Operator`s manual

Advanced Haas Mill Programming Techniques Training Manual Page 18
Cutter Radius Compensation Sizing
Cutter radius compensation allows the programmer to forget about the radius of the tool and essentially
program the features on the print. The computer inside the controls figures which coordinate values need
to be changed to reflect the radius of the cutter. The following command turns cutter compensation on:
G41 X.0 D1.
The D value is stored in the Tool Offset page under the D column for each tool. G41 command is cutter
compensation left, G42 command is cutter compensation right. Most applications on CNC mills use G41
which is climb cutting. It gives better finish and tool life than G42 cutter compensation right. G42 is used
for conventional cutting.
Cutter compensation not only compensates tool location for the radius of the tool it also may be used for
sizing or dimensional control. The following illustration shows a ½ inch cutter cutting off the end of a part to
take it to size. If cutter compensation was not used the only way to size the 4.000 length was to change
the stop location on the left side of the part or edit the program.
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Using cutter compensation all that needs to be changed is the size of the radius or diameter value in the D
value of the Tool Offset screen. If the D value is smaller the machine will compensate by taking more
material off when it cuts. If the D value is larger the machine will move further away from the cutting edge
therefore leaving more material on.
D values on Haas Controls may be designated as diameters or radii in setting #40. For example the first
part is cut and the part measures 4.020”. .020” more material needs to be taken of the end of the part to
take it to the nominal dimension of 4.000. If the Haas machine is set up where D is radial value a negative (
-.020) would be added in the D Wear column. If the machine is set up in diameter mode two times the
value needs to added in the D column or (-.040). Just the opposite if more material needs to be left.
Positive values are added to the D value.