How to Construct a Grease Trap
- 1). Measure the 55-gallon plastic barrel with a measuring tape and ensure it is at least 35 inches tall. This will allow for plenty of working room. Draw a line around the drum with the marker 6 inches from the top of the barrel. Remove the top of the drum with a hand saw, cutting along the drawn line. The top will be used later for accessible cleaning and maintenance.
- 2). Measure the diameter of the sink's outtake pipe on the sink where the grease trap will be placed. With the marker, draw a circle on each side of the barrel 6 inches down from the top of the barrel. Use a razor blade to cut out the circles on the sides of the barrel. These holes will house the plumbing pipe.
- 3). Measure the interior of the barrel and cut a plastic sheet to fit around its width and bottom. The sheet must be 6 inches longer than the height of the barrel since a piece was removed. The sheet must be cut where the intake and outtake holes on the barrel are located. Seal the sheet into place with epoxy sealant and use the razor blade to cut out two holes. Place epoxy around the holes so the plastic sheet can make a forming seal.
- 4). Place the barrel under or as close to the sink as possible. It may not be able to fit comfortably under a sink area, so near the sink will be fine. Remove the pipe from the sink waste line and reroute the pipe into the barrel intake hole, the side closest to the pipe. Insert a piece of plumbing pipe into the outtake slot on the barrel to drain into a soil line. Place epoxy sealant around each pipe to ensure a lasting hold. Insert an elbow joint on the end of the outtake pipe so it is inside the barrel. This will help discharge grease quicker so the barrel does not fill up. Place the barrel's top back on and empty the barrel.
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