As if this has never been done before! Anyway, in Part 6 of Making Movies I wrote about the slider that I’d bought and noted that I was considering turning it into a motorised slider so that I could get more controlled and smoother motion. What I was achieving wasn’t too bad, but I could never quite get consistent motion across the full length of the slider and that started to become very frustrating. That convinced me even more that I needed to add a motor to the slider. But what really prompted me was when I decided to dismantle one of my old printers, salvaging any useful parts that I could remove, I came across a number of bits and pieces like motors, belts, brackets, as well as hundreds of small screws. That spurred me to start looking at converting my slider to a motorised one, given the parts that started to pile up.
Initially I thought I’d be able to get everything from the printer parts but, unfortunately, the motors were all stepper motors and I was in no mind to start building a controller for these (and first learning how to do that), so I decided to go very basic and get a few things from eBay. First off, I found a nice reduction-gear motor for $27 that was perfect for the task and then came across a nifty 10-60V 60A controller to suit for $14. The main belt from the printer was unfortunately way too short for the slider, so again I went to eBay in search of alternatives and came across a 3D printer timing belt and pulley package with 10m of belt and 10 pulley wheels for $18. And so with bits and pieces from the printer and some other stuff from my shed, I had everything that I needed and was able to assemble a pretty neat solution for motorising the slider.
With a bit of luck, which doesn’t happen often, the motor mounting holes aligned perfectly with the holes in the slider, so all I needed were two screws to fit the motor and it was very solidly mounted. The idler pulley was a little more problematic, but eventually I found a solid bracket in my shed that was easy enough to modify and fit to the other end. The pulley wheel is mounted to a dead motor from my MJX Bugs 3 drone and turned out to be ideal for the job. I was pondering using just a bolt and nuts, but the motor was a nicer looking addition. The belt, on the other hand, was a bit of a pain to get right, especially finding a way to locate it so that it wouldn’t interfere with the travel and was solidly mounted. I ended up using some metal I had lying around and a Rivnut screwed into a bolt to hold the belt in place, but getting the tension right was a frustrating affair, until I hit upon using some heat shrink to hold the belt in place and keep it tight. With this setup, I can easily lift the belt off the Rivnut and make the slider fully manual once again.
Once that was done, it was time to add the motor controller. While I could have powered the motor using a 240V adapter, I decided to use one of the batteries from the MJX Bugs 3 drone. One thing that I couldn’t quite figure out was how to easily reverse the power so that I could move the slider head backwards and forwards. I was about to get a double-pole, double-throw, switch, but then thought an easier option was to just use two balance plugs from a pack I had for my drone, which would power the motor and and allow me to connect them to the controller in reverse polarity. All I had to then do was just swap plugs to suit whichever way I wanted the motor to turn. Maybe that’s a somewhat inelegant solution, but it’s simple and works fine and I can’t imagine a situation where you need to change directions in an instant. Finally I had to decide what I was going to do with the battery and controller, as I couldn’t just let them hang freely with no support. So another piece, or pieces, from the printer came to the rescue and I was able to make a platform to hold the controller and battery. Using 3M dual lock, both the controller and battery would stay firmly in place yet be easy to remove as needed.
The motor is a 5-250 rpm unit and with the controller gives me a range of speeds to suit just about every situation, and even though the battery is only 7.6V (fully charged 8.4V), it powers the motor without any trouble at all. The only issue I have with the motor is that in one direction it’s a tad noisy (I don’t know why), but I don’t think that I’ll be using it in situations were the noise will be a major problem and if it does become a problem, I might have to look at another motor option. In any case, I’m more than likely going to be overriding it with other sounds. By using a battery, the slider is now fully portable and can be used anywhere without having to worry about a power source. And because I’m using batteries from my MJX Bugs 3, which goes with me on my bush trips, I will always have a battery on hand. This is how it works (note that I can vary the speed a lot more than just the two speeds shown) :
As a final note, I’ve watched quite a number of videos on motorising a commercially made slider and all too many have involved complex electronics building (Arduino and whatnot) and machining or 3D printing as a starting point. I just wanted to avoid all such complexity and, as you can see, my build wasn’t rocket science and cost less than AU$60 dollars for all the major parts that I had to buy; motor, controller, belt/pulleys and you can add a bit more if you don’t happen to have bolts etc. And I saved a hell of a lot as I was seriously pondering getting a TurnsPro motor/controller (often noted as a great controller for a slider) which, on its own, would have cost at least three times as much as my entire project. In Part 8 of my Making Movies story, I cover how I use the slider in its motorised form, especially with a gimbal.