Need Help!- Tool nose comp

[jorgehrr]

Hello there.
I need help adding G2 to a small program.
I'm making a circle 1.250 diameter with a tool .625 diameter
the program I have is:
from the center of the circle:

G2G91X.250Y0.R.125
G2I-.250
G2X-.250Y0.R.125 (WORKS GOOD not using tool compensation)

Now...I need to be able to adjust the 1.125 diameter, I'm trying this.

G2G91G42X.5625Y0.0R.281
G2I-.5625
G2X-.5625Y0.0R.281
G1G40Z1.0

But is not working (alarms out). Please where is the bug or advice for a different way to do this.

Thank you in advance.

George

[sinha_nsit]

G2G91G42X.5625Y0.0R.281

You cannot have G02 as the start-up move in radius compensation. It has to be G00 or G01. Thereafter you can switch over to G02/03.

[beege]

Originally Posted by jorgehrr Hello there. I need help adding G2 to a small program. I'm making a circle 1.250 diameter with a tool .625 diameter the program I have is: from the center of the circle: G2G91X.250Y0.R.125 G2I-.250 G2X-.250Y0.R.125 (WORKS GOOD not using tool compensation) Now...I need to be able to adjust the 1.125 diameter, I'm trying this. G2G91G42X.5625Y0.0R.281 G2I-.5625 G2X-.5625Y0.0R.281 G1G40Z1.0 But is not working (alarms out). Please where is the bug or advice for a different way to do this. Thank you in advance. George

Of course this depends on what control you are programming, but most don't like comps starting on arcs. Try a straight line move before the first arc, turning on your comp there, and turn off your comp in a line move after bringing the Z up.

[jorgehrr]

Thank you guys.
You have a point there, I completely forgot about that rule.
I'll turn it on in my rapid to the center of the hole (Z-.250).

Again...Thank you

George

[sinha_nsit]

X/Y move is needed. A Z move cannot incorporate radius compensation.

[laszlozoltan]

just open the nc file and edit out the g28 x0 y0 at the end or throw in your m30 before that line.

[jorgehrr]

So...If I want to keep the program the way it is starting and finishing with an arc move. ( finish is great) how and where do I turn compensation on.
Can you give some samples.
Regards.

[dcoupar]

Originally Posted by jorgehrr So...If I want to keep the program the way it is starting and finishing with an arc move. ( finish is great) how and where do I turn compensation on. Can you give some samples. Regards.

I don't believe you've told us what control it is. As beege said, it does matter. On a Fanuc, Yasnac, or Haas, you'll get a CRC interference alarm if you program a 0.218 inside radius with 0.3125 in the offset register (the way you have it now).

If you're dead-set on starting and finishing on an arc, use your "good" program and only put the amount you need to adjust into the offset register, and turn on the comp with the XY rapid to the center.

G0G42X0Y0
Z-0.25
G2G91X.250Y0.R.125
G2I-.250
G2X-.250Y0.R.125
G0G40G90Z1.0

Otherwise, add lead-in/lead-out lines to turn the comp on and off (per the attached .jpg).

Of course, that's assuming it's a Fanuc or similar control...

[jorgehrr]

I'm sorry. FANUC.
I have to try your sample. What I did for now is increase the value of X and I to make the circle a bit bigger.
Monday I'll change it to see if it works.
Thank you all for your help.
Regards

George