On Thu, Aug 19, 2010 at 09:31:42AM -0500, Viesturs L??cis wrote: > 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.
Yes I agree the ideal solution is to know what the *desired* behavior is and then do it - however there are two problems with that - knowing what the desired behavior is - and then doing it. I don't mean to be flippant, but both are very hard. Like Stuart S implied with his question, you don't actually program a part profile in gcode. EMC doesn't know anything about the shape of your desired part. It simply has a series of lines and arcs. It moves the tool along this path, or along the right or left of it. If you tell it to move the tool along the right side of a certain set of lines and arcs, but that task is impossible like in your example, it gives an error and stops. It does not try to guess what IS possible and maybe close enough to what you want... That way lies madness (and ruined work). It is better to give a clear error saying why the requested task is impossible, and then the gcode programmer can fix the problem. > 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. One thing you might consider is having the CAM compensate the path for your nominal tool diameter but leave in the G41/G42. Then run with a tool diameter of zero in your tool table, or if you want tweak the path, run with a very small positive or negative tool diameter that's the difference between your CAM's idea of the nominal tool and the actual tool. This makes G41/G42 move the path only a tiny amount as if there was a tiny tool. Offsetting a tiny amount makes it much less likely that you will have unreachable moves. > 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. Nope, for the reasons above. Chris ------------------------------------------------------------------------------ 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
