Another odd bug like behavior I am seeing. Set up a tool in the tool table with an extremely small diameter, load that tool, and run the g-code below with the optional block skip on and then again with it off.
G64 G43 G0 X1.5 Y.375 Z1 /G41 G1X1Y.5Z.5 G1X0.5 G2 X4.5 I2 J0 G1 X0.75 G0Z1 G40 Notice how having G41 turned on seems to shut off blending. Why is that? ----- Original Message ----- From: "Todd Zuercher" <zuerc...@embarqmail.com> To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> Sent: Friday, February 17, 2017 11:25:06 AM Subject: Re: [Emc-users] G41-42 and G64 Bug?q The small radius "is" the tool radius, and it was created by Linuxcnc when it created the G41 tool offset. ----- Original Message ----- From: "Jim Craig" <jimcraig5...@windstream.net> To: emc-users@lists.sourceforge.net Sent: Friday, February 17, 2017 9:27:23 AM Subject: Re: [Emc-users] G41-42 and G64 Bug?q Todd, Is the cutter radius larger than the small radius transitioning from the straight line to the semicircle. would this cause the issue? Grasping at straws here as I don't use G41/G42. I guess I don't understand why the small arc radius is being shown at all in white if the below code is the programmed path. Jim On 2/16/2017 3:04 PM, Todd Zuercher wrote: > Maybe, it is or isn't a problem. > The g-code is only: > > G43 > G0 X1.5 Y.375 Z1 > G41 > G1X1Y.5Z.5 > G1X0.5 > G2 X4.5 I2 J0 > G1 X0.75 > G0Z1 > G40 > > It runs perfectly fine without the G41 reguardless of the G64 setting. I > guess the planner must see that arc in the transition from one line to the > next in G41 and the Q is acting it, even though it isn't actually written in > the g-code. > Something else to remember when using tool comp. > > > ----- Original Message ----- > From: "sam sokolik" <sa...@empirescreen.com> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Sent: Thursday, February 16, 2017 3:20:02 PM > Subject: Re: [Emc-users] G41-42 and G64 Bug? > > On this post - I showed what happens to a shape as you increase Q > > http://www.cnczone.com/forums/linuxcnc-formerly-emc2-/206712-software.html#post1453562 > > sam > > On 2/16/2017 2:11 PM, Kurt Jacobson wrote: >> OK, I see that you mean now. As they say, a picture is worth a thousand >> words. (Though that does not seem to hold true when writing an essay for >> English class!?) >> >> I still think naive cam detector is doing exactly what it is suposed to. If >> the maximum deviation of an arc from a strait line is within Q they are >> collapsed into a single linear move, which is exactly what I see in your >> screen dump. >> >> Kurt >> >> On Thu, Feb 16, 2017 at 2:53 PM, Todd Zuercher <zuerc...@embarqmail.com> >> wrote: >> >>> I didn't expect the Naive cam detection to do this. >>> https://s2.postimg.org/ezy3wjfjt/bug.png >>> Maybe I am reading the docs wrong. >>> >>> ----- Original Message ----- >>> From: "Kurt Jacobson" <kurtjacob...@bellsouth.net> >>> To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> >>> Sent: Thursday, February 16, 2017 2:10:26 PM >>> Subject: Re: [Emc-users] G41-42 and G64 Bug? >>> >>> I don't really know any thing about this, but I'd say that is the expected >>> behavior based on the description of G64 Path Blending: >>> >>> "On G2/G3 moves in the G17 (XY) plane when the maximum deviation of an arc >>> from a straight line is less than the G64 P- tolerance the arc is broken >>> into two lines (from start of arc to midpoint, and from midpoint to end). >>> those lines are then subject to the naive cam algorithm for lines.[1]" >>> >>> It sounds like your Q value is larger than the radius of your compensation >>> lead out, so the arc is broken up into two line segments. Since these line >>> segments are within Q of a linear move they are collapsed into one linear >>> move, and since this linear move is within Q of the original linear move >>> the whole path is collapsed in to a single linear move which is treated >>> essentially becomes a long compensation lead out move. >>> >>> Just thinking out loud here, again, I am a complete noob so take this with >>> half a grain of salt. >>> >>> [1] http://linuxcnc.org/docs/html/gcode/g-code.html#gcode:g61-g61.1 >>> >>> Kurt >>> >>> On Thu, Feb 16, 2017 at 1:32 PM, Todd Zuercher <zuerc...@embarqmail.com> >>> wrote: >>> >>>> I was playing arround with G41 and G42 in a simulation and I think I >>> might >>>> have found a bug with the Naive CAM Detection. >>>> The shape I was simulating was a semi circle with the start/end point on >>>> the flat side and a single G2 arc move connecting the end points. >>>> The simulation behaves strangely. With a tool radius of .125" and .25" >>> and >>>> staight G64 the tool path precisely followed the path (white and red >>> lines >>>> over lapped). With G64P0.001, the same. The expected behavior is cutting >>> a >>>> straight line parallel to the programed line offset the tool radius, cut >>> an >>>> arc around that end point to connect to the offset path of the commanded >>>> arc cut. all good right. >>>> With G64P0.001Q0.2 there is odd behavior. It moves in a straight line >>> from >>>> the beginning of the compensated straight line cut to the begining of the >>>> compensated arc cut completely ignoring the compensated end point of the >>>> straight cut. I know having such a large Q setting is a little odd. I >>> also >>>> see simular behavior with G64P0.2 (no Q specified, same as Q0.2) only >>> with >>>> more rounded corners. >>>> I seem to see the odd behavior when ever Q is about 2/3 or more than the >>>> tool diameter. >>>> >>>> -- >>>> >>>> ======================================== >>>> >>>> Todd Zuercher >>>> mailto:zuerc...@embarqmail.com >>>> >>>> ======================================== >>>> ------------------------------------------------------------ >>>> ------------------ >>>> Check out the vibrant tech community on one of the world's most >>>> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >>>> _______________________________________________ >>>> Emc-users mailing list >>>> Emc-users@lists.sourceforge.net >>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>> >>> ------------------------------------------------------------ >>> ------------------ >>> Check out the vibrant tech community on one of the world's most >>> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >>> _______________________________________________ >>> Emc-users mailing list >>> Emc-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >>> ------------------------------------------------------------ >>> ------------------ >>> Check out the vibrant tech community on one of the world's most >>> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >>> _______________________________________________ >>> Emc-users mailing list >>> Emc-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >> ------------------------------------------------------------------------------ >> Check out the vibrant tech community on one of the world's most >> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> >> > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
