Arduino Enclosure
This is my make-through for a 3D printable Arduino enclosure so grab a cup of coffee and let's get started!
Process Map
Background
What's Our Goal?
This was our first session after finishing the first iteration in our game controller module and its sole purpose was to practice creating a 3D printable snap-fit design in order to prepare for our next iteration which will involve redesigning our game controller with 3D printable parts. Thus, we decided what could be better than designing a protective case for our Arduino Leonardo board.
So let's have some fun designing!
Machines and Programs
We Won't Be Needing Much Here
We'll just be using the following:
Machines:
A 3D printer
Software programs:
A CAD software such as Fusion 360
A 3D printing software such as Ultimaker Cura or MakerBot Print
Designing on Fusion 360
Let's Design our Enclosure
The first part involves designing our enclosure on Fusion 360. Our design will involve two parts that will snap together around the Arduino for protection while still providing access to all the Arduino connectors.
Sketching
Top View Sketch
The first thing I did was import an Arduino Leonardo model into Fusion to get its dimensions and accordingly design the enclosure. I did one main sketch from a top view that had almost everything needed to create the design. I projected the Arduino's dimensions along with its power jack, reset switch, and pins with a clearance of 0.5mm for everything.
Next, I created the borders that'll be used for the design. You'll see that there are several rounded rectangles drawn. The two outermost rectangles are common for both the bottom and top parts. The two innermost rectangles though are just for the top part to create an inner wall. This will actually be much clearer when we get to the top part.
Side View Sketch
So technically the top view sketch was enough to create most of the design. However, we still needed to have two side openings for the power jack and USB port and that was part of a side view sketch.
Then there was the snap fit left. This was part of the side view sketch as well that just involved a rounded triangle. No wait, two rounded triangles actually with a 0.3 clearance between them. Why? I'll tell you why but try to use your imagination here. The innermost triangle will be an extruded join with the top part while the outermost triangle will be an extruded cut with the bottom part. This might become clearer when we get into more details below but for now we just need to know that these were the sketches created. The clearance here was just so that the parts can fit smoothly against each other.
Bottom Part
To create the bottom part, I extruded the two outermost rectangles from the top view sketch. Then, I extruded the power jack and USB port from the side view sketch to cut through the part from the side as shown. What was left was the snap fit which as mentioned above was created using an extruded cut. I did one and simply mirrored it to the other side using a midplane. I also decided to extrude the holes from the Arduino board at the bottom part in case we needed to mount the enclosure when using it in a project later on.
Top Part
I extruded the two outermost rectangles from the top view sketch as well to create the top part. However, the height here is much smaller than the bottom part. Also, notice the inner wall here? That was why we needed the two innermost rectangles as mentioned above. After that, it was extruding the power jack, reset switch, and pins to cut through the part from the top. I extruded the power jack from the side view sketch to cut through the part from the side as well. Finally, I created the snap fit in a very similar way to the bottom part except that it was done using an extruded join instead.
Assembling the Enclosure
After assembling both parts together with the Leonardo board in place, this how the enclosure will finally look like.
Preparing for 3D Printing
Once we are done designing, we export each part as an STL file. We keep the default format as binary since it is the most recommended for 3D printing and choose refinement as high. High will give a higher resolution through more triangles.
3D Printing
The Awaited Part
All what's left now is to print our parts. We open the STL files we saved from Fusion 360 on Ultimaker Cura from the first button in the stage menu. We then choose the 3D printer model to be used from the second button which in my case was Prusa i3 MK2 and the printing material from the third button which I chose to be PLA. The last button contains the print settings that could be changed but I left most settings as default. I just changed the layer height to be 0.2mm and the infill to be 20%.
Now that the printer type, configuration and print settings are all set, we slice the model from a button in the bottom right corner. When the process completes, it will show a preview button which will take us to the preview stage. The preview is ideal for seeing what the inside of our print will look like and how it will be printed. We’ll also get an estimated print time and weight based on the material we selected earlier.
Once we are happy with preview, we click the “Save to File” button to get a G-code file that'll be opened on the 3D printer to start the printing process.
Arduino_Enclosure_3D_Printed.mp4
Trying it Out
Too Good To Be True
This was a one shot trial so if the design didn't out to be right from the first time, sadly I wouldn't be able to print it again.
So actually I would say that this was a complete success and everything turned out as expected if it wasn't for one tiny thing I didn't account for which was the USB opening. The Arduino Leonardo's USB type is micro and I had the port size opening to be an exact fit. This wouldn't be a problem if the USB tip was the long size, 8mm-9mm. However, most of the USBs in the market have the regular size, 5mm-6mm. Thus, when inserting the regular sized USB, it wasn't able to go all the way through the port. But to be honest, I didn't expect it to turn out flawless from the first time so for a first trial, I would could consider this a good output. Plus, we could look at the bright side which is that the snap fit was a really good fit and that was after all the purpose of this whole design.
Conclusion
The Design Possibilities are Endless
This design is just one of many other possible designs. For instance, we created our design using a cantilever snap fit but you could use another type of fit or place the fits somewhere else in the design. You could even use a different material when printing. You could create a laser cut design instead of a 3D printed one. The possibilities are just infinite and it may even take a lot of trial and error to create something that both looks good and is practical.
So that's it for today. I hope you liked it and don't hesitate to contact me if you've got any questions!