Hi! When i got this handy little devkit i my hands i immediately thought of a project that would be ideal for a web-enabled device: An automatic gardener! So i went and bought some little pumps on the internet that would later serve as core of this system. But days passed and ordered parts would not show up at my doorstep. So i decided instead on documenting at least some parts of my project. So in this blog post i will show you how to quickly develop a case for your Azure Sphere Devkit (and in extension your other electronics!), using CAD software such as Fusion 360 and any 3d printer.
This is NOT a comprehensive guide to making this from scratch, I only recommend using this blog for general guidelines what may aid you in prototyping process.
Little 5V pump from aliexpress.
Damn you chinese packages! (57 days and counting...)
What you need:
- A decent camera and stand for it (or in my case an Internet browser)
- A CAD software (Im using Fusion 360 with free education license, buy you can use other free software)
- A 3D printer (I'm using an ancient Mendel90 machine, it is old and prone to failures during printing but it prints decent enough)
And of course some basic understanding of CAD prototyping and 3d printing.
There are many ways to prototype cases for your devices. Orthodox way is that you carefully plot all critical dimensions onto paper, and double check everything with your measuring tools. Or you can utilize my method that produce results faster and it's also easy to use.
1. Take a photo of your Azure sphere devkit laying on a smooth level surface. You should end with a top-down view of a PCB. You need to do this as precisely as possible so i recommend using some sort of mount to steady your camera. I didn't have to do this because i found suitable photo right on this very site! I'll attach it for you so you can start faster.
Top down view of an Azure Sphere Devkit (full photo in attachments)
Only one dimension needed!
2. Open your CAD program of choice and import photo of your device. In Fusion 360 this can be done by clicking Insert > Canvas.
Now its time to calibrate your canvas. Click on your imported image nad select "Calibrate" , click on two points on your image and enter real-live measurement between those points. Volia! Now you can sketch on your photo and lines that you make should be 1:1 in scale to real life. If that is not the case you should retake your photo/use different points to calibrate.
3. Now all you need to do is to trust your design skills and artistic sense. My tip: first trace overall dimensions of device, including any ports and bits that may exceed overall "frame". Than use an command "Offset" to create walls of your case.
4. Now is time to extrude your creation. My design includes snap-on lid and internal standoffs. I also uploaded version without standoffs in case your 3d printer fails to print this (witch sadly was the problem in my case). For lid just use sketch that you developed earlier and extrude only parts that would make the lid (i decided to include cable hole and e14 logo that i found svg file on the internet)
5. Now is time to save your creation to STL file by right clicking it and selecting "Save to STL". Now we are ready to slice it in your slicing software of choice and begin printing!
For me the printing process took most of the time. Partly because of my old ancient... piece of fine technology that is my printer, but also because my way of prototyping is based largely on trial and error. So i really recommend this only if you have spare time and you own a 3d printer yourself. If you need to have someone to print it for you i recomment taking your time with measuring and drawing to avoid unnecessary costs.
Printing in progress
Done! A little small for a snug fit... (notice layer shift at the bottom due to low tension on X axis)
I've attached my STL and Fusion 360 project files in case you want to analyse what I have done, or just want to print things.
My tips when printing cases:
- Print the bottom (box) part with 101%-103% scale to compensate for material shrinkage and printer/your hand inaccuracies. Printing at an original scale may lead to your PCB not fitting at all.
- You may leave the lid portion of case as is so you would have a better time snapping it on rest of your case.
- Recommended valuses for my stl are: 20% infil, no supports and 0.2-0.3 layer height.
- Print "Body_standoffs" file only when you are confident in your printer, standoffs may end up too big/deformed if you have big nozzle diameters/extrusion multipliers.
103% scale, no standoffs. Fits perfectly!
With lid attached. Printed with PET-G filament (notice that due to overextrusion on my side element14 logo printed incorrectly)
I would like to thank everyone involved in this challenge for support and funding of those devkits. I know its not much, but i hope that this little project that i created may aid future makers in their endeavours with electronics. It's a shame that i cloud not finish my original project but i hope for future contest like these in the future.
... and sorry for my non-native English.