Tumblers allow you to quickly, easily, more often turn your compost pile without repetitive lifting. The frequent turning of the unit leads to better aeration. Air helps the bacteria breaking down the materials to do their work faster (than in a static pile). When more material is exposed to air, the bacteria grow quickly, supplied with additional food. The tumbling action breaks apart clumps that are normally malodorous and incompletely composted.
Piles should be turned every two to four weeks, but most are turned only every four to five weeks, if ever. Compost can be ready in three months or less with frequent turning, although the University of Illinois Extension Service recommends that you stop turning during colder months to prevent loss of valuable heat, potentially slowing the breakdown process.
Clean a 50-gallon drum or a metal garbage can. The container should not have previously been used to store any materials hazardous to humans or your garden soil (toxic chemicals, residual oil).
Drill holes around and along the sides. Use a half-inch drill bit. The holes may be randomly placed or applied in a pattern. Add holes 4 to 6 inches apart in rows approximately every 4 to 6 inches.
Secure the lid. Metal drums often come with a locking lid system. If you choose a trash can system with a removable lid, you may have to use less material per batch. Hold the lid in place using a length of rope or chain. Pass the rope through the handle of the lid and around the bottom of the can repeatedly (at least twice), and then knot the rope tightly (or lock the chain).
Create guide cuts for the rope/chain if you are using a rounded metal can and either tends to slip. Invert the can and use a pair of bolt cutters to snip notches into the rim at the base of the can. Cut one pair of notches (roughly opposite each other) for each wrap of rope. These will act as channels to keep the rope from sliding up over the rounded edge of the can.
Add material for composting a few pounds at a time so that you can test your ability to manipulate the unit. Turn the unit by simply tipping the drum on its side and rolling it. Leave it in that position (be sure to prevent it from rolling away by supporting the side with a chock block) or return it to an upright position. Roll the unit to the area where you want to spread the compost, once the contents are ready. Open the lid and rake out the contents.