• 98% satisfied customers
  • 72h delivery
  • 30 dni na zwrot
Home
navigate_next
Multi-cutting inserts
navigate_next
Cutting lathe inserts
Carbide insert TNMG 160408 CBN Borazon - nr. 1
search
  • Carbide insert TNMG 160408 CBN Borazon - nr. 1
  • Carbide insert TNMG 160408 CBN Borazon - nr. 2
Horn

Carbide insert TNMG 160408 CBN Horn

Horn Horn
0000004964
Cutting edge length: 162 sizes of this insert
1622
€19.42 tax inc.

Net price: €15.79

Instant Shipping
W magazynie: 10-100 szt.
W magazynie: 10-100 szt.

Instant Shipping

Call and order: (44) 755-04-05

Description

TNMG 160408 CBN turning insert – 60° triangle for hard turning

Technical data
Side length l 16.5 mm
Insert thickness s 4.76 mm
Hole diameter d1 3.81 mm
Corner radius rε 0.8 mm
ANSI code TNMG 332
TNMG 160408 CBN turning insert with a borazon tip, triangular, negative, with a mounting hole and a 0.8 mm nose radius for hard turning

TNMG 160408 turning insert with a borazon (CBN) tip – applications and design

60° triangle for hard turning steel above 45 HRC

The TNMG 160408 CBN turning insert is a triangular insert with a brazed cubic boron nitride (borazon) tip, designed for hard turning hardened steels and materials with a hardness above 45 HRC. The T shape, an equilateral triangle with a 60° corner angle, facilitates access to the workpiece contour during longitudinal turning and facing. The base pocket has negative geometry with a 0° clearance angle, and the working corner with a nose radius rε of 0.8 mm combines surface finish with edge durability. Cubic boron nitride is second only to diamond in hardness, so it retains its sharpness where conventional carbide wears rapidly.

Key features of the TNMG 160408 CBN borazon insert

  • Cubic boron nitride (CBN) tip — borazon is the second-hardest cutting tool material after diamond and retains its sharpness when turning hardened materials.
  • Hardness range above 45 HRC — hardened, carburized, and tool steels in which carbide suffers reduced tool life.
  • Corner radius rε 0.8 mm — a balance between surface finish and corner strength at low finishing feeds.
  • The triangular T shape with a 60° corner angle provides good contour access and lower radial forces than a 80° corner.
  • Negative geometry with a mounting hole ensures rigid seating of the insert in the tool holder pocket.
  • Dimensions comply with ISO 1832: edge length 16.5 mm, IC 9.525 mm (3/8″), thickness 4.76 mm — compatible with tool holders with a size 16 triangular pocket.

Applications and selection of hard turning parameters

The TNMG 160408 CBN insert (also written without a space as tnmg160408) is suitable for finish hard turning shafts, bushings, and rings made of hardened, carburized, and tool steels, including interrupted cuts. Calculate spindle speed using the formula n = 1000·Vc/(π·D): for a shaft with a diameter of 50 mm at a cutting speed of Vc = 150 m/min, the result is approximately 955 rpm. For hard turning, maintain a shallow depth of cut and a low feed of approximately 0.05–0.15 mm/rev to reduce forces and protect the brittle borazon edge. The borazon inserts in this range are supplied by the Korean brand Horn.

Hard turning with a borazon insert can be an alternative to grinding — it allows accurate dimensions and low surface roughness to be achieved in a single setup, reducing machining time. This requires a rigid machine tool, minimal workpiece runout, and stable clamping, as CBN does not tolerate vibration or impacts outside the corner area well. Hard turning is often performed dry because the high temperature in the cutting zone promotes plastic flow in the layer being cut and reduces forces. Inserts of this type are also referred to as turning inserts for hardened steel.

▲
Application limitation

A borazon insert is uneconomical and prone to rapid wear in steel that is unhardened and in ductile materials (mild steel, aluminum). For structural steel and stainless steel, choose an insert made of cemented carbide; CBN is only justified at a hardness of 45 HRC.

Triangular insert designation decoder according to ISO 1832

how to read the TNMG 160408 code — positions 1–7 of the designation

Designation TNMG 160408 according to the standard ISO 1832: 4 letters describe geometry and construction, 3 numeric codes describe dimensions. Each field has a number, an icon, and a brief description.

ISO 1832 designation decoder — how to read the code

1Tshape 2Nangle α 3Mtolerance 4Gtype – 516size 604thickness 708radius rε

Positions 1–4 · ISO code

1TShape

60° triangle

3 corners of 60° per side

2NClearance angle

α = 0°

negative, double-sided

3MTolerance

Class M (intermediate)

IC ±0.05 · thickness ±0.13 mm

4GType

Hole + chip breaker

chip breaker on both sides

Positions 5–7 · dimensions [mm]

516Size

l = 16.5 mm

IC = 9.525 mm · 3/8″

604Thickness

s = 4.76 mm

between rake faces

708Corner radius

rε = 0.8 mm

code ÷ 10 → radius in mm

✓ 3 corners × 2 sides = 6 cutting edges

Full designation: TNMG 160408 = 60° triangle · negative · class M · hole and chip breaker · IC 9.525 mm (l 16.5 mm) · s 4.76 mm · rε 0.8 mm

Compatible turning tools

holders with a 16 triangular pocket — external and internal turning

TTJNR/L 2020 K1620×20 × 125 mmR right-hand
←L left-hand
→
TTJNR/L 2525 M1625×25 × 150 mmR right-hand
←L left-hand
→
TTJNR/L 3232 P1632×32 × 170 mmR right-hand
←L left-hand
→
TTENN 2020 K1620×20 × 125 mmNeutral
↔
TTENN 2525 M1625×25 × 150 mmNeutral
↔
TTENN 3232 P1632×32 × 170 mmNeutral
↔
TTGNR/L 2020 K1620×20 × 125 mmR right-hand
←L left-hand
→
TTGNR/L 2525 M1625×25 × 150 mmR right-hand
←L left-hand
→
TTGNR/L 3232 P1632×32 × 170 mmR right-hand
←L left-hand
→
TTFNR/L 2020 K1620×20 × 125 mmR right-hand
←L left-hand
→
TTFNR/L 2525 M1625×25 × 150 mmR right-hand
←L left-hand
→
TTFNR/L 3232 P1632×32 × 170 mmR right-hand
←L left-hand
→
MTJNR/L 2020 K1620×20 × 125 mmR right-hand
←L left-hand
→
MTJNR/L 2525 M1625×25 × 150 mmR right-hand
←L left-hand
→
MTJNR/L 3232 P1632×32 × 170 mmR right-hand
←L left-hand
→
MTENN 2020 K1620×20 × 125 mmNeutral
↔
MTENN 2525 M1625×25 × 150 mmNeutral
↔
MTENN 3232 P1632×32 × 170 mmNeutral
↔
S25S TTUNR/L-16ø25 × 250 mm | D min ≥32R right-hand
←L left-hand
→
S32T TTUNR/L-16ø32 × 300 mm | D min ≥40R right-hand
←L left-hand
→
S25S TT-NR/L-16ø25 × 250 mm | D min ≥32R right-hand
←L left-hand
→
S32T TT-NR/L-16ø32 × 300 mm | D min ≥40R right-hand
←L left-hand
→
S20R MTUNR/L-16ø20 × 200 mm | D min ≥25R right-hand
←L left-hand
→
S25S MTUNR/L-16ø25 × 250 mm | D min ≥32R right-hand
←L left-hand
→
S32T MTUNR/L-16ø32 × 300 mm | D min ≥40R right-hand
←L left-hand
→
S40U MTUNR/L-16ø40 × 350 mm | D min ≥50R right-hand
←L left-hand
→
S20R MTQNR/L-16ø20 × 200 mm | D min ≥25R right-hand
←L left-hand
→
S25S MTQNR/L-16ø25 × 250 mm | D min ≥32R right-hand
←L left-hand
→
S32T MTQNR/L-16ø32 × 300 mm | D min ≥40R right-hand
←L left-hand
→
S40U MTQNR/L-16ø40 × 350 mm | D min ≥50R right-hand
←L left-hand
→

Frequently asked questions about the TNMG 160408 CBN insert

materials, number of cutting edges, turning tool selection, and nose radius

For hard turning hardened, carburized, and tool steels with a hardness above 45 HRC, including interrupted cuts. Cubic boron nitride (borazon) retains its sharpness where carbide wears rapidly. In unhardened steel and ductile materials, a borazon insert is uneconomical.

The basic TNMG geometry is triangular and negative, providing up to six corners, but in the borazon version, the number of usable cutting edges depends on the number of brazed CBN tips. Once an edge is worn, simply index the insert in the pocket to the next borazon corner.

Holders with a 16 triangular pocket (IC 9.525 mm): for external turning TTJNR/L and MTJNR/L, TTFNR/L and TTGNR/L and neutral TTENN and MTENN with cross sections of 20×20–32×32 mm; for internal turning, boring bars S20R–S40U with a TTUNR/L, MTUNR/L or MTQNR/L designation suffix.

The nose radius affects surface finish and cutting edge strength: 0.4 mm is used for precision finishing at low feeds, 0.8 mm is the general-purpose version, and 1.2 mm is selected for heavier cuts. The remaining dimensions (IC 9.525 mm, thickness 4.76 mm) in the TNMG 1604 family are identical.

Product accessories

Reviews

No customer reviews for the moment.

Add a review about the product

Carbide insert TNMG 160408 CBN Horn

Carbide insert TNMG 160408 CBN Horn

Shipping

All orders are delivered by courier company GLS. For orders exceeding 369 PLN gross shipping is FREE

Courier GLS Przelew24 / Prepayment 14,76 zł gross Delivery time 1 working day
Courier GLS Cash on delivery 17,26 zł gross Lead time 1 working day

Recommended for you

Viewed products

This website uses its own and third-party cookies to improve our services and show you advertising related to your preferences by analyzing your browsing habits. To give your consent to its use, press the Accept button.

More information