Start with the concave set between 18 and 25 mm. For corn, a good practice is to measure the average cob diameter and use that as a starting point. If you see many broken cobs, adjust the setting to a wider gap. If you have issues with unthreshed corn, tighten the clearance.
A simple procedure for setting your concave is to grab a few cobs that have been threshed through your machine and measure their diameter in millimeters. Then, enter that value into your machine as the concave setting. After calibration, it’s good practice to verify that the setting you entered matches the actual concave setting.
The vane setting on a machine ranges from turtle/slow to rabbit/fast. These settings adjust the flow of grain through the rotor. The “rabbit” setting allows for faster flow, while “turtle” slows it down. We typically run this in the middle setting, adjusting as needed for conditions such as very hard-to-thresh corn, where slowing the vanes is beneficial.
Upper Sieve/ Chaffer – This sieve/chaffer focuses on grain cleaning, separating residue and crop material. If you see a lot of residue in the grain tank, tighten the sieve. Conversely, if you have a clean sample and are losing grain, ensure the sieve isn’t closed too much.
If we observe a lot of light trash, such as leaves, in our grain sample, we will increase the fan speed. Conversely, if the fan speed is set too high, we risk throwing grain out the back of the combine, a common issue with soybeans and other light grains.
Find some very good information for your specific Case Machine on this website – https://caseihharvesting.com/
Download the John Deere connect mobile app to find baseline settings for your machine.
