CNMG-GM – INNOT insert

CNMG-GM

80° negative insert for semi-finishing steels, with GM chipbreaker and INNOT CVD grades.

ISO P
Semi-finishing
CVD
★ IT8115 · IT8225

Request a quote

Technical data sheet PDFCutting data, sizes and grades

Want to try it first? Request a free tester

Fits on
Boring bars for internal turning95° external turning toolholders

Prices reserved for companiesLog in to your customer area to see your prices and request new ones in one click.
Sign in
Need technical advice? Talk to INNOT

(+39) 375 786 1361 Call · WhatsApp

INNOT grades

CVD, PVD and cermet for ISO P, M, K, S

Standard ISO designation

Compatible with the insert holders you use

Technical support

We help you choose grade and chipbreaker

Shipping in 24/48 h

For stock orders throughout Italy

Categories: ,

Description

ISO specifications

ISO RADIUS (RE) AVAILABLE GRADES CHIPBREAKER
CNMG1204 0.4 – 0.8 – 1.2 IT8105 – IT8115 – IT8125 – IT8225 GM
CNMG1606 0.8 – 1.2 – 1.6 IT8105 – IT8115 – IT8125 – IT8225 GM
CNMG1906 0.8 – 1.2 – 1.6 IT8105 – IT8115 – IT8125 – IT8225 GM

GM chipbreaker data sheet

Operation Semi-finishing
ISO material P (non-alloy, alloy and tool steels)
Tolerance M
Features First choice for semi-finishing ISO P materials. The special edge profile combines sharpness and strength. The curved rake face, with variable land width and rake angle, ensures smooth chip flow and good chip control. Very versatile with a wide application range: efficient on most steel turning operations.

Available INNOT grades

Grade ISO Coating Composition Application
IT8105 P CVD TiN + MT-TiCN + Al₂O₃ Turning of steel in stable conditions. High hot hardness, resistance to wear and plastic deformation.
IT8115 ★ P CVD TiN + MT-TiCN + Al₂O₃ Continuous and lightly interrupted cuts. Finishing and semi-finishing of carbon and alloy steels.
IT8125 P CVD TiN + MT-TiCN + Al₂O₃ Interrupted and continuous cuts on steel. The reinforced substrate limits plastic deformation at high temperature.
IT8225 ★ P CVD TiN + MT-TiCN + Al₂O₃ First-choice grade for steel, very versatile. Multilayer coating with excellent wear resistance and toughness.

★ Recommended grade for this chipbreaker. CVD = chemical vapour deposition coating. ISO P = steels.

Recommended cutting data

Printable cutting data tableAll the data on this page in an INNOT PDF to keep in the shop.Download PDF
External turning of steels (ISO P) – GM chipbreaker

Recommended cutting data by material and cutting condition (stable, average, difficult).

Material Condition Vc (m/min) by grade fn (mm/rev) ap (mm)
Structural steels ≤ 180 HB
(S235, C45…)		 Stable IT8105: 230 – 400
IT8115: 215 – 360
IT8125: 190 – 355
IT8225: 205 – 375		 0.16 – 0.55 1.00 – 5.00
Structural steels ≤ 180 HB
(S235, C45…)		 Average IT8105: 225 – 380
IT8115: 200 – 380
IT8125: 185 – 350
IT8225: 195 – 360		 0.16 – 0.50 1.00 – 5.00
Structural steels ≤ 180 HB
(S235, C45…)		 Difficult IT8125: 185 – 320
IT8225: 195 – 360		 0.16 – 0.45 1.00 – 5.00
Carbon and alloy steels 180 – 280 HB
(41Cr4, 42CrMo4…)		 Stable IT8105: 230 – 400
IT8115: 215 – 360
IT8125: 190 – 355
IT8225: 205 – 375		 0.16 – 0.55 1.00 – 5.00
Carbon and alloy steels 180 – 280 HB
(41Cr4, 42CrMo4…)		 Average IT8105: 225 – 430
IT8115: 200 – 405
IT8125: 185 – 350
IT8225: 195 – 360		 0.16 – 0.50 1.00 – 5.00
Carbon and alloy steels 180 – 280 HB
(41Cr4, 42CrMo4…)		 Difficult IT8125: 185 – 350
IT8225: 195 – 360		 0.16 – 0.45 1.00 – 5.00
Quenched and tempered steels ≥ 280 HB Stable IT8105: 220 – 400
IT8115: 205 – 380		 0.20 – 0.55 1.00 – 4.00
Quenched and tempered steels ≥ 280 HB Average IT8105: 220 – 380
IT8115: 205 – 360		 0.20 – 0.50 1.00 – 4.00

Guide values for the GM chipbreaker. Conditions not shown are not recommended for that material.

Internal turning (boring) of steels (ISO P) – GM chipbreaker

Starting values for internal turning with a boring bar, derived from this insert's external turning data: cutting speed −15%, feed −20%, maximum depth of cut −40%. Negative inserts are mounted on boring bars for bores from about Ø 25 mm upwards (Ø 32–40 mm for the larger sizes).

Material Condition Vc (m/min) by grade fn (mm/rev) ap (mm)
Structural steels ≤ 180 HB
(S235, C45…)		 Stable IT8105: 195 – 340
IT8115: 185 – 305
IT8125: 160 – 300
IT8225: 175 – 320		 0.13 – 0.44 1.00 – 3.00
Structural steels ≤ 180 HB
(S235, C45…)		 Average IT8105: 190 – 325
IT8115: 170 – 325
IT8125: 155 – 300
IT8225: 165 – 305		 0.13 – 0.40 1.00 – 3.00
Structural steels ≤ 180 HB
(S235, C45…)		 Difficult IT8125: 155 – 270
IT8225: 165 – 305		 0.13 – 0.36 1.00 – 3.00
Carbon and alloy steels 180 – 280 HB
(41Cr4, 42CrMo4…)		 Stable IT8105: 195 – 340
IT8115: 185 – 305
IT8125: 160 – 300
IT8225: 175 – 320		 0.13 – 0.44 1.00 – 3.00
Carbon and alloy steels 180 – 280 HB
(41Cr4, 42CrMo4…)		 Average IT8105: 190 – 365
IT8115: 170 – 345
IT8125: 155 – 300
IT8225: 165 – 305		 0.13 – 0.40 1.00 – 3.00
Carbon and alloy steels 180 – 280 HB
(41Cr4, 42CrMo4…)		 Difficult IT8125: 155 – 300
IT8225: 165 – 305		 0.13 – 0.36 1.00 – 3.00
Quenched and tempered steels ≥ 280 HB Stable IT8105: 185 – 340
IT8115: 175 – 325		 0.16 – 0.44 1.00 – 2.40
Quenched and tempered steels ≥ 280 HB Average IT8105: 185 – 325
IT8115: 175 – 305		 0.16 – 0.40 1.00 – 2.40

With a boring bar overhang above 3 times the diameter (steel bar) or 5 times (carbide or anti-vibration bar), reduce speed and feed further. Use the bar's internal coolant to clear the chips.