[Vern Smith]

I use CAM programming rather than take the time to learn G code which I realize is the lazy way out but it got me up and running much faster than I could have otherwise. I tried to make a modification to my CAM programs out put but the machine threw an out of machine limits message which does not seem to apply in this situation. I'm parting off a 3.25" diameter aluminum part with a .04 thick flange on one end so it can not be allowed to rattle around inside the housing.

I set up two parting operations, the first goes 99% of the way. The second parting op.,listed below, cutes the final thin section at slow rpm so I can be there to put a pencil in the hole and catch the part. This works fine except I cringe when the cutoff blade roars into the existing slot at warp speed. I do it now with single block and the rapids at 5% but that is cumbersome. I tried to get this move to happen at a more dignified pace by replacing line N250 with N250 G01 X0.56 F0.1 I'm sure you fellows will see the problem right off. Thanks for the help.

Vern

N170 T0303
N180 G54
N190 G99 G97 F0.002 S500
N200 M03
N210 /
N220 G18
N230 G00 Z0. X3.6
N240 Z-0.22
N250 X0.56
N260 G01 X0.4 F0.002
N270 G00 X0.56
N280 X3.6
N290 Z0.
N300 (END TOOL)
N310 M01
N320 M09
N330 G28 U0.
N340 G28 W0.
N350 M05
N360 M30

[Geof]

..... This works fine except I cringe when the cutoff blade roars into the existing slot at warp speed. .....

Why are you retracting the parting tool in the first place?

Part down to X.56 at whatever speed and feed you are using then just put M03 S500 and follow it with the X.4 F.002. The machine will simply pause at X.56 while the spindle slows down.

You could even do it with a M00 program stop like this:

(Part to X.56)
M00 (Stop spindle and give you time to find the pencil you just dropped)
M03 S500 (Hold pencil in right hand push green button with left; or vice versa)
G01 X.4 F.002 (Catch the part)
M05 (Stop the spinning thing for safety before lifting the part away)
X3.6
etc.

Mind you, I would feel much more comfortable if you rigged up something from the tailstock instead of the pencil. You might find life on CNCzone tedious typing with only one hand.

[Vern Smith]

The only way I can get the CAM software to stop everything so I can pick up and insert the pencil is to separate it into two distinct operations. I like your idea and would have preferred to do it that way but now we are back to my short circuiting the leaning process in the first place.

I understand the safety issue and can surely slow the RPM to say 200 which should keep the part from going anywhere except straight down. I'll plug your code (including the descriptions ) into the program this afternoon. It looks like the M00 not only stops the spindle but also any other axis movements?

[Geof]

M00 stops everything. It should be followed by M03 to restart the spindle however, I just thought about an additional line to my suggested code.


(Part to X.56)
G01 X.57 (Retract slightly so the tool is not touching when the spindle stops and starts)
M00 (Stop spindle and give you time to find the pencil you just dropped)
M03 S500 (Hold pencil in right hand push green button with left; or vice versa)
G01 X.4 F.002 (Catch the part)
M05 (Stop the spinning thing for safety before lifting the part away)
X3.6
etc.