Just did some testing over the weekend and googling of torque curves of stepper motors and max rpm. Probably a no brainer for some of you, but really taught myself something so figured I would share it or at least post it here for my future self lol.
So its always a give and take relationship when it comes to speed and accuracy we all know that. My problem more recently has I upgraded my X-Axis to a higher gearing to give me more accuracy. Well the trade off to that is that the motor has to spin at higher rpm's to move the printhead. So this is where my knowledge of stepper motors was lacking. So with stepper motors as the rpm increases the torque of the motors drops off almost a cliff a very steep drop off from nearly full torque to hardly anything. So what happened to me was it would accelerate and then stop and start skipping around.
These numbers are not real at all but just giving an example of how the torque curve matches the rpm and practical outcome.
Nema 17 68oz torque Max rpm 1000 Motor stalls at 200rpm because the torque at 200rpm is 10oz not enough to keep the printhead moving.
Nema 23 172 oz torque Max rpm 500 Motor stalls at 350rpm because the torque at 350rpm is 10oz not enough to keep the printhead moving.
So although the Max rpm of a Nema 23 is lower it can move the printhead allot faster. There are big trade offs when it comes to weight so not simple solution but it helped me figure out the math on my latest project.
Edited 2 time(s). Last edit at 10/31/2016 03:32PM by AquaticsLive.
