I am currently looking for which stepper motor to get for my reprap. My problem is that apart from knowing it needs to be a NEMA 14 or 17 or 23 (I am choosing nema 17) not much other information can be found. for example would this be ok stepper 6 wires even with 6 wires? or should it be something like also 6 wire or 4 wire because it seems i am able to get the 6 wire slightly cheaper then the 4 wire ones like the one from maker bot. Also does the size matter the last 4 wire stepper is a lot larger then the others and am wondering would weight be a problem. i understand it probably would for the extruder. https://reprap.org/forum/read.php?160,43048,43048#msg-43048 Mon, 16 Mar 2026 01:22:50 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?160,43048,47398#msg-47398 https://reprap.org/forum/read.php?160,43048,47398#msg-47398 dissidence Stepper Motors, Servo Motors, DC Motors Sun, 06 Jun 2010 20:02:11 -0400 https://reprap.org/forum/read.php?160,43048,47372#msg-47372 https://reprap.org/forum/read.php?160,43048,47372#msg-47372
[www.stepgenie.com]

i've used them and they are fantastic. no overheating what-so-ever. well obvisouly because the mosfets are running way below what they are capable of.

however only half step mode at most, i've used current limiting resistors with good success but getting really high speed will be an issue without a 'chopper drive'

here is another site from a guy that frequents cnczone.com

[pminmo.com]

some cool circuits that will peak someones interest.]]> lunchtrayrider Stepper Motors, Servo Motors, DC Motors Sun, 06 Jun 2010 15:15:21 -0400 https://reprap.org/forum/read.php?160,43048,46626#msg-46626 https://reprap.org/forum/read.php?160,43048,46626#msg-46626
If you use the whole winding you have to drop the current by sqrt(2) so that the total power is the same. I.e. power is I^2 R and you have double R so have to reduce I by 70%. Torque is proportional to current times turns so you get 40% more torque. Power is the same so your motor has become 40% more efficient as bipolar motors are.

Inductance is proportional to turns squared so will be four times bigger causing torque to fall off with speed 4 times faster.

So for slow moving high torque (extruder conditions) full coil might be better but for fast movement half coil is better.]]> nophead Stepper Motors, Servo Motors, DC Motors Fri, 28 May 2010 11:03:42 -0400 https://reprap.org/forum/read.php?160,43048,46619#msg-46619 https://reprap.org/forum/read.php?160,43048,46619#msg-46619 Stefan Stepper Motors, Servo Motors, DC Motors Fri, 28 May 2010 09:49:56 -0400 https://reprap.org/forum/read.php?160,43048,45366#msg-45366 https://reprap.org/forum/read.php?160,43048,45366#msg-45366 nophead Stepper Motors, Servo Motors, DC Motors Wed, 12 May 2010 17:29:59 -0400 https://reprap.org/forum/read.php?160,43048,45354#msg-45354 https://reprap.org/forum/read.php?160,43048,45354#msg-45354
i will have to look into them a little more,]]> dissidence Stepper Motors, Servo Motors, DC Motors Wed, 12 May 2010 12:34:10 -0400 https://reprap.org/forum/read.php?160,43048,45309#msg-45309 https://reprap.org/forum/read.php?160,43048,45309#msg-45309
As far as I know, micro-stepping and current control does not work as well in unipolar mode. I think one can half step. The drivers I have seem to exhibit a resonance point which limits the useful speed.

A unipolar driver can be made with about 3 TTL/HC chips and 4 transistors that switch to ground. My piano roll scanner works with a simple Unipolar board.


-julie]]> sheep Stepper Motors, Servo Motors, DC Motors Wed, 12 May 2010 02:33:11 -0400 https://reprap.org/forum/read.php?160,43048,45289#msg-45289 https://reprap.org/forum/read.php?160,43048,45289#msg-45289
i do wish there was more information out there has to what kinda torque you need on your stepper if you want to use a geared extruder]]> dissidence Stepper Motors, Servo Motors, DC Motors Tue, 11 May 2010 19:42:42 -0400 https://reprap.org/forum/read.php?160,43048,43621#msg-43621 https://reprap.org/forum/read.php?160,43048,43621#msg-43621 5 wire motors are only unipolar (which won't work)
6 wire motors can be wired in bipolar series (which works just fine) or unipolar (which wont work)
8 wire motors can be wired in bipolar series (which works just fine) bipolar parallel (which will work but the amp draw requirement is high, make sure it would be less then 2 amps, otherwise wire in bipolar series) and unipolar (which won't work)]]> lunchtrayrider Stepper Motors, Servo Motors, DC Motors Sun, 25 Apr 2010 01:56:49 -0400 https://reprap.org/forum/read.php?160,43048,43412#msg-43412 https://reprap.org/forum/read.php?160,43048,43412#msg-43412
If they stay separate, we definitely need to get all the units sorted out. I'll have a go at it when I can.]]> Cefiar Stepper Motors, Servo Motors, DC Motors Wed, 21 Apr 2010 21:04:51 -0400 https://reprap.org/forum/read.php?160,43048,43404#msg-43404 https://reprap.org/forum/read.php?160,43048,43404#msg-43404 There is another Mendel-specific page with requirements along with links to specific motors+suppliers and if they're tested or not.

Basically what you want is a
- bipolar (4 wire, or 8)
- 1.8 degree or 200 steps (minimum)
- roughly 14 N-cm torque (minimum)
- 5mm shaft.

Many NEMA 17's will fit this bill. NEMA 14 generally will not be strong enough or if they are, run hot because they're being driven at a higher duty cycle. NEMA 23 will be overkill and I'd be a bit concerned over the extra weight.

There are some other factors to consider such as phase resistance and therefore how much current and voltage the motor can handle. There may be some odd low-voltage motor or something that would burn up or draw too much current, but most of the commonly-available steppers will be fine.

Depending on which extruder design / motor pulleys you will be using, it can be advantageous to have various shaft geometries - single flat, double flat, splined, etc.

[reprap.org] - Darwin stepper motor page, has wiring information

[reprap.org] - Mendel stepper motor page, lists a bunch of known-working motors and links to suppliers]]> Nyarlathotep Stepper Motors, Servo Motors, DC Motors Wed, 21 Apr 2010 18:01:51 -0400 https://reprap.org/forum/read.php?160,43048,43337#msg-43337 https://reprap.org/forum/read.php?160,43048,43337#msg-43337
A 4 wire motor only works with a bipolar driver board. 6 and 8 wire motors can be wired to work with bipolar or unipolar driver boards.]]> madscifi Stepper Motors, Servo Motors, DC Motors Tue, 20 Apr 2010 23:08:02 -0400 https://reprap.org/forum/read.php?160,43048,43048#msg-43048 https://reprap.org/forum/read.php?160,43048,43048#msg-43048 stepper 6 wires even with 6 wires?
or should it be something like
also 6 wire
or 4 wire
because it seems i am able to get the 6 wire slightly cheaper then the 4 wire ones like the one from maker bot. Also does the size matter the last 4 wire stepper is a lot larger then the others and am wondering would weight be a problem. i understand it probably would for the extruder.]]> dbhellmith Stepper Motors, Servo Motors, DC Motors Mon, 19 Apr 2010 21:28:47 -0400