At 02:00 AM 7/30/2007, you wrote: > I'm getting going with emc2, after not having done nc/cnc work for a >long time (like, almost 30 years ago, before software took me away from >machining as a career). I've been messing with the G41/G42 tool comp >stuff, and have the lead-in moves working correctly. However, I've got >a question... > > I have run into the problem I see mentioned every now and then in the >archives, wherein the tool comp algorithm has problems with series of G1 >moves that were generated by some higher-level application to represent >an arc. This makes sense, since emc2 can't maintain tangential contact >with the material path at the vertices on the tool path. > > I was surprised to run into this, as my expectation was that > these arcs >would have been represented by equivalent G2/G3 arc moves instead of a >series of G1 moves. So, I started digging into the code behind every >open-source package I can find, including OOdraw, inkscape, qCad, >pstoedit, hp2xx, dxf2gcode, codeg, and probably some others I'm not >remembering right now. I have also reviewed every vector-based file >format ever invented. I consistently run into the same problem as I try >to build a software tool chain: somewhere between the cad/drawing >package and the g-code generator, one of the apps is converting arcs or >splines to series of lines. > > In my most recent attempts, the source drawing (OOdraw or inkscape, >exported to pdf, svg or dxf), has every corner radiused more than enough >to allow for the tool to make the cut. Unfortunately, I can't get those >radiused corners all the way down to g-code as arcs. > > I am determined not to use windows, and also to avoid paying for >software if I can manage it. More as an experiment than anything else, >but I'm an old-school open-source guy and I just figured there would be >kickin' solutions for all this stuff in open-source space at this point. > > What am I missing? How can I get a high-level 2d or 3d drawing > all the >way down to emc2 in g-code such that arcs are represented as G2/G3 moves >instead of series of G1 moves? > > Thanks! > >-Al
To get the G2/G3 moves you need to figure out where the arcs are getting converted to lines. My guess is right at the export from the CAD program to DXF, there is usually an option in the program as to how this is handled. What does the text in the DXF for a simple square look like? __________ Andre' B. Clear Lake, Wi. ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
