When you want to remove rocks, clods, or large chunks of vegetable matter from compost or soil it helps to have a portable shaker, similar to those used on archaeology digs. There are smaller handheld models and larger shakers. Each has its place. I built this shaker several years ago from salvaged wood, nailing everything together. I now use screws on projects whenever suitable. To build a light, portable, four-legged shaker you will need:
6 pc.-1" x 4" x 32"
2 pc.- 1" x 4" x 16"
2 pc.-1" x 2" x 19"
1 pc.-1" x 4" x 32" (ends to be cut for a diagonal brace)
2 pc.-2-1/2" x 1/4" hex bolt
4 pc.-1/4" hex nut
4 pc.-1/4" washer
8 pc.-2" x #8 screw
20 pc.-1-1/4 x #6 screws
20+/- pc.-3/4" poultry staples
1 pc.-16" x 20" galvanized 1/2" hardware cloth ( a good hardware store may cut just the amount you need instead of buying a roll)
Drill & bits
2 wrenches for 1/4" nuts
Screwdriver or drive bit for drill
Needle nose pliers
Step 1: Assembling the Screen
If you are going to shape the handles, this is the time to do it. Remove a 2" x 6" piece from one end of two of the 32" long pieces. These are the long horizontal pieces. Use the rasp to remove the sharp edges since this is where you will grip the sifter to shake it. Mine doesn't have this improvement but the photo shows where to remove the wood.
The top is just a box with the cross pieces set in from the ends of the long horizontal pieces. Measure in and mark 3-1/2" from the end opposite the shaped handles. Drill and countersink two holes on this line, each 1" from the edges of the board. Before installing the rear cross piece, make sure the hardware cloth screen is going to fit. Adjust the location as needed. Measure and mark another line 19-1/2" from the first line and holes back towards the handle end of the long horizontal pieces. Drill and countersink two more holes in both long horizontal pieces. Drill a 5/16" hole in each piece 1-3/4" from the square end of each piece, centered top to bottom. This is the pivot hole for the front set of legs.
Assemble the 16" cross pieces between the long pieces using 2" screws. It is a good idea to drill a pilot hole first, to prevent splitting.
Cut the hardware cloth to size. Make sure it overlaps the wood on all four sides and that there is enough room to staple it. Using the shaped handles as your guide, turn the assembly upside down and attach the hardware cloth using poultry staples. I find it easier to hold the staple with a needle nose pliers so I don't smash my fingers.
Step 2: Leg Assembly and Use
Drill pilot holes in the 2 pc.-1" x 2" x 19" (cross braces) so they can be screwed to the 3/4' side of the 32" legs. Attach a cross brace perpendicular to two legs using 1-1/4" screws about 3" from the bottom of each leg. Do the same for the other pair of legs.
Attach the rear (towards the operator) set of legs to the long horizontal pieces just ahead of the hand grips. Drill pilot holes and secure using four (4) 1-1/4" screws for each leg.
Position the front set of legs so the uprights are centered on the 5/16" holes. Mark the hole positions on the legs and drill using a 5/16" bit. Reposition the legs, align the holes, and loosely secure them using a bolt and two nuts. Use a washer on the bolt head side and on the nuts side. Don't tighten the nuts so the legs are tight. They must be able to move. Tighten the nuts against each other to prevent their falling off.
Align the remaining 1" x 4" x 32" piece diagonally on the front set of legs. Mark it for cutting, roughly 45o on each end. Drill pilot holes and secure the brace using 1-1/4" screws. Sign and date your sifter.
To use your sifter, take it to the job site and add a few shovels full of compost (not enough to fill the sifter). Lift the stationary legs off the ground and shake the sifter back and forth. The small pieces will pass through the screen and the larger pieces will stay in the sifter. An old dustpan is helpful in removing the big chunks. Aside the big ones to a bucket for later disposal.