New Zealand Bin
Sir Albert Howard, considered the father of modern composting, suggested this design to an Auckland, New Zealand gardening club, remarking that having a second one next to it would be the best arrangement, allowing one to fill with materials while the other was "fermenting". It is a very simple but effective design. This bin will hold about 39 bushels of organic material.
[Line drawing - New Zealand Bin]
|2 x 4 x 8 foot pressure treated lumber
|1 x 6 x 12 foot boards
|6d galvanized common nails
|10d common nails
|2 x 4 x 4'
|2 x 4 x 3' 4"
|2 x 4 x 4' 3"
|1 x 6 x 4
|1 x 6 x 3' 10"
Hand or power saw
1. After cutting all the pieces, take the four 2x4 posts and fashion some kind of point on one end of each which will later be driven into the ground.
2. Lay two of the 4 foot pieces of 2x4's on a flat surface and nail 6 pieces of 1 x 6 x 4" flush with the outside edges of the 2x4's, working from the top of the posts down. You want to leave a space between each board so use a couple of scrap pieces of 3/4" thick material as gauges to separate the 2 x 6 boards as you nail them on to the 2x4 posts. You should end up with a side of the compost bin close to 3 foot tall, with 8 to 10 inches of 2x4 left for pounding into the ground.
3. Now you want to attach an inside piece of 2x4 to serve as the guide for holding the boards making up the front of the bin. Clamp a piece of 2 x 4 x 3'in 7/8ths of an inch from the front of the front post and nail in place through 3 of the side boards. This is now the complete right side panel. Make the left side panel the same way. Remember to put the 3' piece of 2 x 4 on the inside of the front post.
4. Set the 2 panels front edge down the proper distance apart for attaching the 6 pieces 1'x 6' x 4". Clamp or lightly nail one board to the posts to facilitate holding the sides in place as you nail the boards to the rear posts of each side panel. Leave the 3/4 inch space between each board as you did with the side panels.
5. The loose top bar sits on top of the bin and prevents the sides from spreading when the bin is filled with organic materials. Use the 4' 3" piece of 2 x 4 to make this device. Nail 2 scrap pieces of 2 x 4 to the ends of the gauge with 10d common nails, making sure that the distance between the two scrap pieces is about 4 feet.
6. Once the bin is constructed, it must be set down into the ground. Take two of the front panel pieces and partially nail them into the groove made by the two pieces of 2x4 in the front of the bin. Nail one panel at the bottom and one at the top of the bin to make it square and relatively stiff. Remember to leave the nail heads out 1/4" so they can be removed when the bin is seated. Set the bin on level ground, driving the pointed posts into the ground gradually with a blow or two at each corner successively. Remove the nails from the front boards.
7. The remaining 6 pieces of 1 x 6 x 3' 10" are the removable slats for the front of the bin. To provide ventilating space as on the other 3 sides drive a 6d nail into the lower edge of each board about 3" from each end. They will rest on the board below creating the space between the boards.