As the heading goes, sheetcam output is metric, mach 3 settings are also for metric, however mach 3 DRO shows in inches. The gcode is in metric but when I enter gcode direct into mach 3 it travels in inches. Entered G00 X10 and x axis moved 10 inches. I want this in metric, had this sort of problem many years ago and connot remember how it was resolved. Looked up in search, nothing, looked in the manual for mach3 also cannot find anything. Last time using machine all was OK today inches display. Need to get some parts cut and this is now annoying me, more so as cannot remember how to change it back to how it was. Also can’t remember what I did to get it to this in the first place 
In SheetCam go to Options->machine->post processor. Make sure it is set to metric.
Yes Les it is in metric. Even the Gcode in mach 3 when loaded up at the top says G21 (units metric). It is only Mach 3 which is operating in inches. I just don’t have a table that is 1188" by 2390". This would make the item quite large to handle. Any suggestions as to how to change thin in mach 3
Just for your info Les, I tried a old file, which is in metric and it seems that Mach 3 is multiplying everything by a factor of 25.4. My safety Z clearance is 57.5mm so mach 3 decided to go 57.5 inches, subsequently the z drive stalled out at the mechanical stops. I am stumped and don’t know what to do on resolving this, any further suggestions. Thanks in advance
In Mach go to Config->Set native units. If the units are set to mm, set them to inches. I think that could do it.
Good morning Les. No it didn’t and now it is worse. Nothing goes. I, in mach 3 reset setting from 22 program runs ago and now no smooth stepper. This is now killing me.
Good morning Les. Just thinking back all seemed to be running fine before changing to the suggested post processor. I didn’t run any movement of the plasma table just tried to see if the gcode would load up. Could that have any bearing. I am grasping at straws now.
problem resolved. Mach 3 unit of measure is inches, so native units must be set to inches, saved and all is good. I have created this problem trying t fix other issues and not quiet understanding what I am doing. 
We live and learn, hope I have learnt a lot 