Homebrew Build with a Beaglebone

To ensure I won’t electrocute myself when I spill my wort on the control panel, I used a NEMA 12 enclosure. These are rated for indoor use with resistance to water, dust, and rust. Perfect for the damp environment it will be in during boils.
I chose a 12″ x 10″ x 6″ sized enclosure. This is smaller than many other builds you will see online, but because I am not using the bulky mechanical switches, I saved a lot of space. Using the Beaglebone really simplified things.

I used a similar product to what most are using:
Rust-Oleum Hammered Burnished Spray Paint. As the name implies, it leaves a nice, irregular hammered finish.
There are a few different colors to choose from.

In order for the spray paint to adhere properly, you really need to sand off the enclosure’s pre existing paint and apply some type of primer. I did not do this and my paint comes off incredibly easy. I wouldn’t bother painting it again if I was not going to do some surface treatment beforehand.

My enclosure already had a removable panel, but it was not deep enough for the solid state relays. I would suggest using a dremel for this because if you use a hand saw like I did, it takes forever and looks bad (though it isn’t visible anyways once completed).

Sand down the sharp edges and get your heatsink ready. I used a 300mm x 120mm x 20mm sized heatsink I found on eBay. The size was absolutely perfect for my enclosure and has plenty of room for the relays to mount on the underside. To mount to the enclosure, apply a generous amount of JB Weld around the hole. You really can be generous here- you want a seal between the heatsink and the opening.

Before wiring, I tested my device tree overlay and wiring with a breadboard. I’ve covered this step in another post.

A lot of people reccomend using a hole punch for making the optimal holes for your connectors and indicators. I did not have any punches available to me, and could not justify their expense for a couple of holes so I went with a step bit. I went a mid-ranged priced step bit, the Neiko Titanium (the cheap ones will only last a couple of holes!).
The thickness of my NEMA enclosure was not that significant, so using the step bit really was not an issue. You will have a bit of filing to do afterwards, but if you take your time, you can have nice, clean holes in your enclosure using a step bit.

Neutrik is most known for producing A/V connectors for speakers and microphones. While looking for cheaper alternatives to the expensive mains power connectors, I discovered they also make connectors for mains power!
I found several advantages by using these: I saved a lot of money, the connectors are all locking, and I also saved a significant amount of space on my control panel because these connectors are about half the size of their typical counterparts.

Making sure both 120V lines remained separate was something I wanted to pay particular attention to. I’d suggest wiring up one side first, then the second.

Beaglebone mounted and powered on. Don’t forget to use standoffs when mounting. These are hollow plastic tubes that fit over a portion of your screws. This will prevent the shorting of your beaglebone that would occur if its rear contacts touched the metal mounting plate. I chose to use an old router power brick to power the beaglebone. It is large and clumsy, so you could potentially save some needed space by adding another external connector and using the supply externally, but I wanted to have everything enclosed.

Everything now wired up and functioning (BBB powered externally in photo). I have not completed my cable management yet. Notice the small sainsmart relays in the center. I am using these as switches for my pumps. The build quality is actually pretty good on these. Becuase I cut corners and I am using the cheap “eBay” pump,
I repurposed another power supply I found laying around. You shouldn’t have trouble finding one that is 12V- look for old modems, routers, cordless phone bases, etc. They are fairly ubiquitous. Most of these will not have difficulty powering the smaller pump, but still check the amperage.