1Step 1The starting point for this project was the SparkFun Hatermatic. I bought or already had the items on the Hatermatic wishlist (see links), and went to my local equivalent of Harbor Freight to get a 50 cal ammo box. The eponymous "Craig" works for a military contractor, so "green" was important.
Lay out the panel and hole cutouts for the printer, coin receptacle, switches, and if you want, power cord hole. I used a plastic grommet from my junk collection for the wallwart cords.
I found the ammo box to be an excellent project case and will be using more of them. The main thing about cutting out the panels and holes is to wear hearing protection. The jigsaw work was pretty loud.
I had two spare rubber feet in my junk collection that I screwed at the bottom of the ammo case opposite to hinge so the box would be reasonably level when stood up.
As mentioned, I added a second (toggle) switch wired to A1 on the Arduino mini pro. The toggle has a built-in LED, so I used the Arduino 5V rail to power it.
I found the Adafruit small mint tin perf board to be ideal to mount two DC barrel connectors and the Arduino pro mini. I mounted it to the ammo box using some 1/2 " standoffs.
The rest is straight forward and follows the SparkFun guide online and GitHub repo stuff.