Is Skookum the only professional?
This description is the proper way to calibrate a spreader. Three years ago I helped a friend try to calibrate his new Lesco spreader using the proper technique described by Skookum. He had streaking problems in the little use the previous year. After trying to properly set the distribution for half a day, he gave up and never used the Lesco again. This spreader put out an extremely heavy band of fertilizer just right of center. Coincidentally, a golf magazine reported the same results four months later. Trusting the seller is an easy way to go, but you never know if he's telling you straight until you test it yourself.
Even with this system of calibration, you cannot just say you are done. Each spreader must be calibrated at least once a year to correct for mechanical wear. Also, just because one model of one manufacturer has been calibrated, you cannot apply those settings to all like models. I have seen the settings for equal application of two units of the same model to be radically different, because of wear and manufacturing tolerances.
Another concern in calibration is changing flow rate in areas of varying humidity. Increased humidity causes a reduction in product flow rate, especially with fertilizers. When we are fertilizing, since calibration has been done in dry air of winter, we actually calibrate on every job. Previously measured area of jobsite and current weight applied are used to determine application rate at that moment. Have seen days where we have had to open up settings significantly to apply proper rate of fertilizer.
[Edited by GroundKprs on 02-02-2001 at 08:25 AM]
North central Indiana
<a href="http://members.aol.com/groundkprs/Entry/Educate.html">Learn About Turfgrass</a>