G code is not working...

The error is pretty clear your radius is off for your arc by a whole bunch. This usually means you were not properly positioned at the start of the arc or your offsets are not correct. You can turn off the line numbers on your post processor as they are not needed.

When I'm writing a post processor for any control I start with a line then add an arc and get that to work in all directions and quadrants before trying a complex part. This rather simplifies the process. I also start with arcs of a known size and that makes it easy to see if the code generated it what I expected. I also use the Arc Buddy to generate my code to check my post against.

John

What error is it giving? I suspect that it is an arc-centre error?

You might find that a G91.1 helps, the G-code is using relative arc-centres and it is possible that your EMC is in absolute.
www.linuxcnc.org/docview/html//gcode_main.html#sec:G90.1,-G91.1

BigJohnT wrote:

The error is pretty clear your radius is off for your arc by a whole bunch.

I checked it in Excel and it seemed spot-on to me, but only in incremental mode.

axel88 wrote:

So far I found out how to:
-Change gcode "numbers"
-set Feed Rate, Linear Axis Travel Limits, Linear Motion Resolution, Home Position
-create/modify start and end sequences

Arc centre tolerance is 0.0002" or 0.002mm so you probably need to make sure that the preprocessor outputs positions to at least that accuracy.

axel88 wrote:

In my postprocessor is defined:G90 Absolute Mode
G91 Incremental Mode
and that's the same as in the documentation./quote]

That is for linear moves so sets a different thing.

For 90.1 and 91.1 i can't find any defenition in the Post Builder.

I think EMC2 is unusual in allowing you the choice of how to define IJK arcs. Your postprocessor clearly works in incremental arcs, so it might be enough just to add G91.1 to the header block.
The first experiment required would be to add it by hand at the beginning of that G-code and see if it helps.

Linear Motion Resolution is set as 0.0075mm so if i don't know how to influence the preprocessor could i raise this value?

You need to make it smaller. .001 would be better. Knowing nothing at all about Unigraphics I don't know if you can change it.

andypugh wrote:

BigJohnT wrote:

The error is pretty clear your radius is off for your arc by a whole bunch.

I checked it in Excel and it seemed spot-on to me, but only in incremental mode.

I just loaded the first few lines of code up in Axis and didn't check much beyond that...

John

BigJohnT wrote:

I just loaded the first few lines of code up in Axis and didn't check much beyond that...

Your test is probably better than mine, I just checked line 13.

Is there a way to copy the exact error message? (Is it duplicated in dmesg or stdio?)
It might be instructive to find out what the numbers are.

Does a G91.1 help? (I think G91.1 is default, if it is then it shouldn't)