How to Build a Soybean Oil Press

Soybeans are a major cash crop in North America. Aside from being processed into food products or animal feed, they also yield oil. This oil can be used as a cooking oil, or burned as fuel in a biodiesel engine. Extracting this oil from the beans requires a press. Although soybeans are only 20-percent oil, and thus less energy-dense than sunflower oilseeds (which are up to 70-percent oil), a homemade seed-oil press will be able to turn them quickly into usable oil. You will need some basic welding skills to build a soybean oil press.

• 1

  Cut 1.75-inch metal tubing into two 24.5-inch pieces and one 6.5-inch piece. A carbide saw blade is essential to cut metal; these are available for whatever type of powered or unpowered saw you use to cut the tubing.

• 2

  Cut a 5.5-inch piece of flat steel bar and two 8-inch pieces of angle iron. The bar will serve as the top crossbar in your frame while the angle irons will join the frame to a wooden base.

• 3

  Stand all three tubes on their ends, with the long tubes 5.5 inches apart. Place the short tube in between them and use an arc welder to weld the steel crossbar at their top ends, and the angle iron pieces on both sides of their bottom ends. This will make a rectangular metal frame with the short pipe in the middle of one short side.

• 4

  File or grind any rough edges from your frame, then paint it. The paint will dampen down any shavings. Once painted, it can be attached to a wooden base by passing screws through the holes in the angle iron piece.

• 5

  Make the press canister by welding a circular piece cut from your plate steel onto one end of a wide steel tube. Drill holes through the outside of the canister and file down any rough edges.

• 6

  Form the press piston by cutting another circle of plate steel just small enough to fit inside the press canister. On one side of the disk, weld a short length of pipe with a diameter big enough to fit snugly over the end of the short pipe in the press's frame.

• 7

  Chop off the bottom third of a round plastic jug and cut a hole in the center of it big enough for the middle pipe in your frame. This will collect the oil as it drips from the press canister.

• 8

  Slide the plastic collection tray over top of the small pipe, then cap the pipe with the piston disk and pile soybeans on top of it. Set the cylinder snugly down onto the pile of soybeans.

• 9

  Slide a 3-ton jack between the frame crossbar and the press canister and pump the jack using the attached handle. As the jack extends, it will press the canister down onto the soybeans. The oil squeezed out will drip through the holes in the canister into the collection tray.