Need Help with G2

[eliko2000]

Hi,
very nice site.
So I have started reading the G-CODE manual and I found that I can stop the G2 movement at a specific X o(or Y) without calculating the Y (or X).
I have attached a ss of the relevant part of the manual.
you can see in the bottom that theoretically the movements stops at x=10,y=99.499
When I try this with my machie - It plots the error - because he thinks i am trying to get to (-10,70.711).

so bottom line - How can I stop G2 movement by stating only one coordinate?

[sinha_nsit]

Post your code which gives error.

In any G-code, if some coordinate value is not changing, then it need not be explicitly programmed. Machine would assume this.

[eliko2000]

Post your code which gives error.

In any G-code, if some coordinate value is not changing, then it need not be explicitly programmed. Machine would assume this.

Yes, I know this.
But if you check the bottom of the ss. The manual shows that you can stop at a different coordinate without stating it.

He choose x=10 and the arc stopped when the tool got to x=10..resulting in y=99.499.

How can I achieve that also?

p.s
I used the same code from the manual

[RCaffin]

Ah, but what program are you using to drive the CNC?
Not all programs do what they claim.
And you need to be a shade cautious with arcs, as the controller NEEDs certain info to work.

Cheers
Roger

[Fletch_CNC]

The manual shows that you can stop at a different coordinate without stating it.

Is it the manual for your machine, or a general G-code manual? That makes a big difference. Have you tried inputting the Y-coordinate on the line, just to make sure there isn't something else wrong with the code you've entered?

[RCaffin]

I found the instruction in the JPG rather confusing anyhow. They just didn't make sense.At least, some strange errors.
Chinese manual maybe?

Cheers
Roger

[eliko2000]

I found the instruction in the JPG rather confusing anyhow. They just didn't make sense.At least, some strange errors.
Chinese manual maybe?

Cheers
Roger

I have Okuma MULTUS MB46 and it uses OSP-P300M.
The ss is from the manual from the machine itself.

When I addd the Y coordinate it works.
I'm just trying to use this feature from the manual but it seems that I cant.
Any Ideas?

p.s
The manual is Japanese

[RCaffin]

I think the manual is just plain wrong. You will need to create your own test program, using either the R format or the IJK format.
You will also need to check whether you are in absolute or relative mode. Chuckle - this is where everyone has some problems!

Cheers
Roger

[eliko2000]

Thanks for replying so quickly.
I did wrote my own program with IJK while being in G90.
From your experience is there a possibility to stop the arc movement in a specific x or y?

[RCaffin]

There's usually no problem in the IJK format with specifying the destination with just X OR Y.
After all, you have the centre and the start points, so you can calculate the radius. Then you solve the quadratic for the two results you always get and pick the appropriate (nearest) one.

I don't think you can do that with the R format: not enough constraints.
EDIT: I was partly wrong. Oops! Sorry.
IF the controller can assume that the unspecified axis has not changed, then there are enough constraints to solve for the centre of the circle.
So if you are at -1,0 and you specify G2 going to X=+1 with R=1.5 AND the controller assumes an unchanged Y value, then it works.

Cheers
Roger

[sinha_nsit]

From your experience is there a possibility to stop the arc movement in a specific x or y?

I do not think so, though it may be control-dependent.
If you do not specify, say, X, then same X (that of the start point) is assumed. A different Y would be an impossible arc.