insert specification for rigid turning and boring setups when the required dimensions, holder, workpiece material, and cutting conditions are properly matched. Its approximately 0.4 mm nose radius offers a useful compromise between cutting access and corner strength, while the negative geometry supports stable machining with an appropriate toolholder. It is not a universal solution, so I recommend confirming the exact insert drawing and holder code before ordering.

To proceed, send me your workpiece material, machine type, internal or external operation, existing holder or boring bar code, and expected order quantity. KEUE CNC can then help you verify TNMG 160404 dimensions, select a compatible boring tool, and determine the appropriate grade, coating, and chipbreaker for your application. This approach reduces fitment risk and gives your purchasing team a clearer basis for repeat supply.

Contact us to discuss your requirements of Tnmg 160404. Our experienced sales team can help you identify the options that best suit your needs.