Belgian Waffle Maker Gets a Reflow Oven Makeover

Belgium's national dish happens to be fries (French fries), rather than their delicious waffles known worldwide. Besides making waffles, a waffle iron can be repurposed as another tool, one that can reflow solder PCBs. Engineers and makers have been utilizing convection ovens, clothes irons, and Easy-Bake ovens for reflow soldering for some time now as a way to repurpose old tech and save a ton of money.

Engineer Vince decided he needed a reflow oven, even though he doesn't produce many PCBs, but he needed it to be small, portable, and dirt cheap. Not wanting to shell out his hard-earned money, he went with the next best thing — a waffle iron. "The toaster in question is a 'Croq'Gaufres Express' by Moulinex. It has removable hotplates and is limited to 700 Watt, which is not much, but I thought it was worth a try," states Vince in his project blog. "I quickly put together an Arduino with a MAX6675 and K-type thermocouple to monitor the temperature in different conditions, but it was clear that with the hotplates, its inertia was too high, taking around 5 minutes to reach 150°C while most reflow profiles require around 1 or 2 minutes for that ramp."

After some trial and error, Vince removed the hotplates and replaced them with copper, wrapping them around the iron's heating element, which provides even heat along the top of a PCB and a reasonable warmup time. He also designed a custom controller for the ReflowWaffle using a Sonoff Wi-Fi smart switch, a MAX31855 breakout board, and a K-type thermocouple, which get the job done without being overly complicated.

Vince has uploaded a detailed walkthrough of his ReflowWaffle on his blog for those interested in recreating his build.