Build Your Own Large Capacity Compost Drum for Less than a Hundred Dollars
While there are many compost drums on the market and many plans for home built ones; this one is a little different. I designed this compost system to easily transfer the finished compost into a garden cart. This system has few parts and all are easily obtained if you don't already have them on-hand. The system includes a barrel and the platform on which it rides. Here is a materials list.
One plastic 50 gallon barrel. I located three on Craigslist and paid for all three, so . Four three inch rigid-caster wheels. Harbor Freight has them for each, so for these. Treated wood, although I used 2X6's, treated deck wood would work just as well,. Paint for the barrel, .25. Paint for the platform,.50. Lag bolts and washers to mount the rigid casters .80. Two 2" PVC vent pipes cut from a ten foot length of pipe, . Four NIBCO 1 1/2 In. PVC DWV Trap Adapter Spigot x Slip Joints,. Window hardware: 8"continuous hinge and three cabinet latches, . The total is .55. Of course any of these materials you happen to have on hand will decrease your cost:
You will want the barrel to be black in order to absorb heat. I used Krylon's Fusion because the barrel I located was blue plastic. I figured Fusion would adhere better, but, truth to tell, any enamel should work as well. I used brush-on green enamel for the platform, but since I used treated wood, even this step is not essential. If you can find a black barrel and don't mind an unpainted platform, knock off .75.
The dimensions of the platform will depend upon the barrel you find. The barrel should ride on inverted casters mounted on the top of the platform. Position the casters so that the barrel will not jump off in either direction. If your barrel has beads where the top and bottom were attached, locate the casters just inside those beads. If your barrel is like mine, with a bead at the top and a taper at the bottom, the wheels should hit the barrel where it tapers at the bottom and just inside the bead at the top. Since there was no bead at the bottom, I attached a board between the wheels at what was the top of the barrel to keep the barrel from jumping off in that direction. The garden cart you plan to use will govern the height of your compost barrel's platform.
You will want an access port for putting in your raw materials and for dumping your finished compost into your garden cart. I cut a window in the side of the barrel between its two ribs. I pop-riveted a continuous hinge and three cabinet latches to the piece that I had cut out of the barrel.
All good composters have a good vent system. You want air to circulate throughout your compost, but you don't want to let bugs in with the air. My barrel already had two holes in the top so I cut two 2" holes in the bottom that lined up with them. I then cut two lengths of 2" PVC pipe long enough to stick out of the barrel about 1 ½" top and bottom and then drilled several ½" holes in both pipes along the length that will be inside the barrel. After inserting the vent pipes in the barrel I then glued the Nibco fittings on the ends. This fitting has a screw-on cap that would have been used as a pressure fitting for a slip joint. Just unscrewed these caps and cut out a piece of screen cloth to fit inside them. Screw the caps on to the pipes then use some putty to fill any gaps between the pipes and the holes you had cut in the barrel. Find a good place set up, place the barrel on its platform and start throwing in those table scraps and grass clippings. It would be a good idea to keep the compost level inside the barrel just below the vent pipes so that rotating the barrel won't be too much of a task.
