# Build a DMX controlled Stepper Motor for cheap



## McCready00 (Dec 21, 2020)

Hello all, 

I am working on a small project with low budget. Yes, it's cliche to say so, but it is my situation right now. 

I need to control a motor with DMX. 

Option 1 / Best option : To control a step motor in order to move small and light piece of metal ( about 1/4 pound weight ) at different levels. 

Option 2 / That will work : That same piece of metal could be move from point A direclty to B using a motor, so no in between needed.

Anyone ever built one ? 

Any ideas ?

Thanks


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## dbaxter (Dec 22, 2020)

How accurate does the movement have to be? Is it something that just turning the motor on and having it run for 4.25 seconds is good enough or do you need to get to within 1/16 of an inch each time? Are you thinking of using a lead screw to go from rotation to linear position?


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## DrewE (Dec 22, 2020)

If you're looking for an off-the-shelf part, the closest I know of offhand are automated yokes for non-moving lights such as the Apollo Right Arm, which presumably could be rigged up to control something. That would be a relatively expensive way to go.

If I were attempting to do something like this, I'd rig up a microcontroller of some sort (an Arduino of some flavor is a convenient and well-supported option/ecosystem) to read DMX data and operate the stepper motor as desired via some sort of a stepper driver. That would not be particularly tricky to program, at least for someone with a bit of experience in such areas. DMX512 is a quite simple protocol to decode and interpret, and stepper drivers likewise pretty easy to work with. This could pretty easily be done for less than $50 from scratch, and probably a good bit less than that with a bit of shopping/scrounging around for parts.


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## JimOC_1 (Dec 22, 2020)

Would a DMX controlled mirror ball motor work?


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## microstar (Dec 22, 2020)

Northlight DMX sells a model airplane-type servo DMX control pc board.
Not sure how powerful a model airplane servo is for your application.


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## RonHebbard (Dec 22, 2020)

McCready00 said:


> Hello all,
> 
> I am working on a small project with low budget. Yes, it's cliche to say so, but it is my situation right now.
> 
> ...


I'm going to regret opening this can of worms, and reply with the following queries: 
1; How many steps per 360 degree rotation? 
2; Are you planning to rotate the stepper's shaft some number of full revolutions, stopping with step accurate positioning?? 
3; Is the end result lateral movement???
4; Is this a hoisting application????
5; Will your motor retain position underload????? 
5; Will your motor retain position if / when power is interrupted??????
6; (How much liability insurance are you carrying and is it paid up to date???????) 
*@What Rigger?* *@egilson1* *@TimMc* Care to comment / reply????????
Toodleoo! 
Ron Hebbard


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## Van (Dec 22, 2020)

McCready00 said:


> Hello all,
> 
> I am working on a small project with low budget. Yes, it's cliche to say so, but it is my situation right now.
> 
> ...


How low budget is "low budget" Fright Ideas has a DMX servo controller for $139. you could also build a DMX Stepper motor controller out of an Arduino or Raspberry Pi and a RAMPS board. or here's a link to a Q-kits thing that might work. the software interface might be tricky you might have to adapt something that would use g-code like you'd use on a 3d printer of CNC https://store.qkits.com/clone-ramps...-x-mega-3-x-mechanical-stops-with-cables.html


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## What Rigger? (Dec 22, 2020)

McCready00 said:


> Hello all,
> 
> I am working on a small project with low budget. Yes, it's cliche to say so, but it is my situation right now.
> 
> ...


@McCready00, can you give us the bigger picture? Moving 1/4lb load to what end? Is the end goal to lift this tiny load via what sort of lifting media- like a tiny winch?


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## TimMc (Dec 22, 2020)

RonHebbard said:


> I'm going to regret opening this can of worms, and reply with the following queries:
> 1; How many steps per 360 degree rotation?
> 2; Are you planning to rotate the stepper's shaft some number of full revolutions, stopping with step accurate positioning??
> 3; Is the end result lateral movement???
> ...


Nope. I know when to duck.


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## Joel Engelhardt (Dec 30, 2020)

I received for no cost an old ADJ moving mirror scanner. The LED did not work anymore, but everything else did--gobo wheel, pan, and tilt motors. I took all of the electronics out of the housing, and now I have (3) controllable stepper motors, which I can control easily over the existing DMX profile. All the electronics ran off of a 3A 12V DC power supply, so this is super easy to power using a UPS battery. 

If you feel confident in removing screws and disconnecting some cables, retrofitting an old fixture could be super inexpensive for you. Here is a used ADJ scanner on eBay for $60, and here is a Chinese moving head for $50. Do you think something like this could work for you?


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