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Nema 23 motors not following instructions

Setup on Lead CNC = Arduino Uno, CNC Shield V3, DVR8824. Using Easel to operate machine. When I go through the machine setup in Easel the X and Y motors work fine. The Y axis has two motors driving screws on each side. However when I press button to move Y forwards the Y axis moves forward if I press the button 4 or 5 times the axis moves forward 4 times and the one of the motors will go forward while the other one moves in opposite direction, twisting axis. When I press the button to move Y backwards this will happen 4 or 5 times, then one motor will move in opposite direction twisting axis. I have swapped wires as suggested in various sites but this has not solved the random change in direction of one of the motors. Help!!

To reverse a stepper you need to flip the “polarity” on ONE of the motor wire pairs.

Each stepper have four wires, which form two pairs, A and B. So you have A+/A- and B+/B-
So flip one pair around, to say A-/A+

If you are unsure which wires form a pair take a multimeter and measure resistance. If there is continuity then you have a pair.

Have done that and motors are still acting randomly.

If they are “randomly” then one of the wires have poor/no contact.

If one wire dont have contact the stepper will “step” as normal but direction will be random as directional control of the steps are lost.

Assuming there is nothing wrong with the gshield/DRV8825 drivers.

Thanks for that, I soldered all wire ends and put them into small elecrical connectors and all is working as should :grinning: :grinning: