Typically, most haunters wouldn't consider them due to the cost. Not only in buying the motor, but building/buying the controller it needs to make it operate. The controllers are pretty expensive unless you're rolling your own. Easily doubling, and in some cases quadrupling the cost, just to make the stepper motors work. They do have distinct advantages over servos though, namely higher torque, much more accurate (and repeatable) positioning. The downside vs. a servo is larger size, weight, cost, cost, and cost.


Although in the DIY controller realm, you can purchase the same basic controllers to work with either (arduino, polulu, and the like), but you'll have to add on H-bridge motor controllers specifically made to work with stepper motors for the stepper to function. More or less, it's too big a bother, and a bit to expensive for most to consider when compared to servos. But, perfect for robotics otoh.


The 60 steps/revolution, means that it has 60 different positions in one 360° revolution of the output shaft, or 16.67° turned per impulse from the controller. It's not very accurate for a stepper motor, as one that would typically be found in a CNC machine of decent quality, would typically be around 200 steps/rev. But it would be fine for prop use, where that type of fine movement control wouldn't be needed.


Hope that helps answer some of your questions.

 

I see them for sale all the time, but I didn't think they had enough torque for most props, since they aren't a gear motor. Or are they? I guess I just don't know enough about them.
I assumed they move in a "stepping" motion--like, click-click-click around in a circle. Yes? No?

 

Some are geared, and some aren't. The really high torque models usually are geared drive motors. Most of the time the gearing is external though, unlike the gear motors you're thinking of. But you can also increase the torque at low speed by wiring the coils in series, or you can increase the torque at high speeds by wiring the coils in parallel. Most people interact with steppers all of the time, and never realize it at all. The motor in your cd/dvd/bluray player or burner is a stepper. As are those in your hard drives, and your printer too.


They can step in singular steps like that, dependent on the digital signal given them yes. Or they can move in a perfectly fluid motion, and stop on a dime (& make change) at a very precise position. The precision of which, is denoted by how many steps/revolution in the motor rating, and whether that is capable of being broken down further into half steps & microstep's (half step/microstep's depend entirely on the driver controller, and hence why the prices vary so wildly on controllers. High precision costs oodles).

Omegamation makes a controller/driver, for instance, that is capable of dividing a 200 step/rev (1.8° per step, or a full step as it's known) to .007° steps. Which is 51,200 steps per revolution. Incredibly precise to be sure, but you lose torque by microstepping, being the trade off. As much as 30% of the motors maximum torque, in fact. Just an example of how accurate you can get with them, and not really super relevant to the discussion at hand. Impressive though, none the less.

 

Thanks for the info. Raven's Hollow. I guess I'd just have to buy a couple of them and experiment.

 

No problem, always happy to help With your track record with motorized props, I'm really interested to see what you have in mind

 

Thanks for the info Raven Hollow, looks like too much work and too expensive. Man I love this site so many folks so much knowledge.

 

Anytime disco, always a pleasure