G18, G02, cncsimulator

Lloyd wrote: "What can their simulation software do that
www.cncsimulator.com cannot?"


Hi,

I have a question regarding G18 and G19 (selectiion of XZ and YZ
planes). Is it possible that one can do an arc in the XZ plane
without bothering to specify G18?

I found a sample program (machining a positive mould of a bottle)
(G17 XY plane initialized)

N20 G00 Z20
N30 G00 Y120
N40 G00 X-9.449 Y120.5 T4 (dia 4mm)
N50 G01 Z-20 F200 S150
N60 G02 X9.449 Z-20 I9.449 K0
N70 G01 X9.5 Y120
N80 G01 Y118.5
N90 G03 X-9.5 I-9.5 K0
N100 G01 Y116.5
N110 G02 X9.5 Z-20 I9.5 K0
.......
...

In sequence N50, the tool is at X-9.449, Z-20
N60 will send the tool in an arc in the XZ plane to endpoint X+9.449
Z-20 just by specifying I and K? This is without any invokation of
G18?

Also, I have a question regarding the polarity (CW, CCW), refering to
the diagram below:

+Z
|
|
|
|
|
|
|
|
|_______________________\ +X
-9.449 0 +9.449

+Y is INTO the screen, -Y is OUT of the screen towards reader.
N60 G02 X9.449 Z-20 I9.449 K0 should send the tool in a clockwise arc
from -9.449 to +9.449, center 0, should the CW not be as seen from
+Y, which means that it will be downward and to the right from X-
9.449 (CCW as seen by reader from -Y direction)? However, in the
simulation, the tool was shown as going up and to the right, which as
seen from +Y will be CCW?

The program CNCsimulator, including the part program (in mill folder)
under consideration, can be downloaded from
www.cncsimulator.com

Peter