You can still change those tips to AI tips. The brass flat fan tips drift badly. I remember when that was all that Teejet really made for booms. An AI tip draws air into the stream of liquid. Air in the liquid means that the tip sprays out air filled bubbles that fall to the ground quickly and burst when they hit surfaces. That air filled bubble behaves like the lead balloon. It goes straight down. If you are spraying something with a lot of surfactant in it, the spray comes out like foam. An AI tip is also 110, meaning that you can have the boom 18" off the ground at 20" spacings. I am not sure of what your ground speed is going to be, so it is hard to say how many GPA. On wide open areas, I have applied at 20 GPA with good results. I am not comfortable going lower because of drift potential and the need for spray coverage. 5-10 GPA means either small spray droplets from the tips or else large droplets landing far apart.
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