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Issue with g3 command incremental
« on: October 05, 2010, 12:18:22 PM »
Hi all,

There seems to be a problem with handling the attached gcode at line 245.
This should create a rather huge arc (outline of a ski btw). What happens is that the x-gauge counts correctly (you see the value continously properly counting up)
but the x-axis does not move. Distance mode = Abs, IJ Mode = Inc.

guess it might come from this high value of J...but this should not be an issue

thanks for any help
Re: Issue with g3 command incremental
« Reply #1 on: October 05, 2010, 01:17:08 PM »
Here is the command that causes the issue:

G1 X-86.0442 Y135.4873
G3 X-86.2276 I-0.092 J-2.9986
G2 X-1462.342 Y141.4518 I-602.4365 J19757.2383
G3 X-1462.4945 Y141.4538 I-0.1174 J-2.9977
G1 X-1476.228 Y141.2933

It is the third line.
As said, x DRO is counting, x Axis does not move.

Offline Hood

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Re: Issue with g3 command incremental
« Reply #2 on: October 05, 2010, 03:36:32 PM »
Just tried it  here and it seems to be working fine, the DRO moves and also I put the scope on my X Step pin and I get a nice pulse.
If you attach your xml I will see if its different with your settings.
Hood
Re: Issue with g3 command incremental
« Reply #3 on: October 06, 2010, 10:38:18 AM »
Sorry, but it took me a while to get to the machine.
Here you go with the file

Offline Hood

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Re: Issue with g3 command incremental
« Reply #4 on: October 06, 2010, 10:50:46 AM »
Will check it out when I get home tonight as I dont have a PP breakout cable here for scoping.
Hood

Offline Graham Waterworth

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Re: Issue with g3 command incremental
« Reply #5 on: October 06, 2010, 12:26:44 PM »
Will you please try this code and let us know the result. Just replace your 5 lines with these 5 lines.

G01 X-86.044 Y135.487
G03 X-86.228 R3.
G02 X-1462.342 Y141.452 R19766.421
G03 X-1462.495 Y141.454 R3.
G01 X-1476.228 Y141.293

Graham
Without engineers the world stops

Offline Hood

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Re: Issue with g3 command incremental
« Reply #6 on: October 06, 2010, 02:36:27 PM »
Weird thing is I cant load your code with your xml, get "radius to end of arc differs..........." errors, yet I can load it fine with my xml. Not figured out why yet but will keep looking.
Hood

Edit, found the problem, your xml had Inc distance mode  in General Config but why the code didnt change it I am not sure, anyway its loaded now, will go scope and see.
« Last Edit: October 06, 2010, 02:40:25 PM by Hood »

Offline Hood

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Re: Issue with g3 command incremental
« Reply #7 on: October 06, 2010, 02:48:38 PM »
Definitely working fine here now I changed General Config to Abs for Distance mode, getting pulse on X for that arc so your motor should be moving.
Hood
Re: Issue with g3 command incremental
« Reply #8 on: October 07, 2010, 02:26:12 AM »
Hm...i was playing around with IJ and Distance mode setting, because I thought the issue comes from them.
I was also changing these settings in my cam-software, to figure out if the issue is caused by the cam sw or by MACH at first.
Changing the settings in MACH seems to have immediate effect. But anyway ... none of the options was working.
Propably I forgot to save the setting last time I shut down MACH.
I will make sure to take the file I posted and set DistanceMode to Abs and IJ to Inc. But if I remember correctly, this is default, which was my first try.

I am currently running version .29 of MACH, and will try to move to .42 today.
Will let you know asap. Great help from your side btw :-)
Re: Issue with g3 command incremental
« Reply #9 on: October 15, 2010, 09:55:37 AM »
Sorry, took me a while as I was travelling.
The IJ and distance mode are the same as yours.
I let my cam sw create the nc file also in "convert to points" method, to have the option to mill w and w/o G2/3s.
I also went to the newest version of MACH.
My x axis speed is set to 750mm/min. When I use the arrow buttons on my keyboard the axis moves at 750, sometimes a little (745+-) slower.
I can drive it manually all over the place with no issues. Y axis is set to 400 or so, no issues here too.
Now I am loading the file I posted (with g3 and 450mm feed rate). It happens always at the same command: X-axis DRO is counting, axis does not move. When I touch the motors, I can feel IT SEEMS TO GET PULSES !!
Now I hit ESC. Machine stops. I reset emergency and can (arrow-keys) move x with 750, y with 400, no problem.
I even can, and that's crazy, take another file which mills a circle (G's !!!" at the same machine position at the same speed. No problem.
Now I take the "no G2/3"-file. Program runs...machine gets stuck close to the same position where it hangs up with the G3 file.
When I am forcing the feedrate down to 160mm...no problem....except time :-(

Processor is a 1.6GHz ATOM, XP with absolutely anyting else turned off.