Tweaking the Constants

Patriot Sprayers

The difference between the seasoned veteran and the operator that is starting out is the seasoned veteran knows that each time he or she applies a product, they are in a sense, calibrating their unit.  If the veteran applicator is one half acre short on product they know it immediately and make a change to the constants, allowing the next application to be on target.

A quick review of the following topics may resolve any issues with target application:

• Are your acres coming up correctly in the total area applied? If not, your speed calibration number may need recalibration.
• Is your profile for boom constants correct for your current nozzle spacing? Boom constants must match your current nozzle spacing to hit target rates.
• Remember the basics, speed and pressure.   You should know your expected target spray pressure for the speed range you wish to run.  Your spray pressure should increase when your speed increases.  The Unit should hold constant volume per minute.

Titan Floaters, Flex-Air

A Flex-Air operator experiencing under application may find a build-up of product under the belt or the main gate. Your spreader constant is reflective of the exact measurement or the gate setting you’re running.  Do not change you’re spreader constant until insuring the gate opening is clean of debris and there is no build-up of product under the belts.  If you are utilizing Co-Ap bins, the gandy wheels (supplement rollers) should be inspected for excessive wear or damage. 

When a spreader is used for multiple products, the density and granule size should be considered when determining constants.  One constant does not apply to all products.  All products have a “shear factor”.  The “shear factor” is dictated by the opening depth of the gate, granular size and density of the product being applied.  The larger the granule size and lower the density, and smaller opening in the gate will create a greater “shear factor”. When heavy density products reach the gate opening there is typically less shear. Make sure your constants are accurate for the product you are applying.