View Full Version : Spraying PSI & GPM question?

Bunton Guy
07-03-2003, 09:16 PM
What PSI are you guys spraying at? What gun are you using and what pattern are you spraying at? IS there a specific walking pattern that you use? I keep tripping over my hose...do you guys hold a part of the hose as you walk? Do you walk forwards when spraying or work your way sideways so you dont get caught in the ' mist ' of the spray gun?

Bunton Guy
07-03-2003, 09:18 PM
That picture above is spraying at 35-38 PSI.

Bunton Guy
07-03-2003, 09:19 PM
JD-9 Gun above...pretty straight forward spray...does seem to shoot alot of mist at me if I walk to quick.

Bunton Guy
07-03-2003, 09:22 PM
Another angle of the spray pattern. Im not sure if its right...but its what my tech set me up with....I havent yet got the ' walk ' down yet I kinda look goofy tripping over my hose all the time. I will be watching closely to see how other spraying co's are doing it. I wear rubber boots (wal-marts almost up to the knee) and rubber gloves (the type you wash dishes with) is that enough?

07-03-2003, 09:25 PM
Long Sleeves and Pants.

Bunton Guy
07-03-2003, 09:27 PM
I supose as soon as I learn the ropes I will be getting the chemlawn gun.

07-03-2003, 09:42 PM
Are you fogging for mosquito's???

My guy sprays the consistancy of what would come out of your mothers old watering can. Nice solid streams, about 20 individual streams.

I never seen any lawn spraying co. using a gun that puts out like yours!

Bunton Guy
07-03-2003, 09:44 PM
Thats because its the wrong gun LOL ! I need to get a chemlawn gun at Lesco come Monday.

Turf Medic
07-03-2003, 09:44 PM
Originally posted by Bunton Guy
I wear rubber boots (wal-marts almost up to the knee) and rubber gloves (the type you wash dishes with) is that enough?

No, at least in Nebraska those gloves and boots could potentially get you a violation. You must have protective equipment that is rated for the pesticides that you are using. I purchase my gloves and boots from gemplers. Both are made with a product called nitrile. http://www.gemplers.com You should check with your core test information to see exactly what protective gear you are required to have. This information can also be found on the labeling of the pesticide.

Bunton Guy
07-04-2003, 07:45 AM
I got the gloves at AM Leanard.

07-04-2003, 07:49 AM
I've used that gun, it's adjustable for light/heavy patterns. You can also get different tips and extentions for it. Maybe it's the pressure. I used a 12v shurflo pump and it worked just fine. I know when I pump my handheld B&G up around 40-60 pounds, I get more mist than I want. Try lowering the pressure, you may get better results.

07-04-2003, 09:14 AM
TLS has it right. When I'm spraying, my regulator meter hardly looks like the needle has moved off the '0'! The picture you have posted shows the dial 'way' up there! I'd blowout my diaphrams with that kind of pressure!..


Turf Medic
07-04-2003, 10:47 AM
There are a few people around here that use that gun without any problems. Try turning down your pressure to less than 10 psi, that is with the gun open. Then do a bucket test we spray at 2 gal per minute, you can adjust this very little by using pressure, you need to adjust the gal per minute primarily with the spray tip. I'm not sure if that gun is adjustable or if you have to replace the tip. I think that gun can also be used for deep root feeding and tree spraying, with the proper attachments

07-04-2003, 11:48 AM
I use a JD-9 for tree spraying and shrub spraying i.e. dormant oil applications. For lawn applications, I use a chemlawn gun.


07-04-2003, 12:48 PM
That gun is for spraying trees and shrubs, not lawns!! Once you get the right gun set you tank to 50-60 PSI with the yellow tip on, make sure you have water in the tank and then time how long it takes to fill a gallon jug, should be 30 seconds. Adjust the PSI accordingly until you are pumping 1 gallon in 30 sec (2 GPM). Most mixtures require 2 gallon per k, so it should take you 1 minute to spray 1k.

Turf Medic
07-04-2003, 01:12 PM
Bunton Guy PM me if you are interested in selling the jd-9 gun. No sense leaving it laying around, if you are going to replace it with the Lesco gun.

The Lawn Crew
07-05-2003, 03:04 AM
Use a flood nozzle that goes on a JD-9. Can calibrate to use either a 3gpm or 4gpm head. Pllace water in the tank and shoot the gun into a bucket and keep a watch on it. 15 seconds=1 gallon (using 4gpm head). Adjust pressure up or down so you are spraying 4gpm.

Next: Go to an empty parking lot and measure the width of your spraying motion that is comfortable and consistent; e.g 5 feet.

Measure out 1000 ft2. If you are spraying a 5' width, than a 100' section will tell you how much you are applying to 500ft2. Multiply by 2 to calculate 1000ft2. You can chalk it out with two lines 5' apart and 100' long.

If you're applying 4gpm (as calibrated into the bucket), then you should be using 2gallons to cover a 5' x 100' section.

A company GPM, I think, makes a flowmeter that attaches right before the gun so you can easily see how much liquid you've sprayed in the 500ft2.

Now it's a matter of adjusting your walking speed to apply exactly 2gallons/500ft2 which equals 4gallons/1000ft2.

Now when a label directs, say Super Trimec, 3/4 fl oz/1000ft2 you know to add 3/4 fl oz for every 4 gallons of tank water, because you are applying 4 gallons of liquid/1000ft2.

Hope this helps!

07-07-2003, 11:57 AM
The JD-9 was originally designed to blast barnacles off ships in dry-dock and was quickly adapted to use for Tree/Shrub apps. With the adjustable nozzle, I doubt very much you can hope to get a consistent spray pattern or coverage on turf. I know you have been told but a good turf gun like the old Chemlawn gun (Lesco bought the patent) would be your best bet. Nozzle sizes start at 1.0 and run through 4.5 GPM. Once you have the proper tip for the volume of material you are after bucket checks with a watch are pretty easy. You can even adapt the gun with a kit available from Westheffer to do "spot treatment." Droplet size is important for best control so I wouldn't recommend a nozzle higher than 3.0 gpm unless the product label calls for a higher total volume of material /acre

07-07-2003, 12:06 PM
One other thing, using the JD-9 may be tough to get the proper amount on the turf without fogging or misting. This opens up a whole new can of worms in regards to drift and possible damage to desirable plant material when using weed controls. A blanket treatment should be more a "drench" and not a spray. You will have to walk straight through your spray pattern but that is what PPE is for. I've been treating this way for over 22 yrs and never had a problem...but then again I read the labels front to back.