Often in Arduino or other electronic projects you may have a PCB or perfboard without an enclosure. This is a simple 3D printed custom enclosure you can model and make yourself without the need for much experience in either. This design is by no means super fancy or robust but it is simple to model, easy to assemble, cheap and for most hobby projects is likely suitable.
As part of the LED Matrix Audio Spectrum Visualizer the MSGEQ7 chips, their peripheral components and the two 3.5mm audio jacks were on a perfboard that wasn’t able to fit in the ATX PSU enclosure and needed its own separate box. The perf board was about 65mm by 52mm.
For this build I will be modelling the enclosure in 123D Design from Autodesk. 123D Design is specifically designed for 3D printing, is very intuitive and powerful enough for most things I’ll be doing, and it free.
The design of our enclosure will consist basically of a box with cutouts for connections and locations for two screw holes on opposite corners. The screw holes will be used to secure a plastic cover on top. The cover could be something fancy like acrylic or just some plastic from an old kitchen container, like what I’m using, to keep it cheap. The simple cover will provide some robustness but still be easy access and if you choose a clear material allow you to still see the electronics inside.
First, you’ll want to measure all the dimensions of your’re electronics board. This includes location of an external connector ports. I’d recommend getting a pair of calipers. I have this digital one, its inexpensive and they’ve worked well for me thus far.
With this enclosure, to keep it simple and avoid using extra screws and standoffs the enclosure will be carefully measured to snuggly fit the electronics board without needing any mounting components. The key here is giving tolerance to allow it to easily fit in the board while being relatively secure. It is very important to consider the extra length needed to insert the board in order to clear the enclosure walls as well as how the connectors or other tall components on the board will affect it. I made my board too short length-wise and hand to grind it down a bit to fit in.
Consider that if you’re electronics board has large connectors with bulk cables that will likely be connected/disconnected frequently this configuration isn’t ideal as the board will move slightly and not be secure to handle the cable stress. You can always add screw mounts to the bottom of the board.
Your electronics board may have different dimensions and connector ports so I’ll cover more generally the steps I took to make this and things to consider when designing your own. There are many ways to design in enclosure in 123D Design, this is just one approach. Here is decent introductory design manual on using 123D Design that maybe helpful.
After opening 123D Design, start by selecting the ‘Polyline’ under ‘Sketch’ and then making a rectangle for the area of your electronics, again consider extra space length-wise for fitting it in past the walls.
When using Polylines the highlighted parameter is first the length, once you enter you’re desired value and press ‘Enter’ it will be locked in, then you can enter the angle. Afterwards, select the end of you’re newly created polyline to add another one and so on to complete a rectangle.
In ‘Sketch’ select ‘Outline’ and select you’re rectangle. This will create the outer walls of the enclosure. I’d recommend at least 2.5mm walls. I made mine 5mm as this would give more space for the screw holes.
Now, again using ‘Polyline’ I created the extra area on opposite corners for the screw holes, basically a 10mm square at the corner.
Do the same on the opposite corner and then connect the corners to make sort of a parallelogram. Of course you can always add screw holes to all corners if you wanted to make it more robust.
In ‘Construct’ select ‘Extrude’ and select all of the elements that will serves as the side walls. Extrude them up to you’re desired height. Make sure you also include the height of the floor thickness.
Now extrude the floor. I made mine 2.5mm.
Now we’ll add connector ports. This will obviously differ based on your project but the principal is the same. I used ‘Polyline’ and then selected the inside back wall of the enclosure to change you’re working plane. Then I used the inside corner edge as a reference and measured out the correct distance of where my connector should be and created the cutout. Double check you’re connector measurements to ensure correct placement and fit.
For the image below I’m just making a small cutout to fit a ribbon cable through. This will be sandwiched between the cover when its added.
Now I did the same for my other connectors. These are 3.5mm audio jacks.
Once your cutout dimensions are created select ‘Extrude’ and highlight the cutout region and ‘Subtract’ out the area from the enclosure walls. With the 3.5mm audio jacks, in order to allow space for plugs to fit in, I added a bevel angle to the extrusion.
The last thing to do it is add screw holes. There are many ways to do this in 3D prints, this article highlights some of the common ways to do so with their pros and cons. For this project, I made the screws holes fairly small at 1.5mm and then using a soldering iron melted them a bit and inserted machine screws to make my own threads.
I don’t have my own 3D printer as of yet so I used a 3D print service. I’m a fan of www.3dhubs.com. All you do is upload you’re .STL file and your location and it gives you a list of 3D print services in your area as well as their material and resolution options, estimated cost and shipping and reviews. If you are student you also get a decent discount.
I ordered mine in PLA with 200 microns layer height. I was really impressed with the quality of my print and the price was fairly reasonable including shipping. For the occasional project this worked well although if you start doing many prints this way it can get expensive. I’m hoping to get myself a 3D printer in the future but in the meantime 3D print services are a great way to get familiar with modelling and a way to get great quality prints without owning an expensive printer yourself.
Now you find out if you measured correctly. As I mentioned my length dimension was a bit too short to fit the board in so I had to sand down the board length a bit to fit it in. Be careful not to get your board stuck in the enclosure either with this friction fit mounting design. It may be a good idea to add or drill a hole in the bottom so you can push the board out from the bottom if needed.
For the cover I cutout a piece of plastic from old kitchen container and cut it to size and drill holes to mount it. To make the screw holes I took a soldering iron and inserted it in the screw holes I made to melt the plastic a bit and immediately screwed in a M3 screw to make rough threads for it. This approach was simple and sort of worked but likely won’t hold up to much repeated removal.
There you have it, a super simple enclosure for your electronics boards! Now I have a nice little enclosure for my peripheral board on my LED Matrix Audio Spectrum Visualizer project.
Overall, for a simple and easy to make 3D printed enclosure I was very happy with this build. Some things I would consider in the future though would be:
- Using board mount standoffs to secure the board.
- Making a better cover. The current plastic looks like crap to be honest. Using acrylic or nicer plastic would have looked much better. You could even 3D print one for it.
- Improved screw threads for the cover. I’d like to explore different and more robust techniques to do this.