Nema 17 choice
I am currently in the parts purchase phase for my second corexy (with my own design). Je vais utiliser une Duet Wifi paired with a Duex5 pour la controler. It will look very much like the E3D tool changer. It will have 2 hotends, 1 laser, 1 plotter (1 motor to lock the tool) and dual independent Z axis motor. My printer has a 500²mm frame with 400² motion limit (used with the laser) and a 300² heatbed. After reading the article about choosing stepper motors, I came to this result :
For the X/Y motion :
17HS16-2004S1 : 1.8° - 2.6mH - 2A - 45Ncm https://fr.aliexpress.com/item/32855316300.html
I don't think that the big brothers 17HS19-2004S2 with 59Ncm would be better ? Am I right ? https://fr.aliexpress.com/item/32994293330.html
For the Z axis and extruders, I was wondering if 0.9° steppers would be better. Because the Z axis/extruder speed are not really high, the motors would have more torque with the same angle lack and thus would be more precise ?
Do you have any other recommendation ?
Thanks in advance,
for the extruder you want to be around 400 steps /mm
this is normally achieved by using a 1.8 stepper with an 3:1 reduction, like in the bmg or titan.
for z 1.8degree steppers are fine. if you want finer resolution you can go with a different lead screw.
for example a 2mm lead screw with 1.8degree stepper gives 1600 steps / mm. more resolution that you normally need.
most people are fine with 8mm lead screw at 400 steps.
for x and y thats where you want 0.9 degree stepper motors. it does make a difference.
see this long thread. https://forum.prusaprinters.org/forum/original-prusa-i3-mk3s-mk3-user-mods-octoprint-enclosures-nozzles-.../stepper-motor-upgrades-to-eliminate-vfa-s-vertical-fine-artifacts/
for a good recommendation on motors i would refer you to this