Problem with G02/G03 on Fanuc 21tb

[dj_deadman666]

I'm working on a program for school (I am a senior in Precision Machining 2) and for some reason in this program is mixes up G02 and G03. When I program a clockwise radius with G02 is makes it counter clockwise, when I program a counter clockwise radius with G03 it makes it clockwise. I've spent the past two days trying to figure out what’s wrong with it. G02/G03 has always worked fine in all my other programs but for some reason they decided to mix up in this program. Is it possible that for some reason the program corrupted itself (happened with our Centurion 7 Milltronics conversational mill, took me almost two weeks to figure it out and ended up having to dump all the programs and reload all the parameters) and just doesn't want to work? In that case should I just delete the program completely and re-enter it under a new program name? I'm completely lost; I'm at the point of just completely scrapping the program and starting from scratch.

And I figure it might be helpful if I mention I'm running it on a Emco Concept 55 turn.

Any help or suggestions are greatly appreciated.

Thanks,
Max

[christinandavid]

Is this your first turning program? Can you program something simpler and see if the same thing occurs?

Don't know much about turning concepts, but on a mill it is possible to look at the job from operators point of view, rather than the machines point of view, when using a different working spindle axis ie G17/18/19...if you program the contour looking from the wrong direction you would get that effect!

DP

[underthetire]

Is it a slant bed lathe? Is your tool in the correct (upside down) position? Is mirror image turned on? Is it a -x machine or +x machine? Lots of variables here.

[dj_deadman666]

Originally Posted by christinandavid Is this your first turning program? Can you program something simpler and see if the same thing occurs? Don't know much about turning concepts, but on a mill it is possible to look at the job from operators point of view, rather than the machines point of view, when using a different working spindle axis ie G17/18/19...if you program the contour looking from the wrong direction you would get that effect! DP

I've wrote quite a few programs, (not to boast but next week I'm competeing in CNC TURN at SkillsUSA Ohio competition, already took gold at local and reigonal) and the G02/G03 has always worked before. I checked and rechecked the program, I found a few errors and fixed them but made no difference on the problem. If needed I could post the program and print to give a better view of what going on.

The only view the graph function allows just shows the contor of the part through the tool path.

[underthetire]

Check your settings page, make sure something like mirror image is not on. Never seen a fanuc just start doing things backwards. Something had to have been turned on by accident.

[dj_deadman666]

Originally Posted by underthetire Is it a slant bed lathe? Is your tool in the correct (upside down) position? Is mirror image turned on? Is it a -x machine or +x machine? Lots of variables here.

It is a slant bed lathe. Its in the correct position. I've never used mirror image in any of my other programs and it works fine (frankly I'm not quite sure how to).

[dj_deadman666]

Originally Posted by underthetire Check your settings page, make sure something like mirror image is not on. Never seen a fanuc just start doing things backwards. Something had to have been turned on by accident.

Ok, i'll make sure to check tomorrow. Thanks so much.

Though i'm not sure if anything would have been turned on and what not because I transfered the program from the one lathe to the other(the school owns two concept turn 55's) and it did the same thing.

[underthetire]

If two machines are doing the same thing, you need to post up your program here. Error somewhere in the program.

[sinha_nsit]

The same thing happens on one of our trainer lathes with a non-standard control. But the reason is logical. It is not a rear-type lathe. The tool is on the front side, and the X-axis points toward the operator. This makes Y-axis point downward (using right-hand rule). CW/CCW is defined, looking in the negative Y-direction. Naturally, G02 becomes CCW, and G03 CW, from the operator's side.