Converting a $20 Conventional Toaster Oven Into a Reflow Oven

Reflow ovens can make SMD soldering easier by cycling through a temperature profile that provides consistent temperature escalation. This causes the solder paste to melt under the surface mount components. Reflow ovens can be quite costly, especially for occasional use. Now, sunyecz06 has converted a $20 toaster oven into an automatic reflow oven.

This toaster oven contains a temperature control and timer control dial, which are turned by a stepper motor. A MAX31855 thermocouple is placed inside to monitor the temperature. An OLED screen displays real-time data, including the temperature. All of these components, concealed in the oven, are controlled through an Arduino 5V pro mini. Making this look cyberbpunk is a well placed Stepper motor, A4988 motor driver, and a slew of other components. The temperature control dial can rotate 300 degrees clockwise, which is capable of reaching the highest temperature. A limit switch is also used in order to prevent the stepper motor from rotating beyond 0 degrees and to keep it from damaging the temperature control dial.

Lead solder and lead-free solder incorporated profiles can be selected through a programmed menu, which can be accessed via two push buttons. If the wrong profile is chosen, the program restarts. Pressing both buttons at the same time resets the Arduino and turns the temperature dial down to zero. The buttons are ANDed together using transistor logic and the output is inverted, pulling the reset pin LOW on Arduino. Although the rest seems masterful you’ll find a bent nail, doubling as a trigger for the limit switch, secures the hex coupler on the stepper motor shaft.

The Arduino, thermocouple board, motor driver, and the end of the 12V DC cable have been soldered to a perfboard. The oven, which runs off 120V AC, doesn’t rely on additional circuitry and a rectifier to power everything up from a single plug. Instead, both the Arduino and its peripherals, which run off 12V DC, are powered separately (understandable). It’s a really wonderful build. It seems like a weekend project for sure. But, can it fit the eventual Xbox for soldering repair?