Build Your Own SLA/SLS

Hello. I'm new to the forum - thanks for all the great advice in my reading so far.

I'm gathering supplies for DLP-based 3D printer build and have run into a stepper motor problem. A friend has given me a ballscrew actuator with a 12" travel and 5-phase 500steps/rev stepper motor (very nice of him). However, due to the wiring configuration of this motor, I'm having trouble figuring out how to connect it to my RAMPS 1.4 board. Unlike most 5-lead motors, this motor contains 5 coils which are arranged in a pentagon configuration.

The motor information and wiring diagram can be found here (see "more images"):



As an alternative to using the RAMPS 1.4, this actuator also came with a CRK-series stepper motor driver. Is there a way to control this with the Arduino or RAMPS 1.4 setup? Can CW send commands to the CRK via USB?

What are your thoughts on this? Should I look into getting a more compatible stepper?

Hi, welcome to the forum.

Firstly, ask too because there are way more people there who are familiar with RAMPS and I'll bet you'll a get a better answer there. Although, there is a growing number of highly competent forum patrons here too so lets see what they have to say. As for my answer, easy, replace it with a bipolar NEMA 23 stepper and you're done. The good thing is they are standardized so another NEMA 23 will bolt right into your linear way without a hitch, just need to make sure the shafts are identical in diameter and length. Making sure to stay within the electrical power rating of the RAMS driver as well.

On the other hand, with your RAMPS board you'll notice that there are 5 receptacles where you can plug in stepper motor drivers. As you've learned those drivers are not compatible with your stepper motor, however, you have a driver that IS compatible with your motor. So, what you could do is find out what pins on a RAMPS board driver receptacle correspond to step and direction and then connect those pins to your step and direction pins on your driver that you have for your motor. If you figured out how to do this all you would need is a power supply for your stepper motor driver and you'd be up and running. Or, you may even be able to tap power too from your RAMPS board to power your driver depending on what the voltage and power rating of your driver is. As for a driver that would plug in to your RAMPS board that will work with your motor I think that's going to be unobtainable. Those motors are kind of on the rare side.

Thank you James,

We took the easy route, due to time constraints, and ordered a NEMA 23 stepper. Works great with the RAMPS as expected! I had one small hiccup, since the bolt configuration of the NEMA 23 oddly didn't match the configuration on the Vexta motor we replaced; however, making a plate to accommodate this only took a few hours - will try it out the full assembly tomorrow. We also ordered a different coupler due to a smaller shaft size - $5.

Time-permitting, I'd still like to control the Oriental Motor CRK-Series stepper driver with the RAMPS 1.4 if possible. This way, we could take advantage of the motor's resolution and torque capabilities. It's the Pentagonal wiring configuration that's throwing me off - found .

Thanks again.