Combines straw chopper and corn

The idea for a high volume crop like corn, is to use the corn head to pick the cobs off the plants, and only pass these through the combine. The cobs, which take longer than stalks to decay are then chopped to speed breakdown. The less volume you have going through the combine, the faster you can go and the less wear on your combine. If you wanted to feed the whole corn plant through the combine, you could use a straight cut head, but the volume would be so high you'd have to slow right down, and you'd take a lot more of the corn out the back with the high volume of residue. The usual way to chop corn stalk residue is to chop it with a rotary or flail mower with a pass after you've combined. Wide rotary mowers and high powered tractors are used for this in order to cover ground quickly. Claas Combines list an accessory for their corn heads called an underslung chopper. It's actually a flail mower attached under the corn head running the full width of the corn head. There wouldn't be enough room to mount a rotary mower there. While flail mowers do a better job than rotary mowers, they are a far higher maintenance item. In addition, they would use a lot of power in high corn residue situations. Maybe that's why the idea hasn't caught on all that well with farmers and other manufacturers.

thanks for the explanation, cookiejar. i had seen a direct cut doin corn about 30 years ago and it is a slow operation. i guess i should have explained more. in our area , grain corn is a 1 year in 5 crop - weather allowing the corn to mature. however , ear corn silage is a definite possibility. forage harvesters here allow a 2 row snapper head maybe 3 , to be used. we have started to build a giant ear corn snapper but don't want to process in the field. we are custom operaters and the farmers we'll harvest for have their own processors be it roller or recutter. we have taken a combine , removed the walkers, shoe, front pan and everything to do with the separation and cleaning. the cylinder, beater and concave are intact. i want to use the straw chopper to downsize the MOG , after the snapper head has snapped the stalk, and the cylinder busted the cob up, to be able to blow everything the snapper head took off, into an accompanying wagon or truck. the idea being to snap corn and preprocess it small enough to blow and do this whole operation with some speed. so the question again. is the straw chopper capable of doing this - handling what the snapper pulls off and sends thru the cylinderIJ thanks

WOW! My only definitive comment would be that this use of the combine would invalidate it's warranty. I really believe that your operation would be asking way too much of the stock chopper both from the volume going through it and of the capacity of the drive to transmit the power you would need to go at the speed you want, even after removing as many knives as you could from the chopper. Then you'd run the risk of busting up the combine body with all that action going on in the sheet metal rear. This approach would cost a lot of blood, sweat and tears. I've heard reports that even expensive self- propelled forage harvestors from JD don't stand up in heavy duty custom applications, and that the Class forage harvestors survive the best of the bunch. That may be the place to look.

thanks , cookiejar. MF warranty on this machine was over a looooooooooooooooooong time ago. new warranty applies now - "FarmerTom's warranty". have a good day.

Farmer Tom, Interesting reading about your ear corn harvester. You may already be aware of this concept, but in our part of the world we accomplish what you are talking about without major combine modifications. Generally refered to as "cob chop". Works with both rotary or convetional machines. Speed your cylynder_rotor up as fast as possible. ( I'm running a CIH Rotor at 1000-1200 RPMs) And tighten concave down all the way. This crushes cobs and forces all corn and most of cob through concave. We either pull seives altogether or replace the chaffer with a special seive built for the purpose which I will only attempt to describe if you care to know. Set fan back to 700 or so as to blow out some of the husks and light fodder. This leaves you with a product that almost runs out of the bin, so we modify the stock bin auger covers to allow material to flow better. Know of one operator who added a beater above augers to help unloading bin. Depending on conitions this gives you product with 75-95% of the cob, and an insigificant amount of fodder. Works well in corn 20-28% moisure. Farmers then run this through either roller mill ofr hammer mill. My apologies if you already know all this, be glad to answer any questions if you want to know more.