RE: G02 Tolerance ?

["Tim Goldstein" <timg-at-ktmarketing.com>]

EMC is known for requiring G02/03 to be accurate to the nanometer or better.
I know there is a setting that then has to be compiled in, but don't
remember if it affects this or just the gouging on offsets?? I have gotten
past the radius problem by setting Vector to output using R and going to 6
decimal places.

Tim
[Denver, CO]

> -----Original Message-----
>
>
> In the last few days I've gotten a foreign knee mill running
> under CNC, at
> least X & Y.  It's using ball screws, 750 oz-in steppers with 2:1 timing
> belts, Camtronic 5A drivers, opto-isolation from a computer
> running Red Hat
> 6.2, rtlinux & EMC.  Now that it is functioning I'll have a bushel of
> questions, I hope you guys have some patience.  Thanks. :-)
>
> First, I have a question regarding the g-code G02 command.  The
> first thing
> I'm doing is machining belt guards for the timing belts.  In checking my
> code I get the error that the radius from the start point is
> different than
> the radius to the end point.  I thought this was my hand coding and
> rounding to .001 but I just created code using Yeager ACE and
> can't see any
> problem in the code.  The code that give the error is:
>
> G01 X0.047366 Y2.186987 f40
> G01 Z0.000000
> G01 X0.102140 Y2.880401 Z0.000000
> G01 X10.662027 Y2.046252 Z0.000000
> G01 X10.607085 Y1.350706 Z0.000000
> G02 X10.607085 Y-1.350706 I10.375000 J0.000000
>
> I think the only relevant commands are the last two.  Why does
> this create
> an error?  Is there a tolerance setting in EMC for this?  I could not see
> one in the '*.ini' file.
>
> The error occurred while running "sim.run" in what I think is the
> standard
> distrubution.  (Thus explaining the feed rate of 40, visual output via
> backplot no cutting.)
>
> I can work around this using radius R rather than center I&J but
> would like
> to know how to adjust this tolerance.
>
> Thank you.
>
> Hugh
>
> --------------------------------
>   Hugh & Denise Currin
>     currin-at-cdsnet.net
>     Klamath Falls, Oregon  USA
>     541/884-3023
> --------------------------------