I am having some unforeseen problems with my machine.
I tried to cut a 1" circle using the different microstepping possibilities of my stepper motors.
The motors are 1.8° nema23 steppers. The biggest problem is that 1 full step on my stepper is 0.5mm of travel.
So I tried 25x microstepping and thought that I might get 0.02mm step resolution.
The result is something completely different. Instead of 0.02mm step resolution I get the results you see on the picture (taken with different microstep settings on the motors)
As you can see, in 1/4 step mode you clearly see all the steps of this motor and the cut is UGLY. 1/8 isn't better and from 1/16 and 1/32 I start to get better results.
its getting BETTER, but not yet good
The reason is probably because in microstepping mode steppers always tend to want to go into fullstep position. So if you are inbetween steps, you get actually not the wanted resolution but something inacurate.
I was looking at planetary gearboxes, but it seems like these would not be a good solution for me (I wonder why).
I was also considering using 0.9° motors and a 10:1 reduction between motor and axis by using 2 steel spur gears with 12 and 120 teeth.
And my last possibility is of course the most drastic one .... ballscrews.
Any ideas / hints / tips ?