Hey guys. Sort of a noob to CNC, not so much to machining.
Here's the deal. I've got my CNC machine all set up, and I'm using Mach 3. I can go anywhere in my 98"x50" table within 0.003." I am certain that my backlash is compensated properly, I am not missing any steps, and that my steps per are dead on. In short, if I enter the MDI screen and give a "g0" instruction, the machine goes exactly where I expect it to, and the on-screen DRO and real-life measurements reflect that.
My problem arises when I am running G-code. My on-screen DRO (incidentally where the real life tool is) gets out of sync with the G-code instructions.
You can see from the screenshot below that I am stepping the G-Code with the "Single BLK" command and that Mach3 just received the "G1 9.6894" command, but my router actually moved to +9.7064, which is 17 thousanths out! This is verified by real life measurement.
Here are the links to my G-Code.
Part I'm discussing
Other Part I'm having trouble with
I'm not sure what I'm supposed to do here, the errors seem to be random anywhere up to 0.035". I have tried enabling/disabling backlash compensation (and restarting program like it says), it only makes things worse due to wiggly backlash.
The crazy thing is, if I stop the G-code, click "goto z" and then goto the MDI page, it now includes that stupid offset. For example "G0 y0.2" goes to +0.217, no matter what I "G0" it adds .017 to it and sends that to the DRO and the machine.
Please help a confused man.
Thanks
-GB Ward