well for what it is worth. i have used radius values for the last 2 years on my mill and it has been pretty good.
my mill is a full on VMC, its taiwinese thing chevalier 2040 similar to a haas VF3 and sat most of its life with a dead control so the bed ways are like new. (also have the linear rail version of the same machine) anyway i do quite a few injection molds on it and so far have never had a problem. i normally post the 3d surfacing code out at 0.02 mm step overs for the smaller details stuff and never had a problem with accuracy so i think for most people it doesn't matter. cheers andrew On Mon, Feb 7, 2022 at 5:56 PM dave engvall <dengv...@charter.net> wrote: > Hi, > I've read the assertion many times that ijk is better than radius and > always assumed it to be correct; but by how much. > Few of us run machines and are 'new' tigjht ;-) Maybe I've not looked > in the right place(s) > for an analysis or for demonstrated interp of circles with some kind of > error band. Any proof and or experimental evidence? > Just poking the bear. ;-). > > Dave > > On 2/7/22 1:01 PM, andrew beck wrote: > > One option is set your post processor to post radius not ikj values. > > > > > > That helped me once. > > > > They are much more forgiving > > > > On Tue, 8 Feb 2022, 09:48 Stuart Stevenson, <stus...@gmail.com> wrote: > > > >> Something is fishy between the Y values. > >> You have Y4.xxxx in the first list and Y0.xxxx in the full listing. > >> > >> On Mon, Feb 7, 2022 at 2:39 PM Stuart Stevenson <stus...@gmail.com> > wrote: > >> > >>> I see it in your gcode file listing > >>> > >>> On Mon, Feb 7, 2022 at 2:39 PM Stuart Stevenson <stus...@gmail.com> > >> wrote: > >>>> Where is the decimal point in the X value of "End=(X14444, Y0.8964)"? > >>>> I would say it is X1.4444 and expect this is a typo when you entered > >> this > >>>> in the email. > >>>> > >>>> > >>>> On Sun, Feb 6, 2022 at 11:12 PM Andy Howell <a...@gamubaru.com> > wrote: > >>>> > >>>>> We had been cutting with the same gcode when suddenly it came up with > >> an > >>>>> error: > >>>>> > >>>>> Radius to end of are differs from radius to start: > >>>>> > >>>>> Start=(X1.4208,Y4.8728) > >>>>> > >>>>> Center=(X1.4208, Y4.8964) > >>>>> > >>>>> End=(X14444, Y0.8964) > >>>>> > >>>>> r1=0.0236 > >>>>> > >>>>> r2=4.0001 > >>>>> > >>>>> Its got to some config issue. The same file runs in the simulator > just > >>>>> fine. That r2=4 is curious. We are cutting in a jig using fixture > G55. > >>>>> We had touched off the Y by 4 inches to run the file again. That > worked > >>>>> fine. We more the Y back 4 inches and touched off again to set the > G55 > >>>>> back to its actual 0,0 origin. When we ran the time, we started > getting > >>>>> this error. > >>>>> > >>>>> This is the code in question. Its complaining about line N70. > >>>>> > >>>>> % > >>>>> (TEST PIECE 4IN) > >>>>> (MY PROGRAM COMMENT) > >>>>> (T1 D=0.2362 CR=0. - ZMIN=-0.11 - FLAT END MILL) > >>>>> N10 G90 G94 G17 G91.1 > >>>>> N15 G20 > >>>>> N20 G53 G0 Z0. > >>>>> (BORE6) > >>>>> N25 T1 M6 > >>>>> N30 S18000 M3 > >>>>> N35 G55 > >>>>> N40 G0 X1.3853 Y0.8728 > >>>>> N45 G43 Z0.6 H1 > >>>>> N50 G0 Z0.08 > >>>>> N55 G1 Z0.0236 F20. > >>>>> N60 G18 G2 X1.409 Z0. I0.0236 K0. > >>>>> N65 G1 X1.4208 > >>>>> N70 G17 G3 X1.4444 Y0.8964 I0. J0.0236 > >>>>> > >>>>> Any ideas about what is wrong? We are running LinuxCNC 2.7.15. > >>>>> > >>>>> Thanks. > >>>>> > >>>>> > >>>>> > >>>>> _______________________________________________ > >>>>> Emc-users mailing list > >>>>> Emc-users@lists.sourceforge.net > >>>>> https://lists.sourceforge.net/lists/listinfo/emc-users > >>>>> > >>>> > >>>> -- > >>>> Addressee is the intended audience. > >>>> If you are not the addressee then my consent is not given for you to > >> read > >>>> this email furthermore it is my wish you would close this without > >> saving or > >>>> reading, and cease and desist from saving or opening my private > >>>> correspondence. > >>>> Thank you for honoring my wish. > >>>> > >>>> > >>> -- > >>> Addressee is the intended audience. > >>> If you are not the addressee then my consent is not given for you to > read > >>> this email furthermore it is my wish you would close this without > saving > >> or > >>> reading, and cease and desist from saving or opening my private > >>> correspondence. > >>> Thank you for honoring my wish. > >>> > >>> > >> -- > >> Addressee is the intended audience. > >> If you are not the addressee then my consent is not given for you to > read > >> this email furthermore it is my wish you would close this without > saving or > >> reading, and cease and desist from saving or opening my private > >> correspondence. > >> Thank you for honoring my wish. > >> > >> _______________________________________________ > >> Emc-users mailing list > >> Emc-users@lists.sourceforge.net > >> https://lists.sourceforge.net/lists/listinfo/emc-users > >> > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
