CNMM-GX – INNOT insert

CNMM-GX

80° negative insert for heavy roughing of steels, with GX chipbreaker and INNOT CVD grades. For the deepest cuts and the highest feeds.

ISO P
Heavy roughing
CVD
★ IT8115 · IT8225

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Technical data sheet PDFCutting data, sizes and grades

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INNOT grades

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

Standard ISO designation

Compatible with the insert holders you use

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Description

ISO specifications

ISO RADIUS (RE) AVAILABLE GRADES CHIPBREAKER
CNMM1906 0.8 – 1.2 – 1.6 – 2.4 IT8115 – IT8125 – IT8225 – IT8135 GX
CNMM2507 1.6 – 2.4 – 3.2 IT8115 – IT8125 – IT8225 – IT8135 GX
CNMM2509 1.6 – 2.4 – 3.2 IT8115 – IT8125 – IT8225 – IT8135 GX

GX chipbreaker data sheet

Operation Heavy roughing
ISO material P (non-alloy, alloy and tool steels)
Tolerance M
Features Chipbreaker for the heaviest operations. The variable chamfer and the special chipbreaker design ensure excellent chip control; the strong cutting edge withstands heavy impacts. Suitable for depths of cut up to 13 mm and feeds up to 1.3 mm/rev.

Available INNOT grades

Grade ISO Coating Composition Application
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.
IT8135 P CVD TiN + MT-TiCN + Al₂O₃ Grade for turning steel with heavy impacts. High-toughness substrate and reinforced binder phase: excellent impact resistance in heavily interrupted cuts.

★ 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
Heavy external turning of steels (ISO P) – GX chipbreaker

Recommended cutting data by material and cutting condition.

Material Condition Vc (m/min) by grade fn (mm/rev) ap (mm)
Steels ≤ 280 HB
(S235, C45, 41Cr4, 42CrMo4…)		 Stable IT8115: 135 – 220
IT8125: 80 – 140
IT8225: 80 – 160		 0.40 – 1.20 4.50 – 13.00
Steels ≤ 280 HB
(S235, C45, 41Cr4, 42CrMo4…)		 Average IT8115: 100 – 180
IT8125: 100 – 160
IT8225: 115 – 170		 0.40 – 1.15 4.50 – 13.00
Steels ≤ 280 HB
(S235, C45, 41Cr4, 42CrMo4…)		 Difficult IT8115: 60 – 180
IT8125: 60 – 160
IT8225: 60 – 170		 0.40 – 1.10 4.50 – 13.00
Quenched and tempered steels ≥ 280 HB Stable IT8115: 120 – 220
IT8225: 120 – 210		 0.70 – 1.30 4.00 – 12.00
Quenched and tempered steels ≥ 280 HB Average IT8115: 80 – 220
IT8225: 80 – 210		 0.70 – 1.25 4.00 – 12.00

Guide values. IT8135 is the grade for heavy impacts and heavily interrupted cuts: cutting data on request.

Heavy internal turning (boring) of steels (ISO P) – GX 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). Heavy roughing needs rigid boring bars in large bores, indicatively above Ø 60 mm.

Material Condition Vc (m/min) by grade fn (mm/rev) ap (mm)
Steels ≤ 280 HB
(S235, C45, 41Cr4, 42CrMo4…)		 Stable IT8115: 115 – 185
IT8125: 70 – 120
IT8225: 70 – 135		 0.32 – 0.96 4.50 – 7.80
Steels ≤ 280 HB
(S235, C45, 41Cr4, 42CrMo4…)		 Average IT8115: 85 – 155
IT8125: 85 – 135
IT8225: 100 – 145		 0.32 – 0.92 4.50 – 7.80
Steels ≤ 280 HB
(S235, C45, 41Cr4, 42CrMo4…)		 Difficult IT8115: 50 – 155
IT8125: 50 – 135
IT8225: 50 – 145		 0.32 – 0.88 4.50 – 7.80
Quenched and tempered steels ≥ 280 HB Stable IT8115: 100 – 185
IT8225: 100 – 180		 0.56 – 1.04 4.00 – 7.20
Quenched and tempered steels ≥ 280 HB Average IT8115: 70 – 185
IT8225: 70 – 180		 0.56 – 1.00 4.00 – 7.20

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.