How important is torque for stepper motors on 3D printer? Adafruit has Nema 17s that are the shorter length and have about half the torque (and price) of a kysan nema 17 42mm.
Sorry for my ignorance, I don’t have an engineering background.
How much? Maker Farm sells some for $15. I have seen some for $35. The maker farm ones are supposed to be 0.5A with 60oz in holding torque.
Torque has to be high enough to avoid skipped steps because most 3D printers do not have a position feedback system. The holding torque needs to be high enough to avoid losing the position when you bump it.
On the extruder needs decent torque. Depending on the design. Some recommendations are here.
If you’re talking about these: http://www.adafruit.com/product/324 - Then they’re completely wrong for our purposes. 35ohm motors, YIKES! You’re looking for something in the 2-4v range, 1-4ohms, and 3+ Kg.cm
Ok thanks @ThantiK Appreciate it. I was referred to that motor and had my doubts.
I may be wrong but I have my doubts about the $14 motors at MakerFarm. I would buy their $15 ones. I do not know of another cheap motor that may suffice. If I did, I would tell you about that too, but sadly I do not know many cheap sources.
Here’s what I look for in a general-purpose (trypically X, Y and Z; extruders have different needs) NEMA17 stepper motor:
4kgcm minimum (~55 ozin, use this tool to convert the various units: http://www.numberfactory.com/nf_torque.html)
4V rated voltage maximum (assuming a 12v supply, if there’s no voltage rating listed, you can calculate it from the current rating and phase resistance using Ohm’s Law)
2A maximum (less with some stepper drivers)
$14 each maximum (in single-quantities, if you’re buying more than 10, shop around for a vendor with a better base price and a bulk discount)
If the motor is being carried around by the X or Y axis, its mass is also an important consideration. Of course, you don’t want to be any closer to these minimum/maximum values than you need to be.
https://www.massdrop.com/buy/nema17-motor $10 a pop so if these will do, I’m ordering a good amount. checks out based on your list @Whosa_whatsis
@Ben_Van_Den_Broeck those are good motors.