I have a cheap Chinese router which has rack and pinion drive to x and y and ball screw for the z axis. The control system is Nc Studio. Results are far from acceptable and accuracy is very poor. I know there could be mechanical issues causing loss of steps etc but I'm just trying to get my head around the whole thing.
Both x and y axes are driven by stepper motors configured to 2000 steps per rev and 1:5 reduction drive. Now the odd bit, the setting in NC Studio for these axes is 0.01042mm per step. So as I see it 10000 steps will move the axis through 104.2mm. Which is does! The pinion has 20 teeth so the rack pitch must be 104.2/20=5.21mm With me so far. This however does not correlate to the actual rack pitch which I measured as 3.955mm (measured over 100 teeth divided by 100) Why the difference and why on earth don't they simply use a rack with say 5mm pitch then the steps per mm setting would be simple to calculate. Using ball screws all the calculations would be simple. Am I missing something here?
Any help appreciated,
Bob.
Both x and y axes are driven by stepper motors configured to 2000 steps per rev and 1:5 reduction drive. Now the odd bit, the setting in NC Studio for these axes is 0.01042mm per step. So as I see it 10000 steps will move the axis through 104.2mm. Which is does! The pinion has 20 teeth so the rack pitch must be 104.2/20=5.21mm With me so far. This however does not correlate to the actual rack pitch which I measured as 3.955mm (measured over 100 teeth divided by 100) Why the difference and why on earth don't they simply use a rack with say 5mm pitch then the steps per mm setting would be simple to calculate. Using ball screws all the calculations would be simple. Am I missing something here?
Any help appreciated,
Bob.