Embedded answer On Sun, Jun 7, 2020, 12:32 PM andy pugh <bodge...@gmail.com> wrote:
> On Sun, 7 Jun 2020 at 17:58, Stuart Stevenson <stus...@gmail.com> wrote > > > > > If you are tilting the head of a knee mill (ie BridgePort style) you > would > > be rotating the A or B axis. > > > > Yes, I mean B axis. I have been thinking B-axis all along, but for some > reason typed C. > > > > You would then be able to jog the theoretical A and/or B axes to match > the > > head orientation and machine features orthogonal to the tool axis using U > > and V. > > > > Which would be useful if LinuxCNC could do UV arcs, but I don't think it > does. > "The axis of the circle or helix must be parallel to the X, Y, or Z axis of > the machine coordinate system. The axis (or, equivalently, the plane > perpendicular to the axis) is selected with G17 (Z-axis, XY-plane), > G18 (Y-axis, > XZ-plane), or G19 (X-axis, YZ-plane). Planes 17.1, 18.1, and 19.1 are not > currently supported. If the arc is circular, it lies in a plane parallel to > the selected plane." > > I believe you would need to use tool lengths and a pivot point to have the > > display show tool positions relative to other features machined while > the A > > and B axes were orthogonal to the XY plane. > > > > I was planning to set up the tool lengths to be relative to the centre of > rotation of the head. > But I suspect that to make that work I would have to move all my > tool-lengths in to the W column, as ordinarily the Z length is simply added > to the Z axis position with no consideration of kinematics. > Are the tool lengths you use an actual tool length or a distance from machine zero. > > -- > atp > "A motorcycle is a bicycle with a pandemonium attachment and is designed > for the especial use of mechanical geniuses, daredevils and lunatics." > — George Fitch, Atlanta Constitution Newspaper, 1912 > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users