Yes, you can drill a square hole with a round bit. Here's how: An auger-type drill bit spins inside a hollow four-sided chisel secured to the mortiser. The bit itself locks into a drill chuck inside the head of the machine. When you pull down on the mortiser's feed lever, the bit and chisel plunge simultaneously into your workpiece.

1 – Without a fixing Hole: This option is used mainly on ceramic and full CBN inserts, where there is a technological problem with producing the insert with a hole or clamping it with the hole, which will break it.

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The fourth symbol (strangely) defines a combination of 2 unconnected properties:Mounting style: Describes how the insert can be clamped on the tool holder.Chip Breaker: Describes if a chip breaker exists and on which side of the insert. It does not say anything about its geometry.SymbolClamping MethodChip BreakerNegative InsertPositive InsertsGCylindrical fixing holeChip breakers on both facesMCylindrical fixing holeChip breakers on one face onlyACylindrical fixing holeWithout chip breakersTCylindrical fixing hole, with 40°-60° countersink on one sideChip breakers on one face onlyWCylindrical fixing hole, with 40°-60° countersink on one sideWithout chip breakersUCylindrical fixing hole, with 40°-60° countersinks on both sidesChip breakers on both facesQCylindrical fixing hole, with 40°-60° countersinks on both sidesWithout chip breakersHCylindrical fixing hole, with 70°-90° countersink on one sideChip breakers on one face onlyBCylindrical fixing hole, with 70°-90° countersink on one sideWithout chip breakersJCylindrical fixing hole, with 70°-90° countersinks on both sidesChip breakers on both facesCCylindrical fixing hole, with 70°-90° countersinks on both sidesWithout chip breakersFWithout a fixing holeChip breakers on both facesRWithout a fixing holeChip breakers on one face onlyNWithout a fixing holeWithout chip breakersXX - Special - Requires detailed explanation/drawingX - Special - Requires detailed explanation/drawingThere are 3 main mounting style options (Parameter code IFS that can equal 1, 2, or 3):1 – Without a fixing Hole: This option is used mainly on ceramic and full CBN inserts, where there is a technological problem with producing the insert with a hole or clamping it with the hole, which will break it.2 – Cylindrical hole: Used with “Lever-Lock” clamping mechanism. This method utilizes an L-shaped lever to clamp the insert against two walls of the insert pocket.Advantages:Quick and easy indexing.No falling parts.Disadvantages:It requires more space in the cutting tool to house the mechanism, thus making it less suitable for smaller holders and internal tools for small bore diameters.The force vector that pushes the insert down is small; therefore, it is less stable.To solve this problem, a top clamp is sometimes added; however, this removes some advantages.3 – Cylindrical hole with countersinks: The insert is clamped with a screw that secures the insert against two walls and also forces it downwards.Advantages:Very simple design and production.Takes minimum space in the cutting tool.Secures the inserts in 3 directions.Best for small and internal tools.Disadvantages:Slower indexing.Falling parts (Easy to lose the screw)SizeCNMG120408432The insert’s size symbol works differently in the ISO and ANSI conventions:ISOANSILength of cutting edgeShape’s inscribed circleEquals approximately the length (In mm)Equals approximately 8*IC (In Inches)Each shape has a different list of symbolsSame symbol for all shapesSize Symbol ChartFor ISO (Metric) size, check under the relevant shape symbolInscribed Circle DiameterANSI (Inch) Size SymbolISO (Metric) Size Symbol per Insert ShapemmInchSTCDEVWR3.970.156251.20306X04X0602X4.760.18751.5040804050408L3X5.560.218751.805090506050903X6.350.25206110607061104067.940.31252.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131mmInchANSISymbolSTCDEVWR3.970.1561.20306X04X0602X4.760.1871.5040804050408L3X5.560.2191.805090506050903X6.350.25206110607061104067.940.3132.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131Round Metric Inserts (With “M0” suffix)In the metric designation of round inserts (R Shape), it is possible to add the “M0” suffix (For example, RNMG 1204-M0).In such a case, the diameter is metric, and the table below should be used (Instead of the above)Pay attention! RNMG 1204 (or RNMG 120400) has a diameter of 12.7 mm, but RNMG 1204-M0 has a diameter of 12.0 mm!symbolDiameter066 mm (0,236″)088 mm (0,315″)1010 mm (0,394″)1212 mm (0,472″)1616 mm (0,63″)2020 mm (0,787″)2525 mm (0,984″)3232 mm (1,26″)ThicknessCNMG120408432The thickness is measured from the clamping (bottom) plane to the highest point of the cutting edge (Not the top plane). The symbol represents the thickness differently in metric and inch description formats:ISO (Metric): The symbol is approximately the thickness in millimeters.The first digit is always zero (See exception in the next bullet).When there are 2 nearby values (3.18 / 3.97), the zero is replaced by T for the larger one.ANSI (Inch): The symbol is 16 times the thickness (in inches)Symbol (ISO)Symbol (ANSI)dropdown_mmdropdown_inchThickness (mm)Thickness (Inch)01101 (1.59 mm)1 (0.0625")1.590.0625021.502 (2.38 mm)1.5 (0.09375")2.380.093803203 (3.18 mm)2 (0.125")3.180.125004304 (4.76 mm)3 (0.1875")4.760.1875053.505 (5.56 mm)3.5 (0.21875")5.560.218806406 (6.35 mm)4 (0.25")6.350.250007507 (7.94 mm)5 (0.3125")7.940.312509609 (9.52 mm)6 (0.375")9.520.375012812 (12.7 mm)8 (0.5")12.700.5000T11.2T1 (1.98 mm)1.2 (0.078125")1.980.0781T32.5T3 (3.97 mm)2.5 (0.15625")3.970.1563Corner RadiusCNMG120408432ISO (Metric): The symbol is the corner radius in millimeters times 10.If the result is less than 10, a leading zero is added.ANSI (Inch): The symbol is 64 times the corner radius in inches.If the result is more than one, it is rounded to the nearest integer.If the result is less than one, it is rounded to the next 0.25 multiple.Symbol (ISO)Symbol (ANSI)Radius (mm)Radius (Inch)dropdown_mmdropdown_inch0000.00.000000 (0.0 mm)0 (0")010.250.10.004001 (0.1 mm)0.25 (0.004")020.50.20.008002 (0.2 mm)0.5 (0.008")0410.40.015604 (0.4 mm)1 (0.0156")0820.80.031308 (0.8 mm)2 (0.0313")1231.20.046912 (1.2 mm)3 (0.0469")1641.60.062516 (1.6 mm)4 (0.0625")2462.40.093824 (2.4 mm)6 (0.0938")3283.20.125032 (3.2 mm)8 (0.125")Popular Turning InsertsAlthough the possible combinations are endless, only a handful of them are practically offered by most of the cutting tool suppliers.The table below lists the typical offerings. While there are other inserts in the market not listed here, 90% of the offerings are included.(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts

There are 3 main mounting style options (Parameter code IFS that can equal 1, 2, or 3):1 – Without a fixing Hole: This option is used mainly on ceramic and full CBN inserts, where there is a technological problem with producing the insert with a hole or clamping it with the hole, which will break it.2 – Cylindrical hole: Used with “Lever-Lock” clamping mechanism. This method utilizes an L-shaped lever to clamp the insert against two walls of the insert pocket.Advantages:Quick and easy indexing.No falling parts.Disadvantages:It requires more space in the cutting tool to house the mechanism, thus making it less suitable for smaller holders and internal tools for small bore diameters.The force vector that pushes the insert down is small; therefore, it is less stable.To solve this problem, a top clamp is sometimes added; however, this removes some advantages.3 – Cylindrical hole with countersinks: The insert is clamped with a screw that secures the insert against two walls and also forces it downwards.Advantages:Very simple design and production.Takes minimum space in the cutting tool.Secures the inserts in 3 directions.Best for small and internal tools.Disadvantages:Slower indexing.Falling parts (Easy to lose the screw)SizeCNMG120408432The insert’s size symbol works differently in the ISO and ANSI conventions:ISOANSILength of cutting edgeShape’s inscribed circleEquals approximately the length (In mm)Equals approximately 8*IC (In Inches)Each shape has a different list of symbolsSame symbol for all shapesSize Symbol ChartFor ISO (Metric) size, check under the relevant shape symbolInscribed Circle DiameterANSI (Inch) Size SymbolISO (Metric) Size Symbol per Insert ShapemmInchSTCDEVWR3.970.156251.20306X04X0602X4.760.18751.5040804050408L3X5.560.218751.805090506050903X6.350.25206110607061104067.940.31252.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131mmInchANSISymbolSTCDEVWR3.970.1561.20306X04X0602X4.760.1871.5040804050408L3X5.560.2191.805090506050903X6.350.25206110607061104067.940.3132.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131Round Metric Inserts (With “M0” suffix)In the metric designation of round inserts (R Shape), it is possible to add the “M0” suffix (For example, RNMG 1204-M0).In such a case, the diameter is metric, and the table below should be used (Instead of the above)Pay attention! RNMG 1204 (or RNMG 120400) has a diameter of 12.7 mm, but RNMG 1204-M0 has a diameter of 12.0 mm!symbolDiameter066 mm (0,236″)088 mm (0,315″)1010 mm (0,394″)1212 mm (0,472″)1616 mm (0,63″)2020 mm (0,787″)2525 mm (0,984″)3232 mm (1,26″)ThicknessCNMG120408432The thickness is measured from the clamping (bottom) plane to the highest point of the cutting edge (Not the top plane). The symbol represents the thickness differently in metric and inch description formats:ISO (Metric): The symbol is approximately the thickness in millimeters.The first digit is always zero (See exception in the next bullet).When there are 2 nearby values (3.18 / 3.97), the zero is replaced by T for the larger one.ANSI (Inch): The symbol is 16 times the thickness (in inches)Symbol (ISO)Symbol (ANSI)dropdown_mmdropdown_inchThickness (mm)Thickness (Inch)01101 (1.59 mm)1 (0.0625")1.590.0625021.502 (2.38 mm)1.5 (0.09375")2.380.093803203 (3.18 mm)2 (0.125")3.180.125004304 (4.76 mm)3 (0.1875")4.760.1875053.505 (5.56 mm)3.5 (0.21875")5.560.218806406 (6.35 mm)4 (0.25")6.350.250007507 (7.94 mm)5 (0.3125")7.940.312509609 (9.52 mm)6 (0.375")9.520.375012812 (12.7 mm)8 (0.5")12.700.5000T11.2T1 (1.98 mm)1.2 (0.078125")1.980.0781T32.5T3 (3.97 mm)2.5 (0.15625")3.970.1563Corner RadiusCNMG120408432ISO (Metric): The symbol is the corner radius in millimeters times 10.If the result is less than 10, a leading zero is added.ANSI (Inch): The symbol is 64 times the corner radius in inches.If the result is more than one, it is rounded to the nearest integer.If the result is less than one, it is rounded to the next 0.25 multiple.Symbol (ISO)Symbol (ANSI)Radius (mm)Radius (Inch)dropdown_mmdropdown_inch0000.00.000000 (0.0 mm)0 (0")010.250.10.004001 (0.1 mm)0.25 (0.004")020.50.20.008002 (0.2 mm)0.5 (0.008")0410.40.015604 (0.4 mm)1 (0.0156")0820.80.031308 (0.8 mm)2 (0.0313")1231.20.046912 (1.2 mm)3 (0.0469")1641.60.062516 (1.6 mm)4 (0.0625")2462.40.093824 (2.4 mm)6 (0.0938")3283.20.125032 (3.2 mm)8 (0.125")Popular Turning InsertsAlthough the possible combinations are endless, only a handful of them are practically offered by most of the cutting tool suppliers.The table below lists the typical offerings. While there are other inserts in the market not listed here, 90% of the offerings are included.(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts

The thickness is measured from the clamping (bottom) plane to the highest point of the cutting edge (Not the top plane). The symbol represents the thickness differently in metric and inch description formats:

2 – Cylindrical hole: Used with “Lever-Lock” clamping mechanism. This method utilizes an L-shaped lever to clamp the insert against two walls of the insert pocket.

Additionally, the standard defines the tolerance only for 3 parameters:d – Inscribed circle diameter: The limit on the insert size.m – Cutting edge position: This is an important parameter since it defines the repeatability you can expect on the turned diameter when indexing a corner or replacing an insert.s – Insert thickness: Effect the reputability of the cutting edge height. It is an important parameter when machining small diameters.All the many other properties of a turning insert (Including the nose radius) are not defined, and each manufacturer has its own internal standard, which he usually does not make public.How to use the tolerance charts below?Although the chart includes 12 tolerance classes, only two are used in practice!M – For pressed inserts.G – For ground inserts.E – Very rarely used. It is the same as G but with striker thickness tolerance.The first chart provides the basic values. If a cell is empty, obtain the value from the second chart based on the insert’s shape and size.Main Tolerance ChartTolerance ClassTolerance of d(IC)Tolerance of m(Edge Position)Tolerance of s(Thickness)M (Pressed Inserts)See next table(According to size and shape)+/-0.013 mm0.0005"G (Ground Inserts)+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"E+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"A+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"F+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"C+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"H+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"J+/-0.013 mm0.0005"+/-0.013 mm0.0005"K+/-0.013 mm0.0005"+/-0.013 mm0.0005"L+/-0.013 mm0.0005"+/-0.013 mm0.0005"N+/-0.013 mm0.0005"U+/-0.013 mm0.0005"Complimentary Tolerance ChartShapeSize (IC)Tolerance on dTolerance on mD4 - 10 mm3/16-3/8"+/- 0.05 mm+/- 0.002"+/- 0.11 mm+/- 0.004"12.7 mm1/2"+/- 0.08 mm+/- 0.003"+/- 0.15mm+/- 0.006"15.87-19.055/8-3/4"+/- 0.1 mm+/- 0.004"+/- 0.18 mm+/- 0.007"VAny Size+/- 0.05 mm+/- 0.002"+/- 0.16 mm+/- 0.006"All other Shapes4 - 10 mm3/16-3/8"+/- 0.05 mm+/- 0.002"+/- 0.08 mm+/- 0.003"12.0-12.7 mm1/2"+/- 0.08 mm+/- 0.003"+/- 0.13 mm+/- 0.005"15.87-20 mm5/8-3/4"+/- 0.1 mm+/- 0.004"+/- 0.15mm+/- 0.006"25.0-25.4 mm1"+/- 0.13 mm+/- 0.005"+/- 0.18 mm+/- 0.007"31.75 - 32 mm1 1/4""+/- 0.15mm+/- 0.006"+/- 0.2 mm+/- 0.008"Configuration (Mounting style and Chip breaker)CNMG120408The fourth symbol (strangely) defines a combination of 2 unconnected properties:Mounting style: Describes how the insert can be clamped on the tool holder.Chip Breaker: Describes if a chip breaker exists and on which side of the insert. It does not say anything about its geometry.SymbolClamping MethodChip BreakerNegative InsertPositive InsertsGCylindrical fixing holeChip breakers on both facesMCylindrical fixing holeChip breakers on one face onlyACylindrical fixing holeWithout chip breakersTCylindrical fixing hole, with 40°-60° countersink on one sideChip breakers on one face onlyWCylindrical fixing hole, with 40°-60° countersink on one sideWithout chip breakersUCylindrical fixing hole, with 40°-60° countersinks on both sidesChip breakers on both facesQCylindrical fixing hole, with 40°-60° countersinks on both sidesWithout chip breakersHCylindrical fixing hole, with 70°-90° countersink on one sideChip breakers on one face onlyBCylindrical fixing hole, with 70°-90° countersink on one sideWithout chip breakersJCylindrical fixing hole, with 70°-90° countersinks on both sidesChip breakers on both facesCCylindrical fixing hole, with 70°-90° countersinks on both sidesWithout chip breakersFWithout a fixing holeChip breakers on both facesRWithout a fixing holeChip breakers on one face onlyNWithout a fixing holeWithout chip breakersXX - Special - Requires detailed explanation/drawingX - Special - Requires detailed explanation/drawingThere are 3 main mounting style options (Parameter code IFS that can equal 1, 2, or 3):1 – Without a fixing Hole: This option is used mainly on ceramic and full CBN inserts, where there is a technological problem with producing the insert with a hole or clamping it with the hole, which will break it.2 – Cylindrical hole: Used with “Lever-Lock” clamping mechanism. This method utilizes an L-shaped lever to clamp the insert against two walls of the insert pocket.Advantages:Quick and easy indexing.No falling parts.Disadvantages:It requires more space in the cutting tool to house the mechanism, thus making it less suitable for smaller holders and internal tools for small bore diameters.The force vector that pushes the insert down is small; therefore, it is less stable.To solve this problem, a top clamp is sometimes added; however, this removes some advantages.3 – Cylindrical hole with countersinks: The insert is clamped with a screw that secures the insert against two walls and also forces it downwards.Advantages:Very simple design and production.Takes minimum space in the cutting tool.Secures the inserts in 3 directions.Best for small and internal tools.Disadvantages:Slower indexing.Falling parts (Easy to lose the screw)SizeCNMG120408432The insert’s size symbol works differently in the ISO and ANSI conventions:ISOANSILength of cutting edgeShape’s inscribed circleEquals approximately the length (In mm)Equals approximately 8*IC (In Inches)Each shape has a different list of symbolsSame symbol for all shapesSize Symbol ChartFor ISO (Metric) size, check under the relevant shape symbolInscribed Circle DiameterANSI (Inch) Size SymbolISO (Metric) Size Symbol per Insert ShapemmInchSTCDEVWR3.970.156251.20306X04X0602X4.760.18751.5040804050408L3X5.560.218751.805090506050903X6.350.25206110607061104067.940.31252.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131mmInchANSISymbolSTCDEVWR3.970.1561.20306X04X0602X4.760.1871.5040804050408L3X5.560.2191.805090506050903X6.350.25206110607061104067.940.3132.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131Round Metric Inserts (With “M0” suffix)In the metric designation of round inserts (R Shape), it is possible to add the “M0” suffix (For example, RNMG 1204-M0).In such a case, the diameter is metric, and the table below should be used (Instead of the above)Pay attention! RNMG 1204 (or RNMG 120400) has a diameter of 12.7 mm, but RNMG 1204-M0 has a diameter of 12.0 mm!symbolDiameter066 mm (0,236″)088 mm (0,315″)1010 mm (0,394″)1212 mm (0,472″)1616 mm (0,63″)2020 mm (0,787″)2525 mm (0,984″)3232 mm (1,26″)ThicknessCNMG120408432The thickness is measured from the clamping (bottom) plane to the highest point of the cutting edge (Not the top plane). The symbol represents the thickness differently in metric and inch description formats:ISO (Metric): The symbol is approximately the thickness in millimeters.The first digit is always zero (See exception in the next bullet).When there are 2 nearby values (3.18 / 3.97), the zero is replaced by T for the larger one.ANSI (Inch): The symbol is 16 times the thickness (in inches)Symbol (ISO)Symbol (ANSI)dropdown_mmdropdown_inchThickness (mm)Thickness (Inch)01101 (1.59 mm)1 (0.0625")1.590.0625021.502 (2.38 mm)1.5 (0.09375")2.380.093803203 (3.18 mm)2 (0.125")3.180.125004304 (4.76 mm)3 (0.1875")4.760.1875053.505 (5.56 mm)3.5 (0.21875")5.560.218806406 (6.35 mm)4 (0.25")6.350.250007507 (7.94 mm)5 (0.3125")7.940.312509609 (9.52 mm)6 (0.375")9.520.375012812 (12.7 mm)8 (0.5")12.700.5000T11.2T1 (1.98 mm)1.2 (0.078125")1.980.0781T32.5T3 (3.97 mm)2.5 (0.15625")3.970.1563Corner RadiusCNMG120408432ISO (Metric): The symbol is the corner radius in millimeters times 10.If the result is less than 10, a leading zero is added.ANSI (Inch): The symbol is 64 times the corner radius in inches.If the result is more than one, it is rounded to the nearest integer.If the result is less than one, it is rounded to the next 0.25 multiple.Symbol (ISO)Symbol (ANSI)Radius (mm)Radius (Inch)dropdown_mmdropdown_inch0000.00.000000 (0.0 mm)0 (0")010.250.10.004001 (0.1 mm)0.25 (0.004")020.50.20.008002 (0.2 mm)0.5 (0.008")0410.40.015604 (0.4 mm)1 (0.0156")0820.80.031308 (0.8 mm)2 (0.0313")1231.20.046912 (1.2 mm)3 (0.0469")1641.60.062516 (1.6 mm)4 (0.0625")2462.40.093824 (2.4 mm)6 (0.0938")3283.20.125032 (3.2 mm)8 (0.125")Popular Turning InsertsAlthough the possible combinations are endless, only a handful of them are practically offered by most of the cutting tool suppliers.The table below lists the typical offerings. While there are other inserts in the market not listed here, 90% of the offerings are included.(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts

Disadvantages:It requires more space in the cutting tool to house the mechanism, thus making it less suitable for smaller holders and internal tools for small bore diameters.The force vector that pushes the insert down is small; therefore, it is less stable.To solve this problem, a top clamp is sometimes added; however, this removes some advantages.

(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts

All the many other properties of a turning insert (Including the nose radius) are not defined, and each manufacturer has its own internal standard, which he usually does not make public.How to use the tolerance charts below?Although the chart includes 12 tolerance classes, only two are used in practice!M – For pressed inserts.G – For ground inserts.E – Very rarely used. It is the same as G but with striker thickness tolerance.The first chart provides the basic values. If a cell is empty, obtain the value from the second chart based on the insert’s shape and size.Main Tolerance ChartTolerance ClassTolerance of d(IC)Tolerance of m(Edge Position)Tolerance of s(Thickness)M (Pressed Inserts)See next table(According to size and shape)+/-0.013 mm0.0005"G (Ground Inserts)+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"E+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"A+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"F+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"C+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"H+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"J+/-0.013 mm0.0005"+/-0.013 mm0.0005"K+/-0.013 mm0.0005"+/-0.013 mm0.0005"L+/-0.013 mm0.0005"+/-0.013 mm0.0005"N+/-0.013 mm0.0005"U+/-0.013 mm0.0005"Complimentary Tolerance ChartShapeSize (IC)Tolerance on dTolerance on mD4 - 10 mm3/16-3/8"+/- 0.05 mm+/- 0.002"+/- 0.11 mm+/- 0.004"12.7 mm1/2"+/- 0.08 mm+/- 0.003"+/- 0.15mm+/- 0.006"15.87-19.055/8-3/4"+/- 0.1 mm+/- 0.004"+/- 0.18 mm+/- 0.007"VAny Size+/- 0.05 mm+/- 0.002"+/- 0.16 mm+/- 0.006"All other Shapes4 - 10 mm3/16-3/8"+/- 0.05 mm+/- 0.002"+/- 0.08 mm+/- 0.003"12.0-12.7 mm1/2"+/- 0.08 mm+/- 0.003"+/- 0.13 mm+/- 0.005"15.87-20 mm5/8-3/4"+/- 0.1 mm+/- 0.004"+/- 0.15mm+/- 0.006"25.0-25.4 mm1"+/- 0.13 mm+/- 0.005"+/- 0.18 mm+/- 0.007"31.75 - 32 mm1 1/4""+/- 0.15mm+/- 0.006"+/- 0.2 mm+/- 0.008"Configuration (Mounting style and Chip breaker)CNMG120408The fourth symbol (strangely) defines a combination of 2 unconnected properties:Mounting style: Describes how the insert can be clamped on the tool holder.Chip Breaker: Describes if a chip breaker exists and on which side of the insert. It does not say anything about its geometry.SymbolClamping MethodChip BreakerNegative InsertPositive InsertsGCylindrical fixing holeChip breakers on both facesMCylindrical fixing holeChip breakers on one face onlyACylindrical fixing holeWithout chip breakersTCylindrical fixing hole, with 40°-60° countersink on one sideChip breakers on one face onlyWCylindrical fixing hole, with 40°-60° countersink on one sideWithout chip breakersUCylindrical fixing hole, with 40°-60° countersinks on both sidesChip breakers on both facesQCylindrical fixing hole, with 40°-60° countersinks on both sidesWithout chip breakersHCylindrical fixing hole, with 70°-90° countersink on one sideChip breakers on one face onlyBCylindrical fixing hole, with 70°-90° countersink on one sideWithout chip breakersJCylindrical fixing hole, with 70°-90° countersinks on both sidesChip breakers on both facesCCylindrical fixing hole, with 70°-90° countersinks on both sidesWithout chip breakersFWithout a fixing holeChip breakers on both facesRWithout a fixing holeChip breakers on one face onlyNWithout a fixing holeWithout chip breakersXX - Special - Requires detailed explanation/drawingX - Special - Requires detailed explanation/drawingThere are 3 main mounting style options (Parameter code IFS that can equal 1, 2, or 3):1 – Without a fixing Hole: This option is used mainly on ceramic and full CBN inserts, where there is a technological problem with producing the insert with a hole or clamping it with the hole, which will break it.2 – Cylindrical hole: Used with “Lever-Lock” clamping mechanism. This method utilizes an L-shaped lever to clamp the insert against two walls of the insert pocket.Advantages:Quick and easy indexing.No falling parts.Disadvantages:It requires more space in the cutting tool to house the mechanism, thus making it less suitable for smaller holders and internal tools for small bore diameters.The force vector that pushes the insert down is small; therefore, it is less stable.To solve this problem, a top clamp is sometimes added; however, this removes some advantages.3 – Cylindrical hole with countersinks: The insert is clamped with a screw that secures the insert against two walls and also forces it downwards.Advantages:Very simple design and production.Takes minimum space in the cutting tool.Secures the inserts in 3 directions.Best for small and internal tools.Disadvantages:Slower indexing.Falling parts (Easy to lose the screw)SizeCNMG120408432The insert’s size symbol works differently in the ISO and ANSI conventions:ISOANSILength of cutting edgeShape’s inscribed circleEquals approximately the length (In mm)Equals approximately 8*IC (In Inches)Each shape has a different list of symbolsSame symbol for all shapesSize Symbol ChartFor ISO (Metric) size, check under the relevant shape symbolInscribed Circle DiameterANSI (Inch) Size SymbolISO (Metric) Size Symbol per Insert ShapemmInchSTCDEVWR3.970.156251.20306X04X0602X4.760.18751.5040804050408L3X5.560.218751.805090506050903X6.350.25206110607061104067.940.31252.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131mmInchANSISymbolSTCDEVWR3.970.1561.20306X04X0602X4.760.1871.5040804050408L3X5.560.2191.805090506050903X6.350.25206110607061104067.940.3132.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131Round Metric Inserts (With “M0” suffix)In the metric designation of round inserts (R Shape), it is possible to add the “M0” suffix (For example, RNMG 1204-M0).In such a case, the diameter is metric, and the table below should be used (Instead of the above)Pay attention! RNMG 1204 (or RNMG 120400) has a diameter of 12.7 mm, but RNMG 1204-M0 has a diameter of 12.0 mm!symbolDiameter066 mm (0,236″)088 mm (0,315″)1010 mm (0,394″)1212 mm (0,472″)1616 mm (0,63″)2020 mm (0,787″)2525 mm (0,984″)3232 mm (1,26″)ThicknessCNMG120408432The thickness is measured from the clamping (bottom) plane to the highest point of the cutting edge (Not the top plane). The symbol represents the thickness differently in metric and inch description formats:ISO (Metric): The symbol is approximately the thickness in millimeters.The first digit is always zero (See exception in the next bullet).When there are 2 nearby values (3.18 / 3.97), the zero is replaced by T for the larger one.ANSI (Inch): The symbol is 16 times the thickness (in inches)Symbol (ISO)Symbol (ANSI)dropdown_mmdropdown_inchThickness (mm)Thickness (Inch)01101 (1.59 mm)1 (0.0625")1.590.0625021.502 (2.38 mm)1.5 (0.09375")2.380.093803203 (3.18 mm)2 (0.125")3.180.125004304 (4.76 mm)3 (0.1875")4.760.1875053.505 (5.56 mm)3.5 (0.21875")5.560.218806406 (6.35 mm)4 (0.25")6.350.250007507 (7.94 mm)5 (0.3125")7.940.312509609 (9.52 mm)6 (0.375")9.520.375012812 (12.7 mm)8 (0.5")12.700.5000T11.2T1 (1.98 mm)1.2 (0.078125")1.980.0781T32.5T3 (3.97 mm)2.5 (0.15625")3.970.1563Corner RadiusCNMG120408432ISO (Metric): The symbol is the corner radius in millimeters times 10.If the result is less than 10, a leading zero is added.ANSI (Inch): The symbol is 64 times the corner radius in inches.If the result is more than one, it is rounded to the nearest integer.If the result is less than one, it is rounded to the next 0.25 multiple.Symbol (ISO)Symbol (ANSI)Radius (mm)Radius (Inch)dropdown_mmdropdown_inch0000.00.000000 (0.0 mm)0 (0")010.250.10.004001 (0.1 mm)0.25 (0.004")020.50.20.008002 (0.2 mm)0.5 (0.008")0410.40.015604 (0.4 mm)1 (0.0156")0820.80.031308 (0.8 mm)2 (0.0313")1231.20.046912 (1.2 mm)3 (0.0469")1641.60.062516 (1.6 mm)4 (0.0625")2462.40.093824 (2.4 mm)6 (0.0938")3283.20.125032 (3.2 mm)8 (0.125")Popular Turning InsertsAlthough the possible combinations are endless, only a handful of them are practically offered by most of the cutting tool suppliers.The table below lists the typical offerings. While there are other inserts in the market not listed here, 90% of the offerings are included.(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts

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Although the nomenclature of ISO turning inserts is used daily, many people still find it hard to “know it by heart”, and interpret it correctly. You have to browse several charts, and also after that, the answer is not always complete. To make it easier, we developed the ISO Inserts Wizard, which takes away all the hustle. If you want to understand the process, we also provide detailed charts (Based on the official ISO 1832 standard) and explanations on how to interpret them accurately.Online WizardCharts & Theory

For ISO (Metric) size, check under the relevant shape symbolInscribed Circle DiameterANSI (Inch) Size SymbolISO (Metric) Size Symbol per Insert ShapemmInchSTCDEVWR3.970.156251.20306X04X0602X4.760.18751.5040804050408L3X5.560.218751.805090506050903X6.350.25206110607061104067.940.31252.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131mmInchANSISymbolSTCDEVWR3.970.1561.20306X04X0602X4.760.1871.5040804050408L3X5.560.2191.805090506050903X6.350.25206110607061104067.940.3132.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131Round Metric Inserts (With “M0” suffix)In the metric designation of round inserts (R Shape), it is possible to add the “M0” suffix (For example, RNMG 1204-M0).In such a case, the diameter is metric, and the table below should be used (Instead of the above)Pay attention! RNMG 1204 (or RNMG 120400) has a diameter of 12.7 mm, but RNMG 1204-M0 has a diameter of 12.0 mm!symbolDiameter066 mm (0,236″)088 mm (0,315″)1010 mm (0,394″)1212 mm (0,472″)1616 mm (0,63″)2020 mm (0,787″)2525 mm (0,984″)3232 mm (1,26″)ThicknessCNMG120408432The thickness is measured from the clamping (bottom) plane to the highest point of the cutting edge (Not the top plane). The symbol represents the thickness differently in metric and inch description formats:ISO (Metric): The symbol is approximately the thickness in millimeters.The first digit is always zero (See exception in the next bullet).When there are 2 nearby values (3.18 / 3.97), the zero is replaced by T for the larger one.ANSI (Inch): The symbol is 16 times the thickness (in inches)Symbol (ISO)Symbol (ANSI)dropdown_mmdropdown_inchThickness (mm)Thickness (Inch)01101 (1.59 mm)1 (0.0625")1.590.0625021.502 (2.38 mm)1.5 (0.09375")2.380.093803203 (3.18 mm)2 (0.125")3.180.125004304 (4.76 mm)3 (0.1875")4.760.1875053.505 (5.56 mm)3.5 (0.21875")5.560.218806406 (6.35 mm)4 (0.25")6.350.250007507 (7.94 mm)5 (0.3125")7.940.312509609 (9.52 mm)6 (0.375")9.520.375012812 (12.7 mm)8 (0.5")12.700.5000T11.2T1 (1.98 mm)1.2 (0.078125")1.980.0781T32.5T3 (3.97 mm)2.5 (0.15625")3.970.1563Corner RadiusCNMG120408432ISO (Metric): The symbol is the corner radius in millimeters times 10.If the result is less than 10, a leading zero is added.ANSI (Inch): The symbol is 64 times the corner radius in inches.If the result is more than one, it is rounded to the nearest integer.If the result is less than one, it is rounded to the next 0.25 multiple.Symbol (ISO)Symbol (ANSI)Radius (mm)Radius (Inch)dropdown_mmdropdown_inch0000.00.000000 (0.0 mm)0 (0")010.250.10.004001 (0.1 mm)0.25 (0.004")020.50.20.008002 (0.2 mm)0.5 (0.008")0410.40.015604 (0.4 mm)1 (0.0156")0820.80.031308 (0.8 mm)2 (0.0313")1231.20.046912 (1.2 mm)3 (0.0469")1641.60.062516 (1.6 mm)4 (0.0625")2462.40.093824 (2.4 mm)6 (0.0938")3283.20.125032 (3.2 mm)8 (0.125")Popular Turning InsertsAlthough the possible combinations are endless, only a handful of them are practically offered by most of the cutting tool suppliers.The table below lists the typical offerings. While there are other inserts in the market not listed here, 90% of the offerings are included.(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts

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The tolerances defined in ISO 1382 are the “worst case” scenario that a manufacturer must comply with. Some premium manufacturers have stricter tolerances in their production to improve the quality and repeatability of their product line. However, they are unlikely to declare this formally.Additionally, the standard defines the tolerance only for 3 parameters:d – Inscribed circle diameter: The limit on the insert size.m – Cutting edge position: This is an important parameter since it defines the repeatability you can expect on the turned diameter when indexing a corner or replacing an insert.s – Insert thickness: Effect the reputability of the cutting edge height. It is an important parameter when machining small diameters.All the many other properties of a turning insert (Including the nose radius) are not defined, and each manufacturer has its own internal standard, which he usually does not make public.How to use the tolerance charts below?Although the chart includes 12 tolerance classes, only two are used in practice!M – For pressed inserts.G – For ground inserts.E – Very rarely used. It is the same as G but with striker thickness tolerance.The first chart provides the basic values. If a cell is empty, obtain the value from the second chart based on the insert’s shape and size.Main Tolerance ChartTolerance ClassTolerance of d(IC)Tolerance of m(Edge Position)Tolerance of s(Thickness)M (Pressed Inserts)See next table(According to size and shape)+/-0.013 mm0.0005"G (Ground Inserts)+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"E+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"A+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"F+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"C+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"H+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"J+/-0.013 mm0.0005"+/-0.013 mm0.0005"K+/-0.013 mm0.0005"+/-0.013 mm0.0005"L+/-0.013 mm0.0005"+/-0.013 mm0.0005"N+/-0.013 mm0.0005"U+/-0.013 mm0.0005"Complimentary Tolerance ChartShapeSize (IC)Tolerance on dTolerance on mD4 - 10 mm3/16-3/8"+/- 0.05 mm+/- 0.002"+/- 0.11 mm+/- 0.004"12.7 mm1/2"+/- 0.08 mm+/- 0.003"+/- 0.15mm+/- 0.006"15.87-19.055/8-3/4"+/- 0.1 mm+/- 0.004"+/- 0.18 mm+/- 0.007"VAny Size+/- 0.05 mm+/- 0.002"+/- 0.16 mm+/- 0.006"All other Shapes4 - 10 mm3/16-3/8"+/- 0.05 mm+/- 0.002"+/- 0.08 mm+/- 0.003"12.0-12.7 mm1/2"+/- 0.08 mm+/- 0.003"+/- 0.13 mm+/- 0.005"15.87-20 mm5/8-3/4"+/- 0.1 mm+/- 0.004"+/- 0.15mm+/- 0.006"25.0-25.4 mm1"+/- 0.13 mm+/- 0.005"+/- 0.18 mm+/- 0.007"31.75 - 32 mm1 1/4""+/- 0.15mm+/- 0.006"+/- 0.2 mm+/- 0.008"Configuration (Mounting style and Chip breaker)CNMG120408The fourth symbol (strangely) defines a combination of 2 unconnected properties:Mounting style: Describes how the insert can be clamped on the tool holder.Chip Breaker: Describes if a chip breaker exists and on which side of the insert. It does not say anything about its geometry.SymbolClamping MethodChip BreakerNegative InsertPositive InsertsGCylindrical fixing holeChip breakers on both facesMCylindrical fixing holeChip breakers on one face onlyACylindrical fixing holeWithout chip breakersTCylindrical fixing hole, with 40°-60° countersink on one sideChip breakers on one face onlyWCylindrical fixing hole, with 40°-60° countersink on one sideWithout chip breakersUCylindrical fixing hole, with 40°-60° countersinks on both sidesChip breakers on both facesQCylindrical fixing hole, with 40°-60° countersinks on both sidesWithout chip breakersHCylindrical fixing hole, with 70°-90° countersink on one sideChip breakers on one face onlyBCylindrical fixing hole, with 70°-90° countersink on one sideWithout chip breakersJCylindrical fixing hole, with 70°-90° countersinks on both sidesChip breakers on both facesCCylindrical fixing hole, with 70°-90° countersinks on both sidesWithout chip breakersFWithout a fixing holeChip breakers on both facesRWithout a fixing holeChip breakers on one face onlyNWithout a fixing holeWithout chip breakersXX - Special - Requires detailed explanation/drawingX - Special - Requires detailed explanation/drawingThere are 3 main mounting style options (Parameter code IFS that can equal 1, 2, or 3):1 – Without a fixing Hole: This option is used mainly on ceramic and full CBN inserts, where there is a technological problem with producing the insert with a hole or clamping it with the hole, which will break it.2 – Cylindrical hole: Used with “Lever-Lock” clamping mechanism. This method utilizes an L-shaped lever to clamp the insert against two walls of the insert pocket.Advantages:Quick and easy indexing.No falling parts.Disadvantages:It requires more space in the cutting tool to house the mechanism, thus making it less suitable for smaller holders and internal tools for small bore diameters.The force vector that pushes the insert down is small; therefore, it is less stable.To solve this problem, a top clamp is sometimes added; however, this removes some advantages.3 – Cylindrical hole with countersinks: The insert is clamped with a screw that secures the insert against two walls and also forces it downwards.Advantages:Very simple design and production.Takes minimum space in the cutting tool.Secures the inserts in 3 directions.Best for small and internal tools.Disadvantages:Slower indexing.Falling parts (Easy to lose the screw)SizeCNMG120408432The insert’s size symbol works differently in the ISO and ANSI conventions:ISOANSILength of cutting edgeShape’s inscribed circleEquals approximately the length (In mm)Equals approximately 8*IC (In Inches)Each shape has a different list of symbolsSame symbol for all shapesSize Symbol ChartFor ISO (Metric) size, check under the relevant shape symbolInscribed Circle DiameterANSI (Inch) Size SymbolISO (Metric) Size Symbol per Insert ShapemmInchSTCDEVWR3.970.156251.20306X04X0602X4.760.18751.5040804050408L3X5.560.218751.805090506050903X6.350.25206110607061104067.940.31252.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131mmInchANSISymbolSTCDEVWR3.970.1561.20306X04X0602X4.760.1871.5040804050408L3X5.560.2191.805090506050903X6.350.25206110607061104067.940.3132.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131Round Metric Inserts (With “M0” suffix)In the metric designation of round inserts (R Shape), it is possible to add the “M0” suffix (For example, RNMG 1204-M0).In such a case, the diameter is metric, and the table below should be used (Instead of the above)Pay attention! RNMG 1204 (or RNMG 120400) has a diameter of 12.7 mm, but RNMG 1204-M0 has a diameter of 12.0 mm!symbolDiameter066 mm (0,236″)088 mm (0,315″)1010 mm (0,394″)1212 mm (0,472″)1616 mm (0,63″)2020 mm (0,787″)2525 mm (0,984″)3232 mm (1,26″)ThicknessCNMG120408432The thickness is measured from the clamping (bottom) plane to the highest point of the cutting edge (Not the top plane). The symbol represents the thickness differently in metric and inch description formats:ISO (Metric): The symbol is approximately the thickness in millimeters.The first digit is always zero (See exception in the next bullet).When there are 2 nearby values (3.18 / 3.97), the zero is replaced by T for the larger one.ANSI (Inch): The symbol is 16 times the thickness (in inches)Symbol (ISO)Symbol (ANSI)dropdown_mmdropdown_inchThickness (mm)Thickness (Inch)01101 (1.59 mm)1 (0.0625")1.590.0625021.502 (2.38 mm)1.5 (0.09375")2.380.093803203 (3.18 mm)2 (0.125")3.180.125004304 (4.76 mm)3 (0.1875")4.760.1875053.505 (5.56 mm)3.5 (0.21875")5.560.218806406 (6.35 mm)4 (0.25")6.350.250007507 (7.94 mm)5 (0.3125")7.940.312509609 (9.52 mm)6 (0.375")9.520.375012812 (12.7 mm)8 (0.5")12.700.5000T11.2T1 (1.98 mm)1.2 (0.078125")1.980.0781T32.5T3 (3.97 mm)2.5 (0.15625")3.970.1563Corner RadiusCNMG120408432ISO (Metric): The symbol is the corner radius in millimeters times 10.If the result is less than 10, a leading zero is added.ANSI (Inch): The symbol is 64 times the corner radius in inches.If the result is more than one, it is rounded to the nearest integer.If the result is less than one, it is rounded to the next 0.25 multiple.Symbol (ISO)Symbol (ANSI)Radius (mm)Radius (Inch)dropdown_mmdropdown_inch0000.00.000000 (0.0 mm)0 (0")010.250.10.004001 (0.1 mm)0.25 (0.004")020.50.20.008002 (0.2 mm)0.5 (0.008")0410.40.015604 (0.4 mm)1 (0.0156")0820.80.031308 (0.8 mm)2 (0.0313")1231.20.046912 (1.2 mm)3 (0.0469")1641.60.062516 (1.6 mm)4 (0.0625")2462.40.093824 (2.4 mm)6 (0.0938")3283.20.125032 (3.2 mm)8 (0.125")Popular Turning InsertsAlthough the possible combinations are endless, only a handful of them are practically offered by most of the cutting tool suppliers.The table below lists the typical offerings. While there are other inserts in the market not listed here, 90% of the offerings are included.(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts

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Table of ContentsISO Inserts CalculatorISO Insert Charts & TheoryShapesClearance AnglesTolerancesConfigurationThicknessCorner RadiusPopular Turning Inserts

3 – Cylindrical hole with countersinks: The insert is clamped with a screw that secures the insert against two walls and also forces it downwards.

Like all drill bits, the auger bit bores a hole and ejects the chips. Meanwhile, the four sharp edges of the chisel pare the wood around the bored hole into a square shape. The auger bit removes this waste, as well, through a chip ejection slot in the chisel.

Although the possible combinations are endless, only a handful of them are practically offered by most of the cutting tool suppliers.The table below lists the typical offerings. While there are other inserts in the market not listed here, 90% of the offerings are included.(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts

The insert’s size symbol works differently in the ISO and ANSI conventions:ISOANSILength of cutting edgeShape’s inscribed circleEquals approximately the length (In mm)Equals approximately 8*IC (In Inches)Each shape has a different list of symbolsSame symbol for all shapesSize Symbol ChartFor ISO (Metric) size, check under the relevant shape symbolInscribed Circle DiameterANSI (Inch) Size SymbolISO (Metric) Size Symbol per Insert ShapemmInchSTCDEVWR3.970.156251.20306X04X0602X4.760.18751.5040804050408L3X5.560.218751.805090506050903X6.350.25206110607061104067.940.31252.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131mmInchANSISymbolSTCDEVWR3.970.1561.20306X04X0602X4.760.1871.5040804050408L3X5.560.2191.805090506050903X6.350.25206110607061104067.940.3132.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131Round Metric Inserts (With “M0” suffix)In the metric designation of round inserts (R Shape), it is possible to add the “M0” suffix (For example, RNMG 1204-M0).In such a case, the diameter is metric, and the table below should be used (Instead of the above)Pay attention! RNMG 1204 (or RNMG 120400) has a diameter of 12.7 mm, but RNMG 1204-M0 has a diameter of 12.0 mm!symbolDiameter066 mm (0,236″)088 mm (0,315″)1010 mm (0,394″)1212 mm (0,472″)1616 mm (0,63″)2020 mm (0,787″)2525 mm (0,984″)3232 mm (1,26″)ThicknessCNMG120408432The thickness is measured from the clamping (bottom) plane to the highest point of the cutting edge (Not the top plane). The symbol represents the thickness differently in metric and inch description formats:ISO (Metric): The symbol is approximately the thickness in millimeters.The first digit is always zero (See exception in the next bullet).When there are 2 nearby values (3.18 / 3.97), the zero is replaced by T for the larger one.ANSI (Inch): The symbol is 16 times the thickness (in inches)Symbol (ISO)Symbol (ANSI)dropdown_mmdropdown_inchThickness (mm)Thickness (Inch)01101 (1.59 mm)1 (0.0625")1.590.0625021.502 (2.38 mm)1.5 (0.09375")2.380.093803203 (3.18 mm)2 (0.125")3.180.125004304 (4.76 mm)3 (0.1875")4.760.1875053.505 (5.56 mm)3.5 (0.21875")5.560.218806406 (6.35 mm)4 (0.25")6.350.250007507 (7.94 mm)5 (0.3125")7.940.312509609 (9.52 mm)6 (0.375")9.520.375012812 (12.7 mm)8 (0.5")12.700.5000T11.2T1 (1.98 mm)1.2 (0.078125")1.980.0781T32.5T3 (3.97 mm)2.5 (0.15625")3.970.1563Corner RadiusCNMG120408432ISO (Metric): The symbol is the corner radius in millimeters times 10.If the result is less than 10, a leading zero is added.ANSI (Inch): The symbol is 64 times the corner radius in inches.If the result is more than one, it is rounded to the nearest integer.If the result is less than one, it is rounded to the next 0.25 multiple.Symbol (ISO)Symbol (ANSI)Radius (mm)Radius (Inch)dropdown_mmdropdown_inch0000.00.000000 (0.0 mm)0 (0")010.250.10.004001 (0.1 mm)0.25 (0.004")020.50.20.008002 (0.2 mm)0.5 (0.008")0410.40.015604 (0.4 mm)1 (0.0156")0820.80.031308 (0.8 mm)2 (0.0313")1231.20.046912 (1.2 mm)3 (0.0469")1641.60.062516 (1.6 mm)4 (0.0625")2462.40.093824 (2.4 mm)6 (0.0938")3283.20.125032 (3.2 mm)8 (0.125")Popular Turning InsertsAlthough the possible combinations are endless, only a handful of them are practically offered by most of the cutting tool suppliers.The table below lists the typical offerings. While there are other inserts in the market not listed here, 90% of the offerings are included.(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts

Advantages:Very simple design and production.Takes minimum space in the cutting tool.Secures the inserts in 3 directions.Best for small and internal tools.

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The designation of ISO inserts is described in ISO 1832 (and in ANSI B212.12.*). The full designation contains 13 symbols, of which only the first 7 are mandatory. Positions 8-13 are used to describe wiper, CBN, and PCD inserts fully. This page deals with positions 1-7 for both the Inch and Metric designations. For example, CNMG 120408, and CNMG 432.DesignDimensionsPosition1234567MeaningShapeClearanceToleranceConfigurationSizeThicknessRadiusExample (ISO)CNMG120408Example (ANSI)432PositionMeaningExample(ISO/ANSI)1ShapeC2ClearanceN3ToleranceM4ConfigurationG5Size12 /46Thickness04 / 37Radius08 /  2The designation of an ISO insert consists of 7 symbols. They are divided into 2 groups. The first 4 symbols form the “Design Group”, followed by 3 symbols that form the “Dimensions Group”.It is standard practice to include a space between the two groups of symbols. (e.g., CNMG 432)Design Group (4 Symbols):Each symbol consists of a single-letter code.The symbols are identical in the ISO and ANSI descriptions.They jointly describe the outline of the insert. Its shape, clearance angle, tolerance class, clamping method, and chip breaker presence.Dimensions Group (3 Symbols):This group differs for ISO (metric) and ANSI (Inch) standards.They jointly describe the basic dimensions of the insert— size, thickness, and corner radius.ISO:Each symbol consists of two digits.The size refers to the rib’s length.In most cases, the symbol hints at the value of the parameters.ANSI:Each symbol consists of one digit (90% of the cases).The size refers to the insert’s shape inscribed circle.In most cases, the relation between the symbol and the value of the parameter is unclear.ShapeCNMG120408The shape determines two main parameters. Nose angle and Cutting edge count (CEDC)A higher CEDC is always good since it is more economical (But it usually brings in other limitations).A larger nose angle means a stronger cutting-edge, which enables higher feed rates. But comes with the following negative effects:Increased cutting force.Increased vibration.Limited application flexibility.A smaller nose angle means more application flexibility and less vibrations but comes at the expense of a weaker cutting edge.sortSymbolFigureNose AngleShapeCEDCMainm Appliactions1C80°80° Rhombic2C is the most commonly used shape for general turning. It had a good balance between edge strength and application flexibility, making it an excellent first choice in many cases.2D55°55° Rhombic2D a is a popular choice when the 80° of the C-shape does not enable enough application flexibility to machine the needed geometry.3V35°35° Rhombic2V is the go-to choice when you need broad application flexibility or to reduce the cutting force in a finishing operation. (For example, turning a thin wall or a long shaft)6S90°Square4Square inserts feature very high edge strength and 4 cutting corners (Double than C). The downsides are high cutting forces and low application flexibility.7T60°Triangular3Triangular inserts have a compact size relative to the cutting-edge length. However, they have limited application flexibility and a relatively weak cutting edge.8W80°Trigon3The Trigon shape features the same cutting edge as the popular C shape. The advantage is more cutting edges (3 vs 2). However, the cutting edge is shorter, and the clamping quality is lower.9R360°Round6Round-shaped inserts feature the strongest possible edge and a large edge count but also exert the highest cutting force. They are mostly used in long roughing operations.10L90°Rectangular4L-shaped inserts are used in heavy-duty turning because they can take substantial depth of cuts.31K55°55° Parallelogram2The K shape is used only in KNUX inserts.32B82°82° Parallelogram2Very rarely used.33A85°85° Parallelogram2Not used in turning but a very popular milling shape.37E75°75° Rhombic2E is a rhombic shape insert that is rarely used (C, D, and V are the typical choices)38M86°86° Rhombic2M is a rhombic shape insert that is rarely used (C, D, and V are the typical choices)41P108°Pentagonal5Not used in turning but a very popular milling shape.42H120°Hexagonal6Not used in turning but a very popular milling shape.43O135°Octagonal8Not used in turning but a very popular milling shape.Clearance AngleCNMG120408The clearance angle (α / AN) refers to the angle between the “sides” of the insert and its clamping axis.An insert with a zero clearance angle (Symbol “N“) is nicknamed a “negative insert”.An insert with any other clearance angle is nicknamed a “positive insert”.Negative inserts provide:Double-sided inserts, hence a double edge count.Strongest possible cutting edge.The first choice for roughing and medium external turning.Positive inserts provide:Reduced cutting force (Less vibrations).Larger clearance between the insert and the workpiece.They can machine inside smaller bores in internal turning applications.A larger positive angle improves the above properties but reduces the edge strength.The first choice for finish operations (Internal/external) and for any internal turning operation inside smaller bore diameters.Clreannce Angle Symbols (From ISO 1832)SymbolClearance AngleA3°B5°C7°D15°E20°F25°G30°N0°P11°XAny other angleIn practice, only these 4 codes are used:N – Negative insert (0°) – For example, CNMG.C – Positive insert (7°) – For example, CCMT. 90% of the positive inserts on the markets have a 7° clearance angle.P – Positive insert (11°) – For example, TPMT. When a larger clearance is required. Mainly used in T-shaped inserts for internal turning.B – Positive insert (5°) – For example, WBGT. When a positive geometry is desired, but a stronger cutting edge is needed. It is mainly used on PCD/CBN tipped and small W-shaped inserts.TolerancesCNMG120408The tolerances defined in ISO 1382 are the “worst case” scenario that a manufacturer must comply with. Some premium manufacturers have stricter tolerances in their production to improve the quality and repeatability of their product line. However, they are unlikely to declare this formally.Additionally, the standard defines the tolerance only for 3 parameters:d – Inscribed circle diameter: The limit on the insert size.m – Cutting edge position: This is an important parameter since it defines the repeatability you can expect on the turned diameter when indexing a corner or replacing an insert.s – Insert thickness: Effect the reputability of the cutting edge height. It is an important parameter when machining small diameters.All the many other properties of a turning insert (Including the nose radius) are not defined, and each manufacturer has its own internal standard, which he usually does not make public.How to use the tolerance charts below?Although the chart includes 12 tolerance classes, only two are used in practice!M – For pressed inserts.G – For ground inserts.E – Very rarely used. It is the same as G but with striker thickness tolerance.The first chart provides the basic values. If a cell is empty, obtain the value from the second chart based on the insert’s shape and size.Main Tolerance ChartTolerance ClassTolerance of d(IC)Tolerance of m(Edge Position)Tolerance of s(Thickness)M (Pressed Inserts)See next table(According to size and shape)+/-0.013 mm0.0005"G (Ground Inserts)+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"E+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"A+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"F+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"C+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"H+/-0.013 mm0.0005"+/-0.013 mm0.0005"+/-0.013 mm0.0005"J+/-0.013 mm0.0005"+/-0.013 mm0.0005"K+/-0.013 mm0.0005"+/-0.013 mm0.0005"L+/-0.013 mm0.0005"+/-0.013 mm0.0005"N+/-0.013 mm0.0005"U+/-0.013 mm0.0005"Complimentary Tolerance ChartShapeSize (IC)Tolerance on dTolerance on mD4 - 10 mm3/16-3/8"+/- 0.05 mm+/- 0.002"+/- 0.11 mm+/- 0.004"12.7 mm1/2"+/- 0.08 mm+/- 0.003"+/- 0.15mm+/- 0.006"15.87-19.055/8-3/4"+/- 0.1 mm+/- 0.004"+/- 0.18 mm+/- 0.007"VAny Size+/- 0.05 mm+/- 0.002"+/- 0.16 mm+/- 0.006"All other Shapes4 - 10 mm3/16-3/8"+/- 0.05 mm+/- 0.002"+/- 0.08 mm+/- 0.003"12.0-12.7 mm1/2"+/- 0.08 mm+/- 0.003"+/- 0.13 mm+/- 0.005"15.87-20 mm5/8-3/4"+/- 0.1 mm+/- 0.004"+/- 0.15mm+/- 0.006"25.0-25.4 mm1"+/- 0.13 mm+/- 0.005"+/- 0.18 mm+/- 0.007"31.75 - 32 mm1 1/4""+/- 0.15mm+/- 0.006"+/- 0.2 mm+/- 0.008"Configuration (Mounting style and Chip breaker)CNMG120408The fourth symbol (strangely) defines a combination of 2 unconnected properties:Mounting style: Describes how the insert can be clamped on the tool holder.Chip Breaker: Describes if a chip breaker exists and on which side of the insert. It does not say anything about its geometry.SymbolClamping MethodChip BreakerNegative InsertPositive InsertsGCylindrical fixing holeChip breakers on both facesMCylindrical fixing holeChip breakers on one face onlyACylindrical fixing holeWithout chip breakersTCylindrical fixing hole, with 40°-60° countersink on one sideChip breakers on one face onlyWCylindrical fixing hole, with 40°-60° countersink on one sideWithout chip breakersUCylindrical fixing hole, with 40°-60° countersinks on both sidesChip breakers on both facesQCylindrical fixing hole, with 40°-60° countersinks on both sidesWithout chip breakersHCylindrical fixing hole, with 70°-90° countersink on one sideChip breakers on one face onlyBCylindrical fixing hole, with 70°-90° countersink on one sideWithout chip breakersJCylindrical fixing hole, with 70°-90° countersinks on both sidesChip breakers on both facesCCylindrical fixing hole, with 70°-90° countersinks on both sidesWithout chip breakersFWithout a fixing holeChip breakers on both facesRWithout a fixing holeChip breakers on one face onlyNWithout a fixing holeWithout chip breakersXX - Special - Requires detailed explanation/drawingX - Special - Requires detailed explanation/drawingThere are 3 main mounting style options (Parameter code IFS that can equal 1, 2, or 3):1 – Without a fixing Hole: This option is used mainly on ceramic and full CBN inserts, where there is a technological problem with producing the insert with a hole or clamping it with the hole, which will break it.2 – Cylindrical hole: Used with “Lever-Lock” clamping mechanism. This method utilizes an L-shaped lever to clamp the insert against two walls of the insert pocket.Advantages:Quick and easy indexing.No falling parts.Disadvantages:It requires more space in the cutting tool to house the mechanism, thus making it less suitable for smaller holders and internal tools for small bore diameters.The force vector that pushes the insert down is small; therefore, it is less stable.To solve this problem, a top clamp is sometimes added; however, this removes some advantages.3 – Cylindrical hole with countersinks: The insert is clamped with a screw that secures the insert against two walls and also forces it downwards.Advantages:Very simple design and production.Takes minimum space in the cutting tool.Secures the inserts in 3 directions.Best for small and internal tools.Disadvantages:Slower indexing.Falling parts (Easy to lose the screw)SizeCNMG120408432The insert’s size symbol works differently in the ISO and ANSI conventions:ISOANSILength of cutting edgeShape’s inscribed circleEquals approximately the length (In mm)Equals approximately 8*IC (In Inches)Each shape has a different list of symbolsSame symbol for all shapesSize Symbol ChartFor ISO (Metric) size, check under the relevant shape symbolInscribed Circle DiameterANSI (Inch) Size SymbolISO (Metric) Size Symbol per Insert ShapemmInchSTCDEVWR3.970.156251.20306X04X0602X4.760.18751.5040804050408L3X5.560.218751.805090506050903X6.350.25206110607061104067.940.31252.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131mmInchANSISymbolSTCDEVWR3.970.1561.20306X04X0602X4.760.1871.5040804050408L3X5.560.2191.805090506050903X6.350.25206110607061104067.940.3132.507130809081305079.5250.3753091609110916060912.70.54122212151322081215.8750.6255152716191627101519.050.756193319231933131925.418254425312644172531.751.25103154323832542131Round Metric Inserts (With “M0” suffix)In the metric designation of round inserts (R Shape), it is possible to add the “M0” suffix (For example, RNMG 1204-M0).In such a case, the diameter is metric, and the table below should be used (Instead of the above)Pay attention! RNMG 1204 (or RNMG 120400) has a diameter of 12.7 mm, but RNMG 1204-M0 has a diameter of 12.0 mm!symbolDiameter066 mm (0,236″)088 mm (0,315″)1010 mm (0,394″)1212 mm (0,472″)1616 mm (0,63″)2020 mm (0,787″)2525 mm (0,984″)3232 mm (1,26″)ThicknessCNMG120408432The thickness is measured from the clamping (bottom) plane to the highest point of the cutting edge (Not the top plane). The symbol represents the thickness differently in metric and inch description formats:ISO (Metric): The symbol is approximately the thickness in millimeters.The first digit is always zero (See exception in the next bullet).When there are 2 nearby values (3.18 / 3.97), the zero is replaced by T for the larger one.ANSI (Inch): The symbol is 16 times the thickness (in inches)Symbol (ISO)Symbol (ANSI)dropdown_mmdropdown_inchThickness (mm)Thickness (Inch)01101 (1.59 mm)1 (0.0625")1.590.0625021.502 (2.38 mm)1.5 (0.09375")2.380.093803203 (3.18 mm)2 (0.125")3.180.125004304 (4.76 mm)3 (0.1875")4.760.1875053.505 (5.56 mm)3.5 (0.21875")5.560.218806406 (6.35 mm)4 (0.25")6.350.250007507 (7.94 mm)5 (0.3125")7.940.312509609 (9.52 mm)6 (0.375")9.520.375012812 (12.7 mm)8 (0.5")12.700.5000T11.2T1 (1.98 mm)1.2 (0.078125")1.980.0781T32.5T3 (3.97 mm)2.5 (0.15625")3.970.1563Corner RadiusCNMG120408432ISO (Metric): The symbol is the corner radius in millimeters times 10.If the result is less than 10, a leading zero is added.ANSI (Inch): The symbol is 64 times the corner radius in inches.If the result is more than one, it is rounded to the nearest integer.If the result is less than one, it is rounded to the next 0.25 multiple.Symbol (ISO)Symbol (ANSI)Radius (mm)Radius (Inch)dropdown_mmdropdown_inch0000.00.000000 (0.0 mm)0 (0")010.250.10.004001 (0.1 mm)0.25 (0.004")020.50.20.008002 (0.2 mm)0.5 (0.008")0410.40.015604 (0.4 mm)1 (0.0156")0820.80.031308 (0.8 mm)2 (0.0313")1231.20.046912 (1.2 mm)3 (0.0469")1641.60.062516 (1.6 mm)4 (0.0625")2462.40.093824 (2.4 mm)6 (0.0938")3283.20.125032 (3.2 mm)8 (0.125")Popular Turning InsertsAlthough the possible combinations are endless, only a handful of them are practically offered by most of the cutting tool suppliers.The table below lists the typical offerings. While there are other inserts in the market not listed here, 90% of the offerings are included.(*) Click an insert to get the complete information about itInsert FamiliyDescriptionCCGT80° rhombic ground and postivide inserts for finishining operationsCCMT80° rhombic postivide inserts for semi-finish and finish operationsCNMA80° rhombic negative inserts with flat top & bottom for machining short chippling materialsCNMG80° rhombic double sided inserts for general turningCNMM80° rhombic single sided inserts for heavy duty applicationsDCGT55° rhombic ground and postivide inserts for finishining operationsDCMT55° rhombic postivide inserts for semi-finish and finish operationsDNMG55° rhombic double sided inserts for general turningSCMTSqaure postivide inserts for semi-finish and finish operationsSNMASquare negative inserts with flat top & bottom for machining short chippling materialsSNMGSquare double sided inserts for general turningSNMMSquare single sided inserts for heavy duty applicationsTCGTTriangular ground and postivide inserts for finishining operationsTCMTTriangular postivide inserts for semi-finish and finish operationsTNMATriangular inserts with flat top & bottom for machining short chippling materialsTNMGTriangular double sided inserts for general turningTMPTTriangular supper-postivide inserts for internal turining in small diametersVBGT35° rhombic ground and postivide small-size inserts for super-finish operationsVBMT35° rhombic postivide small-size inserts for finishining operationsVCGT35° rhombic ground and postivide inserts for supper-finishining operationsVCMT35° rhombic postivide inserts for finishining operationsVNGG35° rhombic double sided and ground inserts for general turningVNMG35° rhombic double sided inserts for general turningWNMGTrigon double sided inserts for general turningRelated Glossary Terms:CBN InsertsPCD InsertsTolerance ClassCutting EdgeTurningMillingCeramic Inserts