New Nema 17s for Z Axis Not Working

AQhatesA5S

Hi there, having so much fun with my A5S (he says sarcastically). I swapped out the Z axis lead screws (they were bent) with 2mm lead version. Not enough torque in stock steppers to handle so "upgraded" to new Nema 17s from TwoTrees:

https://www.amazon.ca/gp/product/B08C2KDY6R/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

I assumed it would be a straight swap as they are both 4 pin but neither seem to be powering on/turning.

X and Y axis are working, just not the Z.

Can someone please advise what I am missing?

Thanks!

PS lots of great information on this forum for which I am very grateful!

michalko99

compare coils on both motors-old and new. use multimeter with Ohm setting. If you look in picture of your link, you will see how coils are connected in new motor. Maybe original has used different pins. They should be around 3Ohms. Measure with unplugged cable.

I think that A5s has 2mm screw from stock. At least my A5 is 2mm. There is something wrong with assembly, as motor should need less torque with 2mm screw and higher torque with 8mm screw(talking about pitch)

Samuel Pinches

Hi @AQhatesA5S ... unfortunately, it's not just a matter of motor power, it is also a matter of stepper motor driver power. The drivers on the A5S are fixed, so it is not possible to increase their power etc. I know its not what you want to hear, but I recommend finding a matching pitch to the original lead screws. You may also try adding greater lubrication.

However, if they are not turning at all, then the wiring may be wrong.