Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: fastflyer on July 28, 2012, 08:46:07 PM

Title: arc programming question
Post by: fastflyer on July 28, 2012, 08:46:07 PM
Hello,

I seem to be having an issue with mach3 and I am convinced it is a software config issue. My Mach3 does not like running arcs using I and J (inc. programming), it will not draw a proper arc in the display and when running on the mill it will feed around a lot quicker than programmed. I am sure it is programmed correctly because I tried other variations and Mach3 did not accept them at all. The way it does work is if I just replace the I and J with the "R" command, it then does a proper arc at the programmed feed rate. This convinces me it is software (or incorrect programming) not a machine issue. Does anyone have any ideas?
The incremental arc option is checked in general config.

If you copy and paste the prog into mach3 you can see what i mean about the incorrect arc,
it is not starting or ending tangentially.....
 
Here is the program that is not working:-

G00 G17 G20 G40 G49 G80 G90

T4 M06 (3/16 slotdrill)
G00 G54 X0. Y.2 M03
G00 G43 H4 Z2.0
Z.1
G01 Z0. F5
z-.02
y0. F15.
X1.165 Y0.
G02 X1.44 Y-.275 I-.275 J0.
G01 Y-1.22
G00 Z.25
X0 Y.2
G01 Z0. F5
z-.02
y0. F15.
X-1.165
G03 X-1.44 Y-.275 I.275 J0.
G01 Y-1.22
G00 Z.25
X0 Y.2
G01 Z0. F5
z-.039
y0. F15.
X1.165
G02 X1.44 Y-.275 I-.275 J0.
G01 Y-1.22
G00 Z.25
X0 Y.2
G01 Z0. F5
z-.039
y0. F15.
X-1.165
G03 X-1.44 Y-.275 I.275 J0.
G01 Y-1.22
G00 Z.25
X0 Y.2
G90 G00 Z2.00
M05
M30

Here is the program that is working:-

G00 G17 G20 G40 G49 G80 G90

T4 M06 (3/16 slotdrill)
G00 G54 X0. Y.2 M03
G00 G43 H4 Z2.0
Z.1
G01 Z0. F5
z-.02
y0. F15.
X1.165 Y0.
G02 X1.44 Y-.275 R.275
G01 Y-1.22
G00 Z.25
X0 Y.2
G01 Z0. F5
z-.02
y0. F15.
X-1.165
G03 X-1.44 Y-.275 R.275
G01 Y-1.22
G00 Z.25
X0 Y.2
G01 Z0. F5
z-.039
y0. F15.
X1.165
G02 X1.44 Y-.275 R.275
G01 Y-1.22
G00 Z.25
X0 Y.2
G01 Z0. F5
z-.039
y0. F15.
X-1.165
G03 X-1.44 Y-.275 R.275
G01 Y-1.22
G00 Z.25
X0 Y.2
G90 G00 Z2.00
M05
M30

Thanks,

Richard.
Title: Re: arc programming question
Post by: cncalex on July 28, 2012, 10:06:56 PM
Hi Richard,
your I and J values are reversed. This should work:

G00 G17 G20 G40 G49 G80 G90

T4 M06 (3/16 slotdrill)
G00 G54 X0. Y.2 M03
G00 G43 H4 Z2.0
Z.1
G01 Z0. F5
z-.02
y0. F15.
X1.165 Y0.
G02 X1.44 Y-.275 I0. J-.275
G01 Y-1.22
G00 Z.25
X0 Y.2
G01 Z0. F5
z-.02
y0. F15.
X-1.165
G03 X-1.44 Y-.275 I0. J-.275
G01 Y-1.22
G00 Z.25
X0 Y.2
G01 Z0. F5
z-.039
y0. F15.
X1.165
G02 X1.44 Y-.275 I0. J-.275
G01 Y-1.22
G00 Z.25
X0 Y.2
G01 Z0. F5
z-.039
y0. F15.
X-1.165
G03 X-1.44 Y-.275 I.0 J-.275
G01 Y-1.22
G00 Z.25
X0 Y.2
G90 G00 Z2.00
M05
M30
%

Alex
Title: Re: arc programming question
Post by: fastflyer on July 28, 2012, 10:52:50 PM
Doh! Thanks for that, can't tell you how long I stared at the program trying to figure it out. Jeez.

Richard