Igor Chudov wrote: > I have a vertical mill with a fourth axis A. > > My buddy wants me to write a subroutine that would let me mill thread on > round parts, that are held in the fourth axis, and the thread would be > milled using a 60 degree chamfer end mill, rotating the part around the A > axis. > > I'm a little confused by this. The A axis is traditionally parallel to the X axis, so the part rotates parallel to the table. While a 60 degree angle cutter would produce a geometrically accurate thread, it may not be the best way to machine a thread. Having the rotation axis of the cutter parallel (but offset) from the rotation of the part to be threaded produces cutter motion past the work on every part of the thread profile, while the way you seem to be describing, with the point of the cutter in the bottom of the thread groove does not. > I have some questions about the odds and ends of this. > > 1. I would like to be able to say to the machine, in G code, that "wherever > we are on the A axis, call it zero degrees position". In other words, I > want to change the coordinate system in G code for one A axis only. How do > I do it. > Just home the A axis and that will be zero. Or, "touch off" the A axis. > 2. Is that correct that feedrate F in a G1 statement that changes both X, > as well as A, only refers to the change of X? I can live with that, I just > want to know. Yes, that is so. If your X is the length of the thread along the axis of rotation, then the specified feedrate will be WAY off, so you'll have to compensate for the number of turns around the diameter.
I have a program for more conventional thread milling that can be downloaded from http://pico-systems.com/gcode.html (it is near the bottom of the page). Jon ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_d2d_mar _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
