This is an instructable for how to build a simple compost screen out of redwood and hardware cloth that can be used to sift foreign objects out of your compost or potting soil. It takes about 15 minutes to assemble and can weather the elements outside.

Step 1: Materials

The compost screen is built from:

2"x2" redwood stock (I prefer to build with cedar for outdoor applications since it is more abundant than redwood, but not all places carry it in California)
hardware cloth (This is like chicken wire. You can get it in 1/4" or 1/2" mesh. I used the 1/2" mesh so it will sift quicker)
staples
screws

You will also need the following tools:

chop saw (I used a chop saw to cut my frame but you can also use a hand saw with a miter box)
drill with bit and driver
hammer
tape measure

Step 2: Cut the Wood

Use the chop saw or a miter box to cut four pieces of the redwood of equal lengths. I made my screen 22"x22" (It couldn't be much bigger since I started with an 8' long piece of wood). Make your cuts at 45 degrees so that all four pieces can fit together like a picture frame.

Step 3: Assemble the Wood Frame

Pre-drill the holes for one or two screws at each of the mitered joints and then screw the four pieces together to make a sturdy frame. Put some glue on the edges that are being joined for extra strength.

Step 4: Cut the Hardware Cloth

Using a wire cutter, or angle grinder if you don't want to cut each one, cut the hardware cloth to the length and width of your frame. Don't cut it so big that it extends beyond the edge of your frame, but don't cut it too short otherwise you wont be able to fasten it. The wood is about 2" thick so you have some leeway to work with. I cut my hardware cloth to about 21" square.

Step 5: Attach the Screen to the Frame

Using the staples and a hammer attach the hardwire cloth to the frame. I hammered 5 in staples per side to keep the hardware cloth nice and tight.

Step 6: Sift Some Compost

Sift the soil through the screen before you use it for potting plants. You will find all kinds of stuff that you might not want in your soil - rocks, root balls, foreign objects - maybe even gold!