How do I do this? I need to calibrate a pull behind sprayer so I put the correct amount of - whatever I am spraying - on my fields. NOTHING I own to pull it has a speedometer. Can’t pull it with my truck.
What I did (and I only had to do it once), was fill the tank with water and drive the tractor over (marked) acreage until the tank was empty. We found that the tank sprayed 2 acres. Do you know your acreage? Fill your sprayer with water and then spray it. Spray a measured acre or spray the whole thing --regardless, you’ll then know the amount of liquid you need to cover what you want to.
My tractor doesn’t have a speedometer either so I measure out a set distance in a straight line, say 100 feet of level ground, and then time how long it takes to drive that distance at a set RPM. (Speed will vary a bit by RPM as you go up and down hill but it should stay close enough unless your fields are super hilly.) Then calculate speed in ft/sec = distance in feet / time in seconds. If you need mph you multiply the speed in ft/sec by 15/22. Then when you do the spraying, try to keep it at that RPM. That’s the best system I’ve managed to come up with.
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There are several apps you can get for hour smart phone that will give you gps based speed estimates. I’ve got one but my phone is upstairs. Go to either the Apple or Android market place and you’ll find something.
To figure out the flow rate in you sprayer put in 5 gal. of water, turn it one, and time it to empty with a stopwatch. If you don’t have one you can download one of them, too!
You now have all you need to calculate applications.
If you don’t have one, go on line and search for the manual for your spray rig. I’ll bet it has some tables in it to help you figure out what you need to do.
Good luck!
G.
Thanks. I’ll try the first method. Pretty sure I can get acerage from somewhere. The manual does not have charts. My Gator does not have rpm gauge.
