Marion Calmer on Combine Sieve Settings - Harvest 2016

[@lukestrawwalker]

I always used the "book recommendations" as the STARTING POINT not the END POINT in adjusting the combine... Every adjustment through the system affects the ones afterwards, and some adjustments increase capacity and some reduce capacity. Speeding up the rotor or cylinder increases throughput and thus capacity, reducing rotor or cylinder speed reduces capacity. Opening up the concaves increases volume space for more throughput, increasing capacity, while closing the concaves up against the rotor or cylinder reduces capacity. Opening the chaffer and sieves allows more material to pass, closing them reduces capacity to pass material. Capacity= volume/mass of material passing through the combine in a given amount of time, which is basically a function of GROUND SPEED and CROP YIELD/HARVEST CONDITIONS, ie how much material is coming into the combine (standing crops cutting well reducing extraneous matter coming in, while weedy or lodged crops require harvesting more of the straw or stalks to get the grain and bringing more extraneous matter in with the crop that the combine must pass through and separate the grain from and clean out.) SO, basically I'd start at the FASTEST recommended rotor/cylinder speed for a given crop and combine, the WIDEST or LOWEST concave setting for the recommended crop in that combine, the WIDEST openings recommended for the crop on both the chaffer and sieve, and the MOST airflow recommended (cleaning fan speed). Give her a test run and stop, see what she's doing. If there's unthreshed grain left, your choices are 1) increase rotor/cylinder speed (increases capacity) or 2) decrease concave clearance (reduces capacity). If you're getting cracked grain, FIRST look at rotor/cylinder speed (slow it down, reducing capacity) or insufficient concave clearance (open it up the bars are bashing the grain so hard or in tight quarters, increasing capacity) OR also look at returns (excess grain riding over the sieve and ending up in the returns, which usually cracks the second time around through the cylinder from the extra impacts of the bars on the grain). Ground speed can be a factor-- if you're simply feeding TOO MUCH MATERIAL for the conditions and trying to ram all that material through the thresher in too short a period of time, there's "no room" for the grain to "get out of the way" of the rotor/cylinder bars and thus it gets impacted too hard too many times-- no "cushion" from the material, as it's packed in TOO TIGHT through the thresher and thus cracks grain and will PULL HARD on the machine. Slowing down to reduce the thickness of the mat of material going through the thresher, giving it "more time to work" and providing more cushion to the grain and more space for grain to fall through in the straw and stalks will produce a MUCH better sample with less cracks, broken kernels, and scuffed grain, and less overloading of the chaffers and sieves with material ground to a pulp in the thresher coming down from the separator (walkers or rotor separator section). On the chaffer and sieve, similarly opening it increases throughput and thus capacity, and closing it reduces capacity. You want the MOST open chaffer and sieve settings you can use and still get a clean sample in the tank. AIRFLOW is the primary cleaning force in the combine, so you want the MAXIMUM airflow you can get away with WITHOUT blowing grain out the back. Trying to reduce losses off the back of the cleaning shoe and trying to get a cleaner sample by closing the chaffer and sieves while reducing the airflow from the fan (fan speed or shutter spacing) is counterproductive... Oftentimes I've found that I can open the chaffer and sieve up WIDE OPEN and increase fan speed to MAXIMUM and STILL put a clean sample in the tank, and not be blowing grain out the back of the combine off the cleaning shoe... maybe a few small immature kernels that are light and small and thus contribute little to yield, but a some of those will remain in the heads unthreshed, which beats OVERTHRESHING and grinding everything to a pulp and overloading the combine and chaffer/sieve with material TRYING IN VAIN to get "every last kernel" of the crop... SO long as the GOOD grain is getting threshed out of the heads completely, don't worry about a few undersize tip kernels or immature stuff. IF grain is getting blown out the back over the shoe, then REDUCE the chaffer setting SLIGHTLY, or REDUCE airflow SLIGHTLY. Some of these adjustments are quite subtle-- small adjustments can make a HUGE difference. If the sample in the tank is dirty, increasing airflow or reducing the chaffer and sieve openings should correct it. Always start from the UPPER end of the adjustment range and work DOWN in opening size and airflow to maximize capacity throughput and cleaning, until a clean sample is in the tank and grain isn't being blown out the back. OF course, GROUND SPEED can have a huge impact-- the more material going through the thresher in a given amount of time, the tighter it is, and the more broken straw, chaff, broken cobs or pods, etc will end up raining down out of the separators (walker or rotor rear) onto the cleaning shoe, which can overload it. It's all a BALANCING ACT... trading ground speed/throughput capacity for complete threshing and separation and the best cleaning for the cleanest sample of undamaged grain in the tank in the minimum amount of time. All these factors basically are at cross-purposes and so you can't have the best of *everything*, so you settle for the "happy medium" where everything is adjusted the best you can to pass the most material in the least amount of time and STILL get as close to complete threshing as possible (not underthreshed with good kernels still on the cob/pods/heads, but not overthreshed and broken all to pieces tons of chaff, busted cobs, pods, etc clogging the chaffer and sieve, but perhaps a few low-quality unthreshed immature kernels left after threshing and separating), and the best quality sample in the tank without riding grain out the back due to too much air or too narrow a chaffer or sieve setting, and minimizing cracked or split or damaged grain from excess tailings returns and "overpacking" the thresher through too high a ground speed. Later! OL J R :)

[@CalmerCornHeads]

Well! Should we have you do a guest post on our site! Thanks so much for the thorough discussion!!!!

[@kalburiumstormbreath]

Wow!! Thank you so much! We just got a 9670 STS bullet rotor John Deere combine. I was noticing what looked like cracked corn getting shot out the back. This info really helps!

[@lukestrawwalker]

@@kalburiumstormbreath You're welcome... OL J R :)

[@bradchoq]

consider running the fan speed 100 rpm faster than recommended and opening the pre-cleaner 1/8-3/3/16 more than recommended. The fan speed will blow out stalks and leaves that could fall through the chaffer. having more clean corn fall through the pre-cleaner will give the chaffer more capacity. With those settings, your limiting capacity will be clean grain elevator capacity. I delivered a bin of food grade white corn. The core had 3.8% mechanical damage and the rest of the bin had zero. Of corse, with 63-65 lb test weight, higher fan speeds won't throw corn out the back as easy.

[@tbishop6726]

Does this work for small grain also ....?

[@dschefers9700]

Do you have any experience with Bison rotors? We have one in a 1480. Works great in any condition soybean harvest. Corn on the other hand is difficult. Tons of crushed cob. Rotors open and at 250 rpms. Also have you ever thought of putting a panel to under the back of the top sieve on red combines so clean grain in the back section doesn’t get recycled?

[@CalmerCornHeads]

No personal experience with the Bison rotors. Feel free to call Marion at [phone] if you have specific recommendations you think would help our viewers. Thanks!

[@MFFMinorFamilyFarms]

Good advice

[@westernstarlowmax599]

Any ideas for soft red wheat?

[@CalmerCornHeads]

Call Marion on his cell at [phone] and he'd be happy to walk you through his thought process on it!

[@tf7274]

Open concave and increase wheel speed. Let the cobs thresh each other. Corn should be combined at the highest speed without leaving kernels on a whole cob. With a JD9500 with a 893 in 160bu corn I can do 5-6 mph all day. Strip the cobs off the plant...dont pull them into the header. Saves a ton of fuel too.

[@ViciouslyFish]

What do you set your top sieve at doing it that way? I would like to try this on my Deere.

[@CalmerCornHeads]

When harvesting corn, Marion recommends closing the top sieve to remove broken cobs and achieve the desired appearance in the gran tank. Visit our combine settings page for full information on settings combines for corn or soybeans. calmercornheads.com/in-the-field/combine-settings

[@grubbs03]

You should start with concave position. The cob should remain whole and exit though the chopper