Keep corn heads and soybean platforms in tip-top shape for optimum performance
Bt cornstalks and green-stem soybeans have increased wear to corn heads and soybean platforms.
"Gathering chains (on corn heads) seem to be bearing the brunt of increased wear due to higher planting populations and tougher Bt cornstalks," says John Keller, AGCO Production Performance Manager. "The rollers on gathering chains should be cylindrical. If they’ve worn and are tapered, it’s time for new gathering chains."
Snapping rolls show wear in several areas. Most snapping rolls have a short "auger" section at the front of the roll. If that auger section has rounded or worn edges it may not evenly feed stalks into the rest of the roll.
Snapping rolls may also have rounded flute edges. Flute edges should be "crisp," not rounded. Tapered snapping rolls shouldn’t show daylight between the roll’s flutes more than halfway up the rolls, when viewed from above. Edges of straight-edge knife rolls should be parallel their full length.
Deck/stripper plates should have straight, square edges. Plates with rounded edges, or edges with half-moons worn where stalks are most frequently pulled between them, should be replaced.
On soybean platforms, the sickle is only one part of the entire cutterbar system challenged by modern, thick-stemmed modern soybeans.
Wear plates and hold-downs that control fore-aft and vertical movement of the sickle are oft- overlooked elements critical to optimum cutterbar performance.
"You don’t want much fore and after movement, or vertical movement, of the sickle as it moves through the guards," says Keller. "Grab a sickle section with a pair of pliers and try to move it front to rear, and up and down. If it moves front to back by more than 1/8 of an inch, or up and down at all, you need to inspect the wear plates and hold downs."
The thin, rectangular bar to which sickle sections attach—the knife support bar--can develop worn areas on its back or bottom side that allow excess freeplay. If hold-downs and wear plates cannot be adjusted to minimize fore/aft and vertical movement of the sickle, be suspicious of a worn knife support bar.
A well-adjusted cutterbar assembly will have minimal "slop" in its sickle movement. Clearances will be loose enough to allow free movement, but snug enough to generate some heat due to friction.
"If you run a cutterbar for a few minutes, then shut it off and lightly touch the guards and sickle sections, it’s okay if some of them are warm to the touch," says Jeff Gray, Claas (Lexion) Product Coordinator. "If a knife or guard is too hot to touch, or the metal is turning blue, it needs to be adjusted to give proper clearance."
Auger fingers on soybean platforms are critical for smooth feeding of crop into the combine feederhouse. Missing fingers can disrupt crop flow.
"You get optimum threshing and separation in the combine by feeding things smoothly from the platform into the feederhouse," says Kelly Kravig, CNH Product Marketing Manager . "If the cutterbar is cutting nicely, and the reel and auger are feeding it across the head smoothly, you can still get bunch feeding into the feederhouse if there are auger fingers missing."
Soybean platforms operate close to the ground and therefore perennial high-wear areas. Torn, worn or ragged poly skid plates on the bottoms of cutterbars increase drag and problems with "pushing" dirt and debris.
Clean off the topsides of skid shoes at least annually to maintain free movement of the skid shoes. Use high-pressure air, blown from front to rear, to remove all dirt and debris packed between the cutter bar and the front edge of skid shoes.
Cleaning skid shoes by blowing pressurized air from the rear toward the front packs debris at the "pinch point" where skid shoes attach to the back of the cutterbar, and inhibits free movement and "float" of the cutterbar.