Ok I have been musing on this one for some time. Having bought a outrunner type BLDC and stripped it down to have a look at it, I was quite amazed at how simple they are. Arguably more simple than a brushed DC motor. Perhaps even simple enough to print...... https://reprap.org/forum/read.php?160,37334,37334#msg-37334 Fri, 17 Apr 2026 12:17:12 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?160,37334,50499#msg-50499 https://reprap.org/forum/read.php?160,37334,50499#msg-50499 body of work. :D

... You realize that now I'm going to have to set aside a few hours and read all this stuff. :)o]]> SebastienBailard Stepper Motors, Servo Motors, DC Motors Thu, 01 Jul 2010 03:11:41 -0400 https://reprap.org/forum/read.php?160,37334,50495#msg-50495 https://reprap.org/forum/read.php?160,37334,50495#msg-50495
I started a wiki review article on Actuator Fabrication that you might be interested in:
[www.reprap.org]

Many of you will be familiar with most of the information, but I would wager that even the most grizzled old replicators among you might find something new.

Please visit and add your own contributions!

-Matt]]> MattMoses Stepper Motors, Servo Motors, DC Motors Thu, 01 Jul 2010 01:46:18 -0400 https://reprap.org/forum/read.php?160,37334,42767#msg-42767 https://reprap.org/forum/read.php?160,37334,42767#msg-42767
The weak part of DC motors (or universal motors) is the brushes. I guess this is specificaly why I was thinking along the lines of BLDC's ie, Brushless DC. Alignment, metarials and reliability are all issues with brushed motors.

Electronic commutation is reliable, fast and has a side benefit of producing a useful degree of position & speed sensing.

Copper these days is expensive, steel is cheap and permanent magnets are farily common.]]> aka47 Stepper Motors, Servo Motors, DC Motors Fri, 16 Apr 2010 13:03:10 -0400 https://reprap.org/forum/read.php?160,37334,42754#msg-42754 https://reprap.org/forum/read.php?160,37334,42754#msg-42754 xoid Stepper Motors, Servo Motors, DC Motors Fri, 16 Apr 2010 10:33:50 -0400 https://reprap.org/forum/read.php?160,37334,42752#msg-42752 https://reprap.org/forum/read.php?160,37334,42752#msg-42752
It is good idea to make one!

Rotor and stator will both consist of wire coils. Wire on plastic frame. That is all. So we need brushes to power rotor. Brushes may be commutating (usual DC) or not commutating (just two rings) - but at this case you need smart controller to swith fazes.]]> xoid Stepper Motors, Servo Motors, DC Motors Fri, 16 Apr 2010 10:04:57 -0400 https://reprap.org/forum/read.php?160,37334,37804#msg-37804 https://reprap.org/forum/read.php?160,37334,37804#msg-37804
Certainly close enough for the purposes at hand. Given that they are mechanically simpler than a stepper though (as you pointed out less poles) they should be easier to make.

Particulalry the out-runner style.

I have a cheapish one I bought in to dismantle and there is very little to them electro/mechanically.

Certainly the plastics are printable and the out-runner could be made from cheap steel pipe section.

The benefits of the out-runner are that they generate more torque and the magnets are constrained against centrifugal force by the steel pipe section.

Minaturisation is'nt really an issue for what we are trying to achieve motors that are of a reasonable size with good torque are what we want.]]> aka47 Stepper Motors, Servo Motors, DC Motors Wed, 03 Mar 2010 15:38:39 -0500 https://reprap.org/forum/read.php?160,37334,37732#msg-37732 https://reprap.org/forum/read.php?160,37334,37732#msg-37732
They closely resemble stepper motors with maybe 12 steps per rev, and 3 coils in a delta or wye configuration instead of two separates.]]> Triffid_Hunter Stepper Motors, Servo Motors, DC Motors Tue, 02 Mar 2010 19:28:42 -0500 https://reprap.org/forum/read.php?160,37334,37334#msg-37334 https://reprap.org/forum/read.php?160,37334,37334#msg-37334
I have been musing on this one for some time. Having bought a outrunner type BLDC and stripped it down to have a look at it, I was quite amazed at how simple they are.

Arguably more simple than a brushed DC motor.

Perhaps even simple enough to print......]]> aka47 Stepper Motors, Servo Motors, DC Motors Thu, 25 Feb 2010 19:39:54 -0500