2010/8/19 Chris Radek <ch...@timeguy.com>: > > Yes, the problem is just what the error message says. There is a move > that makes a concave corner but the move cannot be reached (the tool > cannot move alongside it as you request) without gouging into the > profile of the part. Here is a screenshot showing the situation. I > copied your code, added g21 and g42 commands, and put a 1.1mm tool in > my tool table. I jogged the tool near the corner so you can see the > situtation. The highlighted cyan line is from line 7 in my program. > The error message points to line 8 in my program, which was your > line24. (Notice I used block delete to allow myself to view the > unoffset path.) > > http://timeguy.com/cradek-files/emc/viesturs-error.png > > Also notice that if line 8 had gone in another direction (say upward), > line 7 could have been reached just fine. This is why line 7 isn't > the error; it is the whole situation which causes the error and the > situation is finalized when line 8 is reached. > > The harder question you ask is what you can do to correct it. I don't > know the answer to that except to say that you must generate gcode > that does not have these unreachable moves if you need to use cutter > compensation. >
Ok, thank You for the explanation, I kind of realised that it is the case that there is corner that cannot be completely reached, because tool is too big. The way I see the ideal solution - display the error message so that I am warned about the situation, and continue with the code. Using Your screenshot - the displayed tool position would be the point, where tool should do the corner - stop and start moving downwards. That is the desired behavior in current situation. If I will have my CAM programm including the kerf size compensation in the code, it would produce this exact behavior - reach the corner as far as it can bu not moving over the next line (that would be the next line downwards in the screenshot) and then moving on... But I would like not to include compensation in the code so that I can manually tweak it, if I need it and that is why I like the G41/G42 commands as they do all the job. Is there a way to tell EMC that such a concaved corners are acceptable and EMC should move on? I think that plasma and laser tables also might be affected by this situation. > I did not check your first program with the arc problem because you > did not give enough surrounding lines for me to be sure that I would > see the same problem. As you can see above, the directions of > surrounding moves are relevant when the path is compensated. If you > do a similar examination I think you will be able to see the problem. > If not, post a screenshot or a complete (but minimal) program showing > the problem and I will try to help. Here is the whole G01/G02/G03 block with all the intro and outro lines. The trickiest part is that error is created in place, where tool has to move on the outer side of the turn (it has to do G02 move, when G41 is active). Another trick is that the part is symmetrical, but EMC does not like only one side, the other one is ok. G64 P 0.05 G90 M6 T1 F300 G0 X+75.917 Y+107.778 G41 M3 S100 M8 G4 P1.5 G3 X+76.064 Y+110.967 I+0.074 J+1.594 G3 X+40.813 Y+96.146 I-2.052 J-44.453 G2 X+38.415 Y+96.146 I-1.199 J+1.920 G1 X+33.000 Y+99.029 G3 X+26.819 Y+97.579 I-2.209 J-4.486 G3 X+27.052 Y+35.097 I+47.193 J-31.065 G3 X+28.022 Y+34.583 I+1.074 J+0.853 G1 X+39.928 Y+34.583 G2 X+45.159 Y+32.636 I+0.000 J-8.000 G3 X+59.223 Y+24.543 I+28.844 J+33.863 G2 X+60.512 Y+22.807 I-0.713 J-1.877 <--- my EMC version does not like this line. If I delete it, code is accepted G1 X+60.512 Y+17.516 G1 X+62.013 Y+16.014 G1 X+85.989 Y+16.014 G1 X+87.512 Y+17.516 G1 X+87.512 Y+22.807 G2 X+88.802 Y+24.543 I+2.003 J-0.140 G3 X+102.865 Y+32.636 I-14.789 J+41.970 G2 X+108.096 Y+34.583 I+5.231 J-6.053 G1 X+120.002 Y+34.583 G3 X+120.972 Y+35.097 I-0.104 J+1.367 G3 X+121.206 Y+97.579 I-46.960 J+31.417 G3 X+115.024 Y+99.029 I-3.973 J-3.036 G1 X+109.609 Y+96.146 G2 X+107.211 Y+96.146 I-1.199 J+1.920 G3 X+76.064 Y+110.967 I-33.199 J-29.632 G3 X+75.019 Y+110.640 I-0.074 J-1.598 M5 M9 G40 M2 ------------------------------------------------------------------------------ This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
