Nick Sayer created a toaster oven reflow soldering controller:



It seems like a right of passage for makers that progress to surface mount work: building your own oven (or other appliance) to do reflow soldering.

The design consists of a power board and a controller.

  • Each channel of the power switcher is a basic opto-isolated triac circuit
    • MOC-3020 opto-isolated driver triac
    • BTA-20 power triac.
  • Controller monitors oven temperature and controls the heating elements
  • Thermocouple measures the temperature of the oven interior
  • PID controller makes oven temperature arrive at a setpoint without overshoot, undershoot or instability.

The firmware is availble in this GitHub repo:


nsayer has shared the boards on OSH Park:

Controller & LCD backpack (ATtiny84)

i (18).png

This variant has an ATTiny84 and an AD8495 analog thermocouple amplifier. It’s cheaper than the model II controller, but the flash is full, so there’s no room for more features.
Order from OSH Park


Controller & LCD backpack (ATMega328)

i (19)

This variant uses an ATMega328P controller and a MAX31855 thermocouple amplifier. It’s more expensive than the model I controller, but there’s lots of room for more features in the flash, it has connections for 3 buttons instead of just 1 and an FTDI serial port

Order from OSH Park

Nick’s Tindie store offers the following kits:

  • power board
  • Model I controller (ATTiny84/AD8495)
  • Model II controller (ATMega328P/MAX31855 variant)



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