Positioning Accuracy Not Working as Desired

Hello,

I am using LinuxCNC on a grinder, I set the deadband of each Axis to .000015, the default value, but LinuxCNC will not always be that accurate. For example if I command an axis to go to 0, it goes to -.0008. LinuxCNC does not error out. I need the high level of accuracy for the parts the grinder needs to make.

My hal and ini files are attached.

Thanks