I’m fascinated by sous vide cooking, in which foods vacuum-sealed in plastic are immersed in a precisely temperature controlled hot water bath to achieve optimal doneness.

But most sous vide (soo-veed) cooking machines are commercial models that cost north of $2,000, and the first “home” version, the countertop SousVide Supreme, is priced in the neighborhood of $450 (not including vacuum sealer), which is still a steep investment for something that essentially keeps water warm. I decided to build a better device on the cheap.

Behold, the $75 DIY Sous Vide Heating Immersion Circulator! By scrapping together parts from eBay and Amazon, I created a portable device that heats and circulates water while maintaining a temperature accurate within 0.1°C. And unlike the SousVide Supreme, it mounts easily onto larger containers, up to about 15 gallons, for greater cooking capacity. The water is heated by three small immersion heaters and circulated by an aquarium pump to keep the temperature uniform. An industrial process temperature module controls the heaters, and an eye bolt lets you clamp the entire apparatus to the rim of a plastic tub or other container. To cook sous vide, you also need a vacuum sealer, which this project does not include. I bought a good one new for about $112.

This project first appeared in MAKE magazine, Volume 25. Subscribe today!