I think my Monoprice Select Mini (MPSM) v2 3D printer is excellent: quite inexpensive but capable of good quality prints using a variety of filament materials. It’s also got a nice big back-lit display that tells me lots of useful information, including things like nozzle and bed temperatures, which is great. However, one aspect I decided could be improved on was the power supply, as the power switch is around the back so a bit awkward to get to.
So I decided to build a small console to sit at the top of the printer column with a power switch that was easy to access. And while doing that I thought why not also add some 5V USB sockets to run cheap lighting and fans off? Of course, that sort of thinking leads to ‘why not add a small power meter too?’ so I added one, plus a small tool holder as well to keep things like bed-levelling hex keys, and small files, organised. Below is a photo of the finished console with a cheap USB light running off it.
I find it very useful. For one thing it’s easy to turn the printer on now and another advantage is that I can see how much power is being used and monitor it for changes that might indicate problems or maintenance needs. And while the power circuit I used for the 5V USB sockets is very simple and not recommended for powering anything expensive, it’s very handy to be able to turn on a work-light powered by the printer. It was also very simple to make, using just five parts that need 3D printing, as shown in the exploded diagram below. All of these parts are freely available to download: click here to go to the MyMiniFactory page to get them.
Once the parts are printed I found it best to build the circuit inside the shell first, as the sides will get in the way if glued on in advance. I’ve included a circuit diagram of how I built the console below. Although I’m sure it could be improved in many ways it provided a good starting point for me. Basically it comprises a 30V power meter and a few switches, together with power sockets and a simple voltage regulator circuit.
Obviously a bit of soldering experience was needed, but it wasn’t too onerous. Mostly it was just a case of running wires between things and soldering the ends. In the case of the thicker connections in the diagram I made sure I used the wires built into the meter all the way to the sockets, as they’re made for higher current than normal smaller diameter wires. Also, that’s why I used a number of wires in parallel for the connection between the sockets through the power switch. Similarly, the cables used to go from Vout in the diagram to the 3D printer power socket needed to be thick enough otherwise they get quite hot. And to show how I fitted it all together below is a photo of the inside of the console.
Having done all that work, and tested the circuit, the side panels were glued onto the shell, as well as the tool holder. The two cutouts in the tool holder were used to glue in a couple of 25x10x3mm rare earth magnets. They’re very strong and can be used to hang small tools on the back of the console where they’re easily accessible. Then the base connector was simply screwed to the top of the printer console, using the two small screws already there. That allowed the console to be slid on using the slots at each side. It held in place quite well, but I included a couple of small screw holes at the ends to make it more secure. Then after wiring up the power cables the project was finished and ready to enjoy 🙂