N13 = Switches back to G90 Absolute positioning I-0.5 J0 Z0.125 L5 (Thread cut, repeat 5 times) O60025 (G03 SNGL PNT THREAD MILL 1.5-8 UNC) N11 = Arcs out of thread, ramps up 1/8 pitch
N10 = Cuts full thread, Z moving up by the pitch value N9 = Arcs into thread, ramps up by 1/8 pitch G00 Z0.1 M09 (Rapid retract, Coolant off) (Z moving up by the pitch value to Z-0.375) (G54 X0 Y0 is at the center of the bore) Thread Milling ExampleThread Milling Example, 1.5 Diameter X 8 TPI: Tool Path, Turn on and off cutter compensation. This move will be the maximum compensation amount that you can adjust. You must program a linear move, either in the X or Y Axis, to move the tool to and from the diameter to cut. You cannot turn cutter compensation off or on during an arc movement. of the circle and turn off cutter compensation. The last step is to move away from the I.D. The next step is to program a complete circle ( G02 or G03) with a Z-Axis command of the amount of one full pitch of the thread (this is called Helical Interpolation). of the part.Īfter the initial positioning, the next step of the program is to turn on cutter compensation and move to the I.D. The result (.375) is the distance the cutter starts from the I.D. To start, take the hole diameter (1.500). thread mills a 1.5 diameter x 8 TPI hole with a 0.750" diameter x 1.0" thread hob. PITCH = 1/Threads per inch (Example - 1.0 divided by 8 TPI =. right hand thread will move down in the Z-Axis by the amount of one thread pitch. right hand thread will move up in the Z-Axis by the amount of one thread pitch. Internal holes smaller than 3/8 inch may not be possible or practical. (generates 1-inch radius for 20-pitch thread) To cut a full circle, do not specify an ending point ( X, Y, and Z ) program I, J, or K to define the center of the circle. To cut a full circle the I, J, K addresses must be used using an R address will not work. If the X, Y, and Z location for the selected plane is not specified, the endpoint of the arc is the same as the starting point for that axis.
The X, Y, and Z commands specify the end point of the arc. Only the I, J, or K specific to the selected plane are allowed ( G17 uses IJ, G18 uses IK and G19 uses JK).
In other words, the I, J, K addresses are the distances from the starting point to the center of the circle. I, J and K address are used to locate the arc center in relation to the start point. There are two methods of commanding a G02 or G03, the first is using the I, J, K addresses and the second is using the R address. Two axes are necessary to complete circular motion and the correct plane, G17- G19, must be used. These G codes are used to specify circular motion. I, J and K is the preferred method to program a radius.