If you have the right calculations and tools, calibrating your sprayer will take about 30 minutes. This is an easy process if you follow this step by step explanation. When I wanted to learn how to calibrate a sprayer, I decided to do some research to discover the process. I found it extremely difficult to find a basic explanation all on one page. For those of you in that situation, here is the best explained procedure to follow.
Tools You Will Need to Calibrate Your Sprayer:
Having the right tools with you before you start will save you a lot of time. The tools below are what I used when I ran through this simple process. There may be other tools you can use but these will work best.
4 Tools You Will Need:
- Jug marked with ounces (30 oz. or larger).
- Timer or stopwatch.
- Trundle wheel or a tape measure capable of measuring farther than 200 ft.
- Tooth brush (to clean any nozzles that are plugged).
The Complete Guide: Calibrating Your Sprayer
You can use this process to calibrate a UTV, ATV, tow behind or 3-point sprayer. This recommended process should be completed before boom spraying to ensure you are applying the right amount of spray chemical.
- Measure Nozzle Spacing - Measure the distance between each nozzle to determine the length of your travel distance.
Pro tip: The distance you need to travel changes based on your nozzle spacing.
Nozzle spacing = Distance to travel
16” = 255’
18” = 227’
20” = 204’
22” = 185’
24” = 170’
- Measure your Appropriate Travel Distance - Mark the distance with flags or between fence posts. Use a tape measure capable of measuring farther than 200 ft. or a trundle wheel.
Pro tip: A trundle wheel is a lot less hassel!
- Drive the Measured Distance (Timed) - Driving the sprayer at the intended spraying speed, time how long it takes to travel between the marked distance. Repeat this procedure and average the two measurements.
Pro tip: If you start the stop watch when your 'spray boom' passes the starter marker, make sure you stop the timer when the 'spray boom' crosses the end marker. This will keep it accurate.
- Set your Correct Spraying Pressure - With the sprayer parked and the pump running, set the ideal or intended pressure.
- Catch Output from Each Nozzle - Catch the output in a container (marked in ounces) for the same number of seconds it took to drive in step 3. Calculate the ‘average nozzle output’ by adding the individual outputs and then dividing by the number of nozzles tested.
- Clean the Nozzles (If Needed) - If any one nozzle’s output deviates from the manufacturers’ guidelines by more than 10%, the nozzle should be replaced or cleaned.
Pro tip: A toothbrush works wonders!
- Analyze Results - The ounces captured per nozzle equals the gallons-per-acre application rate. (eg: 16 ounces = 16 gallons-per-acre)
- Compare the Recommended Rate - If the gallons-per-acre rate is not within 5% of the intended rate, you will have to adjust the pressure you spray at or the speed you travel. You will have to repeat steps 3 - 7.
Related: Getting Your Sprayer Ready for Spring
I trust you found this calibration process a lot easier than a bunch of technical formulas on a page. I sure did. After researching this topic for some time, it is clear that the key thing to be careful about is your nozzle quality. If any of your nozzles get clogged up, the rate of the chemical being applied will change immediately. Keep those nozzles clean! If you have any questions, please comment below.