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After a lot of faffing I managed to get it pretty much all working, find the post processor (stepcraft one) one the Autodesk site etc, all axis moving and homing fine.

Tried a simple bolt pattern with bored holes as an air cut, but as soon as I hit cycle start it wants to send all the axis off to 0, Z goes up, sets off the limit switch then X/Y go off to 0/0 with the limit switch still light up as Z didn't come down off the end stops.

All the axis where homed, then moved to a central location and zeroed, on the screen X/Y where centre but are moving off to the bottom right heading for 0/0

Any pointers?

The highlighted line of code, G53 X0 Y0 is sending it there.
Delete that line of code.

Well, that is what your g-code has to do.
The first line of code on your printscreen is G0 G53 Z0 which means move to Z=0 in the machine coordinate system.
The next line is G53 X0 Y0 which means move to X=0 and Y=0 in machine coordinates.
Machine coordinates are in reference to the home position.
You can check your actual machine coordinates if you switch the machine coords toogle button on.

I don't know what do you mean by "sets off the limit switch"?
A movement can't set off a limit switch. If your limit switch is active then you can't produce movement except if you override the limits.
So, I don't really understand your description or what you want to achive or what the issue is?

Skipping the limit switches for the moment.
I'm missing something here, I understand the G code you guys pointed out is sending it to the zero point, what I'm not understanding is all the axis where zeroed before I started the program so surely they should not be moving anywhere?

Grrr, ok just dawned on me G53 is zero in the machine coords.


edit2, just went back and output the same CAM with the Mach3 post and it doesn't have anything of that at the start. Going to have to work out how to strip that out of the post or it's going to be a pain doing it manually every time.

The bit that is messing me up is :

(Move to tool change position)
G53 X0. Y0.

Is there any way to set the tool change position in UCCNC? as the preferred is to leave the X/Y where it is and just move up Z. I'm doing manual changes so going all the way out to the end stops isn't needed especially as my machine isn't very fast.

Also am I right in thinking this is the correct post processor to use as 36 downloads seems a little low.
http://cam.autodesk.com/posts/?p=uccnc

Thanks

The UCCNC will only do what you (your code) will tell it to do.
So, I think the question is not really about if the UCCNC can do a movement to a tool change position, because ofcourse it can do that if the g-code contains a code which sends the axes to a tool change position.

Usually a manual tool change is done though is not with the movement code for the tool change is in the g-code, but an M6 code is inserted by the CAM software and that macro contains the commands for the tool change procedure.
If the new tool is for example T1 then an M6 T1 is insterted into the proper place in the g-code program.
The UCCNC is set in setup to execute the M6 macro on tool change, so it will execute the code you place in the M6 text macro.
And in the M6 macro you can code any kind of movements, you can code an automatic toolchange procedure which is tool number dependent or you could code just a movement to a fixed place.
What you code in the M6 macro is only up to you, it depends on what you want the machine to do when the machine needs to do to change a tool.