A GPS-controlled variable-rate applicator built by Kelly McNichols delivers fertilizer from outlets spaced across a boom—an advantage over a spinner in windy conditions.
Farmer-built air boom reduces dry fertilizer drift
Around Burr Oak, Kan., Kelly McNichols is known for the creations that come out of his farm shop. So when his neighbor Joe Herz wanted a GPS-controlled air-delivery fertilizer applicator, he knew who to turn to.
The applicator McNichols built won the Technology category of Farm Journal’s "I Built the Best" contest.
"Delivering fertilizer with outlets spaced across a boom lends itself to GPS control and variable-rate application," McNichols notes. "It’s well-suited for areas like ours. We have a lot of Farmer-built air boom reduces dry fertilizer drift By Darrell Smith Rugged Applicator wind, which can distort the pattern of a spinner applicator."
McNichols had a Gandy Orbit-Air delivery unit in his shed, waiting for a new mission. He had used it on a no-till air seeder that he built a few years ago.
Building Herz’s applicator involved constructing a caddy for the hopper and air delivery unit, fabricating a boom and setting up GPS controls.
For the center of the caddy’s triangular frame, McNichols used 4"×6", 3⁄8"-wall steel tubing. For the outer framework, he used 3"×3", ¼"-wall tubing. He set the frame on the axle and wheels from a Massey Ferguson 750 combine, confident they would be strong enough to support the weight of the hopper. For insurance, he reinforced the connection of the axle to the main frame with gussets.
McNichols framed the 48' boom’s center section with 4"×4", 1⁄4"-wall steel tubing. The lower bar of the wings is made from 3"×3", 3⁄16"-wall tubing. The upper diagonal framework is made from 1"×2", 11-gauge tubing. He mounted 24 fertilizer tubes on 24" spacings.
The boom is anchored onto the quick attach frame by two 1" bolts.
"It goes on or off in five minutes,"
Fertilizer leaves the applicator’s manifold through flex hose, which carries it to metal elbows on the center section of the boom. McNichols fabricated the elbows from 1" conduit. At the hinge point of the boom, the conduit is connected to flex hose, letting the boom pivot for folding. Past the hinge, the fertilizer completes its journey down the length of the boom through more 1" conduit.
McNichols used 1" conduit for the elbows because it’s readily available. "Elbows are the first thing to wear out, so I wanted to be able to replace them easily," he says.
To connect the elbows to the boom frame, McNichols used clamps made from plastic bearings and U-bolts from the pickup reel of a combine. "I staggered the clamps to fit them all in," he says. "The spacing had to be the same as on the original quick-attach manifolds on the other end, so the hose wouldn’t pull when the boom is raised or lowered."
- December 2012