On Monday 22 September 2014 22:03:55 Juergen Gnoss did opine And Gene did reply: > I have a strange behaviour on the following Inkscape gcodetools created > G-code the g-code is here > http://pastebin.com/wFYYUJRa > > not sure if it is on start or end of arcs > the y axis has a hick-up > ends up that I get a -3mm offset in Y > I use 2.6.3 from tghe last install ISO > > I have tested my stepper drivers and machine with > g-code running several axis together results in positioning is OK > > Anyone has a hint what I can test to find where the hick-up comes from
I have run that code several times in the latest 2.7.0 sim mode, and according to the backplot I believe it to be doing exactly what was wanted. That leaves machine accel and speed limits being exceeded, I suspect in the y axis only. 2 things to check first, one, that the G0 moves are not being commanded at a rate faster than the machine can accelerate, so in the .ini file, reduce the default speeds and acceleration settings to half what they are now to see if the problem does away. I would also check the step timings in that .ini file against what the wiki page says your drives need. There, longer doesn't generally hurt, but less can eat your lunch. Some gecko's seem to get slower with age, so if they do look ok, set then for about 1.5 times what the table shows & see if it effects the error. It should not. If it does, either leave it set long or have the gecko fixed. A third and forth but slim chance might be slow opto's in the breakout board, or puny drivers in your parport. A fifth possibility is the psu voltage drops enough when 2 axis's are brought up to speed at the same time, a theory that can be checked by breaking the G0 Z#up G0 X# Y# type moves into G0 X# G0 Y# Those timing tables are at: <http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Stepper_Drive_Timing> 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) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ Meet PCI DSS 3.0 Compliance Requirements with EventLog Analyzer Achieve PCI DSS 3.0 Compliant Status with Out-of-the-box PCI DSS Reports Are you Audit-Ready for PCI DSS 3.0 Compliance? Download White paper Comply to PCI DSS 3.0 Requirement 10 and 11.5 with EventLog Analyzer http://pubads.g.doubleclick.net/gampad/clk?id=154622311&iu=/4140/ostg.clktrk _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
