Stepper Motor for 3D Printer

25, May, 2013

What stepper motor are you using in your 3d printer?
NEMA17 steppers are the most popular choice as a reprap stepper motor. But are you just a follower?

What is a good source of affordable stepper motors for a reprap printer?
Reprap Wiki has a list of NEMA14 and NEMA17 stepper motors for 3D Printers.
Besides price consideration, what do you need for your 3d printer building, a Nema17 stepper motor?
1. 5mm flat shaft motor is most popular and you could find pulleys(GT2, MXL or T2.5) for it easily. A single flat shaft 5mm is good choice for the extruder, and you can find there are many sources of no matter NEMA14 34mm or NEMA17 34mm, 48mm and 60mm steppers.
2. 4 lead wires as long as possible. 700mm lead wires w/ both connectors for Motor and Electronic Boards(RAMPS 1.4 or Gen 6.0) are recommended.
3. The motor supplier can supply you with T2.5 16 gears Pulley, MXL 18 tooth Pulley or GT2 20 teeth Pulley in the same time.
4. Threaded rod NEMA17 stepper motor can be supplied in the same time for your Z axis.

RobotDigg(GTW Motor) bring 4 stepper motors for 3d printers online, they are:
NEMA14 34mm long, 0.8A 15N.cm or 1.25A, 9N.cm. You may have questions on this why lower Rated Current has more power. 14N.cm, 15N.cm or 18N.cm holding torque nema14 steppers perform much better at low speed 100rpm. 1.25A nema14 stepper has more torque output than 0.8A nema14 stepper at high speed 300rpm as example.

RobotDigg have three nema17 steppers are great option for your 3d printer: NEMA17 34mm 0.8A, Nema17 40mm 1.2A 0.4N.m and Nema17 60mm 1.5A 0.65N.m
Reprapers or 3d printer stores are chasing high torque/large torque nema17 steppers, BUT do you really need a much more powerful stepper motor for your 3d printer or just a handy nema14, nema17 stepper is enough? A 0.44N.m stepper is better than 0.4N.m? RobotDigg would tell you that the answer is definitely NO.

How to choose a stepper motor?
Engineers read Torque Curves. Reprapers use experience and follow others.
NEMA14, NEMA17 34mm stepper motor for Huxley. NEMA14 48mm 0.44N.m for Prusa Mendel.
RobotDigg creat.