All tools require cutter radius compensation

Although centerline programming is a very convenient method for program development, it is also a method unacceptable for machining. During contact with material, the cutting tool edge must be in contact with the programmed part contour — not its centerline. Actual toolpath for all contouring operations is always equivalent to the cutting tool motion.

Whether used on a CNC machining center or on a CNC lathe, the cutting tool edge must always be tangent to the contour, which means the tool motion has to create a path where the center point of the cutter is always at the same distance from the contour of the part. This is called the equidistant tool path. The illustration in Figure shows two types of a tool path.

One is not compensated, the other is compensated. Both are applied to a particular contour, with the cutter diameter shown as well, including its positions. In order to program one or the other mode of cutting based on cutting direction , control systems offer two preparatory commands to select the desired cutter radius offset direction mode.

Keeping in mind that the terms climb and conventional refer to milling only and are relative to spindle rotation and the hand of milling cutter. By this definition, the G41 command is applied for climb milling mode, G42 command is applied for conventional milling mode: The table shows all relationships between tool type, tool rotation, and cutting direction. There is no cutter radius offset applied when G40 command is in effect. What is tool offset and work offset?

What is workpiece Zeropoint? What does H mean in G code? G codes for tool length compensation. What is G code and M code? What is nose radius? What is g43 in CNC code? What is meant by cutter radius compensation? What is the tool length offset? What is Tool length compensation? What is tool type in CNC? How do you calculate tool nose radius? Using the formula above lets calculate the X compensation:.

Tool Radius. How do I use code g54? What is canned cycle in CNC programming? How g41 and g42 turn in CNC? What is the correct code for canceling cutter compensation? What is Climb milling? What is a g50? I recommend plotting the coordinates from your program on a piece of graph paper. Using a circle the same size as your cutter, try moving the circle around the plotted path to see if the circle can move around all surfaces.

For each contour to be machined, you must instate, cut with and cancel cutter radius compensation. If you must rapid the tool to another surface, it should be taken as a signal that you must cancel cutter radius compensation and then reinstate it on the next surface.

However, if no alarms are generated, you could be in for a nasty surprise. Say for example, that the tool following the milling cutter using cutter radius compensation is a drill. The drill will machine its holes out of position by the amount stored in the cutter radius compensation offset register. It may take some time before it occurs to you to check whether cutter radius compensation is being canceled. Again, cutter radius compensation can be difficult to fully master.

Given the benefits of cutter radius compensation , be sure to stick with it until you fully understand it. Creating threaded holes in titanium alloys calls for proper techniques based on an understanding of both the properties of these materials and the peculiarities of the tapping process. Running rotary milling cutters at the proper speeds and feeds is critical to obtaining long tool life and superior results, and a good place to start is with the manufacturer's recommendations. These formulas and tips provide useful guidelines.

Insufficient Clearance on Approach Almost all versions of cutter radius compensation require that you make a prior position movement in X and Y to get the tool to a position from which tool length compensation can be instated.