Last year I made a sifter for sifting compost. It’s just some 2×4’s screwed together with a piece of 1/2″ hardware cloth stapled to one side. The rectangle is 35 x 27, with the two shorter sides of the rectangle extended so that it can sit on our dump trailer or gorilla wagon. This is just a little smaller than the gorilla wagon opening.
We grow potatoes in grow bags. I discovered that dumping the bags into the sifter and sifting the potatoes out of the soil worked pretty well, but was a lot of work. You could shake the sifter by the bars, or push the dirt around with your hands. Either way, it took a lot of energy to do by hand.
I happen to be a fan of the Discovery Channel show Gold Rush, and one day, while watching their shaker deck processing plants operate, it hit me: A potato shaker deck! I just had to make a frame/stand for the sifter to attach to, and it would attach with some compression springs. Then some type of shaker motor attached to it to cause it to shake, and the dirt should fall through, leaving the potatoes behind.
I wanted it big enough to be able to go over either the dump cart or the gorilla wagon. The long legs of the sifter are 4′ long, and this would be about right. So I decided to make the frame identical to the sifter. Legs attached to the outside made it big enough to fit either cart underneath.
I found some 6″ x 1 1/8″ compression springs at a local farm store. At the lathe, I turned some spools from some red oak blocks to fit inside the springs, to attach them to the frame and sifter.
These are the springs attached to the frame. The are not secured in any way, just a slip fit over the spools.
I attached another set of the spools to the bottom of the screen deck, and inserted them into the compression springs.
I found this 40W vibration motor on Amazon, and attached it to the side of the sifter.
It worked pretty well. Check out the video of it’s initial operation.
I thought that maybe changing the orientation of the motor might help its operation, and I was correct. I remounted it so that the axis was horizontal. It works much better in this orientation. Check out the video below.