Meet the Enclosure
It is a well-known fact that engineers work at their best when we have a set of realistic constraints. So without further ado meet constraint number one, the enclosure. I have thought long and hard about what type of enclosure would suite something that sat quietly on a desk somewhere controlling much of your home.
We all want nice looking enclosures for our smart things. If you take enclosures for smart speakers as an example most of the market is fascinated with rounded enclosures, (think Amazon Echo, Google Home). Now these are great when you have an industrial design team and access to fabrication facilities, but most of us cannot buy these types of enclosures so we must re-purpose something we can find locally or 3D print an enclosure. Since I do not have access to a 3D printer or could not be bothered to design a enclosure in CAD for now, we are sticking to finding something off the shelf.
Based on the above, here are my requirements for the enclosure:
- It should be easily obtained.
- It should be easy to work with. (prototyping requires allot of iteration)
- It should be easy to make yourself in case it cannot be bought.
- It should support the idea of slot in cards/upgradability.
- Did I mention I like cubes, yes a cube shape it will be!
- But most of all it should be cheap.
Using the above criteria, I stumbled onto these hobby craft MDF cubes pictured below. You should be able to find them anywhere and if not you can easily make them using a variety of ways. The ones I get are available in multiple sizes but 120x120x125mm seem so be the sweet spot. This allows for (given a wall thickness of 6mm +-) an inner diameter of 108x108x113mm.
For now, this inner diameter is perfect because it will give us space to mount a PCB at the back and with all the support installed, a nice 100x105mm slot in card size.