Instead, do it on the block after leaving the contour.Īlso, there is another complication hidden here.

Therefore, do not cancel the radius compensation on the leaving block as it will confuse the compensation to go outside the pocket. Leaving the contour from the inside is slightly trickier than from the outside as we must take care not to cut outside the corner, and at the same time finish it off correctly. Then we approach position one and activate the compensation with G42 (right side this time). This means that we should position the tool at X40 Y40 to not break rule three (X/Y + tool diameter) and go down to our milling depth. Let us this time say that position 1 is located at X30 Y30 and that the square has sides 70x70.

Please note that when you are going to mill a pocket contour, you will have to approach the pocket from the inside. G00 G40 Z40 (Go straight up and deactivate) The approaching distance and the leaving distance should not be shorter than the tool diameter.Įxample program of a simple square using the three rules: To activate it, we need to do an XY-movement with G01. Please note that we can only cancel radius compensation on traverses in Z. This should be written as:Īlternatively, we can leave the contour by going straight up in Z. Cancel it with G40 and reactivate it again when you approach another contour.Īt the red arrow, we leave the contour. Do not keep the compensation on when a contour is ready. G40 must be used to cancel the compensation when a contour is done and the mill leaves the contour, either by leaving in XY or in Z. This is because the tool will stop before the programmed position (depending on the tool radius). The real movement will not be to X50 and Y50. This will activate left-side compensation. Then the approaching block would look like this: In this case, let us say that position 1 (lower-left corner of the square) is located in X50 Y50. G41 (left side compensation) and G42 (right side compensation) should be used on the first G01 transportation in XY that is used to approach the contour that is about to be milled. Here we will explain how to use the G40, G41, and G42 codes in CNC Simulator Pro. Radius compensation works similarly in most CNC machines, but there are differences in how to use the syntax and when to activate/ deactivate the compensation, etc.

Cnc simulator pro tutorial 2