Multifunction Digital Thermometer

Step 4 Make The Case

To Prepare the case to hold the electronics, two things need to be done.

The first is to cut the holes for the LED display, variable resistor, two momentary pushbuttons and the power switch. I did this by first inserting the finished electronics into the tin. Next, keeping the tin in the exact same place, I used a laser as a guide to mark the edges of the part, then closing the lid, scratched along the laser line marking where to cut . I then drilled out any corners(such as the display hole). Finally, I used an exacto knife to cut along the lines. Don't worry about deforming the metal around the edges too much, it can easily be flattened later by putting a block of wood under one side, and hitting the edge lightly with a hammer.

The second thing that needs to be done is line the bottom with cardboard (preferably thin) to insulate the electronics from shorting on the metal bottom. This is easily done by pressing the Altoids case on the cardboard so it leaves a depression along the edges. Now just cut along the depression and insert it in the bottom of the tin (see the lase photo).