Gene, This is a lathe I am talking about. So FWD is relative to the tools then? My tools can go in the turret (which is above and to the left of the spindle) in either direction (forward facing or rear facing). So these terms don’t define M3/M4….
Also, this is not a Chinese VFD. It is an Automation Direct model and I haven’’t ever had a problem commanding it to do the right thing before. It is interesting that you say there might be bugs in G96. We use it all the time and we do have some other oddities on this machine from time to time that I am now wondering could be related to that if it is indeed the case…. Anyone else know of bugs in G96? Thanks, -Tom > On Jul 25, 2019, at 1:38 PM, Gene Heskett <ghesk...@shentel.net> wrote: > > On Thursday 25 July 2019 12:33:31 tom-...@bgp.nu <mailto:tom-...@bgp.nu> > wrote: > >> Is there a standard or convention on which way M3 and M4 spins a lathe >> spindle? Is the direction (CW/CCW) viewed from looking at the spindle >> face or out FROM the spindle? > > M3 is fwd, so the tool cuts normally, m4 is reverse, so the tool will > slide without cutting if not pushed too hard. > > If reliable ground connection to the tool can be maintained, you can turn > slow in reverse while executing a G38.2 to get a relative LO offset with > an insulated workpiece connected to the motion.probe-input in .hal. I've > used small pieces of dbl-sided pcb, glued to a fixture, and some more > math to do that, and have around .0005" accuracy without leaving a mark > on the pcb top face. > >> Does it change depending on where the >> tools are? > > Look at it from the top of the spindle, CW is FWD. > >> I think I may have our lathe set up to spin opposite of >> convention but now I am not sure what that convention (standard?) >> is... >> >> But the real issue I am sending this email about is I have some gcode >> that Fusion 360 generated and a strange thing is happening with it on >> my Emco lathe running 2.7.14. >> >> What is happening is that after the PROFILE1 section runs, the spindle >> will sometimes change direction when going to do the CHAMFER2 section >> of code. I say sometime because I ran 6 or so of these parts and it >> ran fine, then suddenly it decided to change directions. I have also >> had the spindle stop entirely at this point. But Linuxcnc clearly >> thought it was still spinning and was going to happily jam the tool in >> there. The stopping has only happened once or twice in the 40 or so >> times I have run the program. The spinning in the opposite direction >> happens more frequently, maybe 4 times in 40 runs or so. > > My relatively un-educated guess is that you are dealing with something > that has a builtin Chinese VFD. No one on this side of the big pond has > figured out how to run one of those in the direction its been told to, > so my 6040 gantry now has a clone ebay src'd vfd that Just Works. Along > with all new (to it) drivers, because the psu supplied was totally > inedequate, a 24 volt unit that folded back to around 13 volts under > load. Now it moves xy at 200 ipm, and z at 30+, spindle motor is heavy > and all motors are best described as puny. > > The clone VFD runs it properly in both directions although the vfd had to > be tweaked to get any low speed torque. > >> The spindle codes are the same in both PROFILE1 and CHAMFER2 sections: >> G96 D3000 S500 M03. If I remove the G96 D3000 S500 M03 from the >> CHAMFER2 section of code I believe the problem goes away. I still >> need to run more to verify that but I am pretty sure that’s the case. >> >> Any ideas on what might be happening or how to debug it? I can of >> course just leave out the second G96 D3000 S500 M03 assuming that >> prevents it from happening, but I’d like to post-n-go as it were with >> Fusion code rather than have to bandaid. >> > While I can't say as I'd argue, but I think there may be bugs in G96 when > its running on more than a 2 axis machine. Last I heard it was being > looked at. CSS was intended, I think, to be used only on lathes. > > It doesn't bother me to remove an errant line of g-code. Other than that > which someone has supplied, the only machine generated code I've run > here came from eagle->pcb2gcode. I write everything else. But I write > loops that are not ever unrolled, so its not unusual that a 90 line file > might take 3 days to run. But most of my stuff runs in half an hour or > so. > >> The gcode file is: >> >> >> % >> (PROGRAM NAME--SA232) >> (PROGRAM COMMENT--SA-232_PLUG) >> (NOTE--OVERRIDING TOOL SPINDLE DIRECTION FOR TOOLS T1, T3, T5, AND T7) >> (POST--EMCOTURN 120P BASED ON GENERIC TORMACH TURNING) >> M70 (save modal state, restore at end) >> G7 >> G18 >> G90 >> G20 >> (GENERATED--THU JUL 25 160944 2019) >> (USERNAME--TOM) >> (FILE NAME--SA-232_LCH-1250-18 V12) >> (JOB--SETUP2) >> >> (FACE1) >> G53 G0 X0 >> G53 G0 Z0 >> M6 T0005 G43 H0005 >> G54 >> G96 D3000 S300 M03 >> G94 >> G90 G0 X1.5 Z0.1969 >> G0 Z0.0516 >> X1.4 >> G1 X1.1131 F10. >> X1. Z-0.005 >> X-0.0312 F5. >> X0.0819 Z0.0516 F20. >> G0 X1.5 >> Z0.1969 >> M05 >> M09 >> >> (PROFILE1) >> G96 D3000 S500 M03 >> G94 >> G0 X1.5 Z0.1969 >> Z0.0566 >> X1.0929 >> G1 X1.0531 F20. >> X0.94 Z0. F10. >> Z-0.4156 >> X1. >> X1.16 F20. >> G0 Z0.0566 >> X0.9931 >> G1 X0.88 Z0. F10. >> Z-0.4156 >> X0.94 >> X1.0531 Z-0.3591 F20. >> G0 Z0.0566 >> X0.9331 >> G1 X0.82 Z0. F10. >> Z-0.295 >> X0.845 Z-0.3075 >> G18 G3 X0.86 Z-0.3256 R0.0256 >> G1 Z-0.4156 >> X0.88 >> X0.9931 Z-0.3591 F20. >> G0 Z0.0566 >> X0.9005 >> G1 X0.7873 Z0. F10. >> Z-0.2787 >> X0.845 Z-0.3075 >> G3 X0.85 Z-0.3104 R0.0256 >> G1 X0.9631 Z-0.2538 F20. >> G0 Z0.0566 >> X0.8682 >> G1 X0.8678 F20. >> X0.7547 Z0. F10. >> G3 X0.7653 Z-0.0156 R0.0256 >> G1 Z-0.2677 >> X0.8173 Z-0.2937 >> X0.9305 Z-0.2371 F20. >> G0 Z0.0566 >> X0.8394 >> G1 X0.8273 F20. >> X0.7141 Z0. F10. >> G3 X0.7453 Z-0.0156 R0.0156 >> G1 Z-0.2718 >> X0.8308 Z-0.3146 >> G3 X0.84 Z-0.3256 R0.0156 >> G1 Z-0.4156 >> X0.9531 Z-0.3591 F20. >> X1. >> G0 X1.5 >> Z0.1969 >> M05 >> M09 >> >> (CHAMFER2) >> G96 D3000 S500 M03 >> G94 >> G0 Z0.1969 >> X1.5 >> Z0.0283 >> G1 X0.5996 F10. >> Z0.0237 >> X0.7927 Z-0.0729 >> G0 X1.5 >> Z0.1969 >> M05 >> M09 >> >> (THREAD1) >> M01 >> G53 G0 X0 >> G53 G0 Z0 >> M6 T0003 G43 H0003 >> M08 >> G97 S280 M04 >> G95 >> G0 X1.5 Z0.1969 >> G0 Z0.1406 >> G17 >> G76 P0.0625 Z-0.24 I-0.7547 J0.0328 K0.0868 R2. Q30. H1 >> G0 X1.5 Z0.1969 >> M05 >> M09 >> >> (PART1) >> M01 >> G53 G0 X0 >> G53 G0 Z0 >> M6 T0007 G43 H0007 >> M09 >> G96 D3000 S150 M03 >> G94 >> G0 X1.5 Z0.1969 >> G0 Z-0.4587 >> G1 X-0.016 F0.75 >> X1.5 >> G0 Z0.1969 >> M05 >> M09 >> >> M72 (restore modal state, was saved via M70 at start) >> M30 >> % >> >> >> >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users > > > 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 > <http://geneslinuxbox.net:6309/gene>> > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net <mailto:Emc-users@lists.sourceforge.net> > https://lists.sourceforge.net/lists/listinfo/emc-users > <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
