Igor, I don't have an answer for you, other than to check on how you've defined you trajectory planning accuracy outside of this routine.
Why are you using two half circles? You could just send the cutter back to the starting xy location in a single G2 instruction. N. Christopher Perry On Sep 25, 2012, at 14:20, Igor Chudov <[email protected]> wrote: > I have a routine that lets me mill a deep circle in several passes, > typically to cutout circles from plates. > > Something strange is going on and the resulting shape is not exactly round. > It can be best described as a circle with humps. > > The routine is below. It is basically a while loop, milling progressively > deeper until Z reaches the required depth. Every loop consists of two half > circles milled helically, with the end mill going down along a spiral. > > Any idea why the shape may not end up being circular? > > Thanks > > Routine attached. > > (Copyright - Igor Chudov, released under GNU Public License V3) > > O<circulargroove> sub (circular groove, good for milling through holes too) > #<xc> = #1 (X center) > #<yc> = #2 (Y center) > #<safez> = #3 (safe height) > #<depth> = #4 (depth of milling) > #<radius> = #5 (outside radius) > #<milld> = #6 (end mill diameter) > #<frate> = #7 (feed rate) > #<zstep> = #8 (z step, per circle, optional) > > O<if> if [ #<frate> NE 0 ] > F#<frate> > O<if> endif > > O<if> if [ #<zstep> EQ 0 ] > #<zstep> = [#<milld>/3] > O<if> endif > > #<z> = #<safez> > #<r> = [#<radius> - #<milld>/2] > > G0 Z#<safez> > G4 P0 > G0 X[#<xc> + #<r>] Y#<yc> > > O<loop> while [ 1 ] > > O<if> if [ #<z> - #<zstep> LT #<depth>] > #<zstep> = [#<z> - #<depth>] > O<if> endif > > G2 X[#<xc> - #<r>] Y#<yc> Z[#<z> - #<zstep>/2] R#<r> > G2 X[#<xc> + #<r>] Y#<yc> Z[#<z> - #<zstep>] R#<r> > > #<z> = [#<z> - #<zstep>] > > O<if> if [ #<z> LE #<depth> ] > O<loop> break > O<if> endif > > O<loop> endwhile > > G2 X[#<xc> - #<r>] Y#<yc> R#<r> > G2 X[#<xc> + #<r>] Y#<yc> R#<r> > > G0 Z#<safez> > > O<circulargroove> endsub > > M2 > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
