Reply To: DRV8825 terrible at microstepping!?

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If you notice an issue I feel fast decay is the way to go.

The one thing that isn’t clear is how hard the stepper is being driven. If you run the stepper at max amps This is probably when this happens, You can hear the steppers they sound angry that is why I never run steppers at full power (and they get hot as hell). Regardless of driver being used.

We use smaller pulleys (for greater torque) which helps a lot. You can see the issue pop up in some 3D prints as a surface pattern (some people are using larger pulleys to try and gain a speed advantage which makes this worse). I am not sure if it is positional error showing up or the extruder stepper error. But to ease your mind the “jump” is less than half a full step but I will use half to make the math an over estimate.

We use 200 steps per mm of travel on the x and Y so each step is 0.005mm so the “error” would cause a positional difference of 0.0025mm at worst and is not cumulative. We use 4535.44 steps per mm (depending on leadscrew) so that error would be 0.00011mm.

In summary (hahah sounds official) If I did the math right and understand the article correctly, I would be super stoked if we noticed an error of that size, that would mean we have one hell of an accurate machine!

If you really want to have some fun I think I am going to be changing some recommended settings and Wiring in series (to my surprise) actually makes these steppers almost too strong. see here,