If you are the kind of person who won’t use cheap Sonoff modules to control AC powered devices, we don’t blame you and you should probably stop reading now. However, if you don’t mind a little exposed AC wiring and you have a 3D printer, you might be interested in the second generation of [530 Project’s] in-wall light switch.
The 3D printed switch fits a standard box and uses the guts of a Sonoff controller. These work with all the popular ecosystems such as Alexa and Google Home. And they are cheap. Like, really cheap. If you already have a 3D printer, even counting the cost of the filament these are going to be a small fraction of the cost of a commercial switch. You can see a video about the device, below.
Of course, for the price you pay for a TP-Link or other WiFi switch, you get a store to return it to, certain assurances that it won’t burn your house down, and — you know — someone to sue if it does. Those are probably all good things, but on the other hand, there are plenty of these modules around and assuming you know what you are doing, there is no reason to think they are going to explode, cause sterility, or any other bad things.
This is the second version of the Sonoff switch and it uses the switch built into the Sonoff for the local activation. Even if you are afraid of the AC line current, you might find a use for the clever toggle actuator [530 Project] put in the design.
If it makes you feel better, you can see a factory tour — these aren’t coming out of someone’s garage. You’ve probably noticed that since these Sonoff devices have ESP8266s inside, they are highly hackable. In fact, he has some custom firmware he uses with the switch. Among other things, it lets you trigger a reset by holding down the switch.