"It's much more convenient to use than pull-type rock pickers because it's so maneuverable and gives me a great view in front," says Larry Recker, Oelwein, Iowa, who mounted the reel and teeth assembly off an Abco rock-picking unit on front of a New Idea 709 Uni Harvester.
The 3 1/2-ft. wide, hydraulic-powered rock picker mounts in place of the Uni Harvester's husking bed and corn head. Recker built a 1/4-in. thick steel frame to support the rock picker as well as a 12-ft. long, 3-ft. wide slatted conveyor that mounts on one side of the combine.
The picker flips rocks onto a wide steel pan. Once the pan is full Recker raises it and dumps the rocks into a big steel box positioned over the front end of the conveyor. Once the box is full he raises it and drops the rocks onto the conveyor.
"Every time I dump rocks out of the box, I move the conveyor just far enough back to make room for the next dump," says Recker. "I can dump rocks into the box 3 or 4 times before I have to empty the conveyor. I usually unload rocks from the conveyor into a loader bucket and then use the bucket to load them onto a wagon for disposal. The conveyor came off an old wagon that I pulled years ago behind a seed corn picker."
The Uni Harvester's hydrostatic drive system works well to operate the rock picker and conveyor, says Recker. "I use foot-operated pedals to control the hydrostatic drive and the throttle, which leaves both my hands free to operate the hydraulic valves that control the rock picker. I use 2 hydraulic cylinders to raise and lower the rock picker, and 2 cylinders to dump the pan. The conveyor is driven by a hydraulic motor.
"I built it in the mid 1990's and use it each spring on every acre of our ground," says Recker. "I already had the Uni Harvester, which I had used for many years to pick seed corn.
"The rock picker can handle rocks as big as 2 ft. in diameter. If I have to dig a bigger rock out of the ground, I can bolt a heavy duty spear onto the picker and use it to push the rock out of the ground. Then I remove the spear and use the rock picker to pick it up off the ground."