Help In Calibrating Boom/Selecting Nozzle

Discussion in 'Pesticide & Herbicide Application' started by ed2hess, Feb 23, 2013.

  1. ed2hess

    ed2hess LawnSite Fanatic
    Messages: 14,567

    I want to understand spraying calibration for WBGone using my 5ft. spray boom. I need help in selecting nozzle type and how much WB gon in
    my 33gal tank for that nozzle.

    Speed = 3.78mph... made several 500 ft runs
    WBGone = 2 oz. per 500 sq. ft. so 1.36 gal/acre is cal correct
    Boom size = 5 ft with 3 nozzles so 20spacing
    Nozzles grey= running out 1 gal/min for the 3 nozzles
    Pump rated 30psi-50psi --no pressure gage
    Size of tank = 33 gal

    I need to get more area with the 33 gal tank Be patient with me I am trying to study ino on this site but I am hung up somewhere.

    CHARLES CUE LawnSite Silver Member
    Messages: 2,451

    Here is a calculator that you can use from tee jet this will help you out
    Why don't you use a 3way herbicide most likly cheaper. You can check your self

    Also tee jet has a chart for there tip to decide what size tip you need i would look at AI the tips

    Charles Cue
    Last edited: Feb 24, 2013

    CHARLES CUE LawnSite Silver Member
    Messages: 2,451

  4. Ric

    Ric LawnSite Fanatic
    Messages: 11,969


    Calibration is easier than you think. Most people want to over think calibration. Yes I taught Materials Calculation and Calibration at Edison College. The frustrating thing was Calibration is 6th grade math and my college students couldn't perform the simple calculations. only 78% finish High School and of the 78%, only 50% can pass a GED Test.

    1# Each sprayer is different so first find out what out put your sprayer is doing. Make it easy on your self and measure a 200 ft run on a street with no traffic. At 5 ft wide and 200ft long you are measuring a 1000 sq ft. With a clean tank water only, mark the water height of your tank on level ground. Now make a spray run up and down the street and measure how much water you used by refilling with a measuring cup in the same level spot. BTW you can also see the distribution of your spray on the street.

    2# now you know your carrier rate per thousand and can mix chemicals accordingly. Let's say you averaged 96 oz of carrier per 1000 sq ft. BTW that would mean 33 gal an acre.

    WBgone rate is 2 oz per 500 sq ft or 4 oz per thousand. In my above example I said your sprayer was applying 96 oz per thousand which means your 33 tank would do ONE acre or 44 thousand sq ft. 44 thousand sq ft times 4 oz means you would put 176 oz or 1 gallon 1 quart and one pint of WBgone in the example tank. BTW don't forget the surfactant which in most are 0.25% or one quart per 100 gallons. Your 33 gallon tank would only need 10 oz of surfactant no matter what the out put. surfactant is calibrated by the volume of carrier(water) not the sq ft.

    Changing nozzles, use the Chart Charles Cue gave a link. But once you install the new nozzles start all over again making a run up & down the street to find your application rate per thousand.

  5. RigglePLC

    RigglePLC LawnSite Fanatic
    Messages: 13,800

    2 ounces per 500 sqft equals 4 ounces per thousand sqft. (That is 1.36 gals per acre).
    1 mph equals 88 ft per minute. (332 ft per minute).
    At 5 ft wide you are covering 1663 sqft per minute.
    At one gal per minute you have 33 minutes of spraying time.
    That would be 54,879 sqft per tank.
    54.879 times 4 ounces would be 219 ounces herbicide per tank. (That is 1.71 gallons).
    You are correct. In my opinion.
    However, you say the output is one gal per minute. I suspect this is read from a chart. In ral life, it never comes out even at 1 gallon per minute--that would make it too easy. Collect the output from the nozzles in three jars and combine to get the real output per minute. REcalculate.

    Now put the exact amount you need into the tank and spray--if it comes out even you are a better man than I am.

    Oh wait...Ric answered...I will have to read his answer first.
    Last edited: Feb 24, 2013
  6. Ric

    Ric LawnSite Fanatic
    Messages: 11,969


    I can't help but notice you like to over think very simple problems.

  7. ed2hess

    ed2hess LawnSite Fanatic
    Messages: 14,567

    All my runs were real on the street to get the results I posted

    1. I have made runs on weeds at 48oz in the 33 gal tank and with good kil
    So I should increase it by 3.6. Don't seem reasonable.

    2. I have grey nozzles I thougth the ISO color standards indicate that a grey nozzle should spray 0.6 gal/min. In reality they onlly sprayed .33gal/min for each nozzle?

    3. I want to get more acreage out of my 33 gal tank. If I change
    from grey nozzles(.6gal/min) to blue nozzles(0.3gal/min) I should
    double the acreage I cover?
  8. ed2hess

    ed2hess LawnSite Fanatic
    Messages: 14,567

  9. ArTurf

    ArTurf LawnSite Platinum Member
    Male, from Ark
    Messages: 4,471

    Do yourself a favor and put a gauge on your sprayer. You can learn to do all the math and thats good but just looking at the charts is easier.
  10. Ric

    Ric LawnSite Fanatic
    Messages: 11,969


    It is better to teach you how, than give you an answer you don't know how to get. On purpose I gave how to get the calibration but I did not give you the Calibration. Math is cool but practical application of measuring your actual out put per thousand is a more actuate method.

    Reducing the out put in half by using .3 gal nozzles might not give you double the area per tank load of .6 gal nozzles. Smaller nozzle will normally increase PSI and therefore put out more than half than the original nozzles.

    Remember the less carrier and more AI in the spray the more chance of mistakes and Burning the lawn.


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