Last steps before moving to the shower

In my last few posts, I haphazardly put together the wiring to allow the unit to take a reading from the sensor and from the potentiometer and then compensate by turning the servo up or down. Now I need to actually stick the thing on the shower knob and test it out.

However, last night I thought of an easier way to set the temperature than using a potentiometer. Instead of messing with the pot as you would the shower knob in order to find the right temperature, just mess with the shower knob itself and then press a button on the unit to let it know you like this temperature. Later on, I'll include buttons to nudge the temperature up or down by a couple degrees if your tastes change. But for now, it'll be enough to just set the temperature yourself and tell the unit to keep it there. This will also allow me to avoid dealing with the issue of how hard it is to turn the shower on from the full off position, which requires a ton of torque. I thought I'd calculated it when I began this project, but either I wasn't accurate or my servos can't do what they claimed. Either way, I'll deal with it once I get the fundamentals of this thing working.

Ok, so the first step is to remove the pot, add a button, and program the unit to recognize a button-press as the signal to keep the temperature where it is.

The next step is to extend the wires to the sensor so it can get the temperature of the water. However, this will require a little waterproofing. Luckily, I think I can do this quick-n-dirty by putting a plastic bag over the sensor. Later on I'll embed it into a coupler with silicone glue, but for now I just want to take the dang temperature.

In this picture, the temperature sensor in the middle is highlighted. This is what I need to extend so it can reach the water.