There is an example on the forum of a simple component that corrects for a non-square machine (adjusts Y based on X position). Might help get you going. https://forum.linuxcnc.org/10-advanced-configuration/34031-using-hal-to-correct-axis-errors?start=0
Andy also links to a kinematics module to do the same thing in that thread.... Rod Webster *1300 896 832* +61 435 765 611 Vehicle Modifications Network www.vehiclemods.net.au On Mon, 25 Nov 2019 at 10:48, Stuart Stevenson <stus...@gmail.com> wrote: > A two (or three) dimension comp file could work wonders to straighten the > motion. To be able to correct Y and Z motion per X motion at the same > discreet points chosen for the bidirectional compensation would be a very > good thing. Correcting X and Z for Y motion and correcting X and Y for Z > motion would complete the package. > The interpolation for the correction values would make a machine motion > much straighter. > > This would not perfect the machine as lead screw lost motion and gib/linear > (guide ways) slop would still be present until mechanically corrected. > > A slight warp in the bed of a lathe would be easily corrected. > > thanks > Stuart > > > On Sun, Nov 24, 2019 at 4:08 PM Gene Heskett <ghesk...@shentel.net> wrote: > > > Greetings all; > > > > I see in Documentation.pdf at about page 375 its mentioned that if a comp > > file is used. then backlash is ignored. That seems a bit odd, until one > > realizes that COMP in this case is being used to correct for possible > > non-linearities in THAT screw. That detail could be clarified, but I've > > no suggestions how. > > > > What I am doing in the Sheldon, is compensating X based on Z position, so > > that it turns relatively straight in spite of a few thou of bed wear. > > IOW a different critter entirely. It also took several days to measure > > with a rifle bore sighting laser since it turned out to be temperature > > sensitive. For final readings I loosened the foot ball joint and left it > > loose for several days before snugging it back up. That seemed to have > > helped stabilize the measured error. > > > > Cheers, Gene Heskett > > -- > > "There are four boxes to be used in defense of liberty: > > soap, ballot, jury, and ammo. Please use in that order." > > -Ed Howdershelt (Author) > > If we desire respect for the law, we must first make the law respectable. > > - Louis D. Brandeis > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > _______________________________________________ > > Emc-developers mailing list > > Emc-developers@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-developers > > > > > -- > Addressee is the intended audience. > If you are not the addressee then my consent is not given for you to read > this email furthermore it is my wish you would close this without saving or > reading, and cease and desist from saving or opening my private > correspondence. > Thank you for honoring my wish. > > _______________________________________________ > Emc-developers mailing list > Emc-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-developers > _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
