Finished my lawn roller applicator system

jimgerken · Jun 14, 2010

I built this over the weekend. Well, the roller was already built and I added the chemical applicator system to it. It is a rebuild of an older system I had, so I know the idea works, but needed to be condensed to a smaller size (had too big a tank before and so was tippy on sidehills).
In use, the main roller tank (65 gallons) is filled to provide stability and do some good smoothing of the lawn. And the 15 gallon tank is filled with water and 5 or 6 oz of 2-4D 40% Amine-based product. The pump puts a continuous film of the weedkiller on the roller drum, and driving around presses the herbicide solution onto the lawn weeds to kill them. There is also a hand wand and 22 feet of hose for corners and details I cannot roll on.
The roll-on method does not ever atomize the spray so makes for less possibilty of any chemical drift. I was taught of this method by a good friend of mine whose dad had done it years ago (THANKS Dano !!!).

CharlieS · Jun 14, 2010

Interesting concept. With a conventional sprayer ground speed, nozzle size and system pressure control the application rate, with this it appears ground speed and pressure are the only means of application rate control?
My concern would be keeping the drum evenly coated for even application without over applying herbicide, which would be a substantial increase in cost over a large area as well as damage to grass or lawn from over application.
This would be effective for herbicides such as 2-4D that rely on systemic absorbtion to kill unwanted weeds, contact herbicides such as roundup that rely on contact instead of root absorbtion may not be as effective as spray where coating the entire plant/leaf is needed for effecient burn down.
Tank sanitation would remain the same, what about cleaning/sanitation of the roller in cases where different chemicals for different purposes may be encountered?

Hozen · Jun 14, 2010

Contrary to what CharlieS says, I actually think this is a pretty decent setup. Obviously, this is a yard implement and it stands to reason that jimgerken isn't going to use it to apply round up or anything else that is bad for the yard. I see it as a good way to save time in the spring... Roll out the yard from the winter freeze and also kill the spring weeds in the process. Seems like a win/win. Due to how surface tention of water works, I think the drum would stay coated fairly evenly (as even as the nozzles spray) during use once the entire drum was wet. I know this method would do wonders for getting close to flowers without the risk of overspray or drift. Nice work.

jimgerken · Jun 15, 2010

CharlieS said:
Interesting concept. With a conventional sprayer ground speed, nozzle size and system pressure control the application rate, with this it appears ground speed and pressure are the only means of application rate control??

"Calibration" of the roller applicator is the same as any sprayer applicator with "nozzles". Flow rate is determined, applicator width is measured and ground speed factors in to determine the area you will cover, then the amount of herbicide to go in each tankfull is calculated. The big variable eventually becomes ground speed. Holding a constant proper speed is hard on a garden tractor, whichever type of applicator you are pulling. Last week I used the roller applicator version #1 with oversized tank over most of my lawn. Over about 2/3 of an acre of lawn I used 14 oz of 45% Amine based 2-4D. Cost was $1.40. This week I see I missed a few strips, the clover is in full bloom in those strips. I would say that for the money in herbicide that application was a big success.

CharlieS said:
My concern would be keeping the drum evenly coated for even application without over applying herbicide, which would be a substantial increase in cost over a large area as well as damage to grass or lawn from over application. ?

The drum stays wet all the time. The 0.040" diameter holes in the applicator bar are 1 inch apart and they pour on the drum near the top, so there is ample opportunity for the liquid to spread out nicely. Even if I errored by a factor of ten (TEN TIMES THE AMOUNT OF HERBICIDE I NEED ! ) my whole 1-acre lawn would cost only about $20 per application. At that ridiculous rate I might notice some burning. Hehehe

CharlieS said:
This would be effective for herbicides such as 2-4D that rely on systemic absorbtion to kill unwanted weeds, contact herbicides such as roundup that rely on contact instead of root absorbtion may not be as effective as spray where coating the entire plant/leaf is needed for effecient burn down.?

Made for 2-4D, but I will be trying the roller with Roundup in the driveway to kill grass growing in the gravel.

CharlieS said:
Tank sanitation would remain the same, what about cleaning/sanitation of the roller in cases where different chemicals for different purposes may be encountered?

Easy. There will be little trace of anything on the roller after a quick rinse with the garden hose. All the plumbing gets the usual rinse and running with fresh water, then draining for storage.

Hound Dog · Jun 23, 2013

I realize this is a few years old . . Yours is the only one I've found or my search methods need improvement . .

I have some questions such as:

Is there a reason for the .040 holes an inch apart?

Are you controlling the pressure in the delivery pipe to prevent spraying or to control the 'drip"?

Is there a difference on where the drips hit the drum to get complete coverage on the drum?

I have a 48" x 18" plastic/nylon lawn roller full of sand and parts from an extra Fimco 15 gal sprayer
and they need to be introduced to each other.

jimgerken · Jun 24, 2013

Hound Dog said:
I realize this is a few years old . . Yours is the only one I've found or my search methods need improvement . .

I have some questions such as:

Is there a reason for the .040 holes an inch apart?

Are you controlling the pressure in the delivery pipe to prevent spraying or to control the 'drip"?

Is there a difference on where the drips hit the drum to get complete coverage on the drum?

I have a 48" x 18" plastic/nylon lawn roller full of sand and parts from an extra Fimco 15 gal sprayer
and they need to be introduced to each other.

Hole size: It was a first pass guess that works well. I didnt want the holes so small they would plug, and not so small that they would spray hard and cause misting and chemical drifting. I figured I could drill them larger if needed. Havent changed them.

Pressure control: Notice in the pictures, there is a return tube to tank. The pump pumps to the fluid delivery tube and t the return tube in parallel. so no real pressure develops in the delivery tube, but it certainly flows out well. I used the smallest pump I could buy at the time. You could rig it different if you had a different pump. Again, this was a guess, and I planned to insert a ball valve in the return to tank line if needed to improve the flow to the delivery tube. No valve was ever needed though, it just works fine this way.

Delivery point on drum: this is a good question and should be explored. I figured it should be at or near the top of the drum, and it works fine here, spreading completely over the surface.

Good luck, this project still works well for me, hopefully you will build one too. Post pics and writeup here is you do.

Hound Dog · Jun 27, 2013

Mine isn't as pretty as jimgerken's applicator. I ran a half tank of water through it around the yard and I think I'll add a ball valve to the supply line to the drip tube as it seemed to go pretty fast. At first it didn't seem like the drips would cover the roller but as it rolled a couple of feet, the entire roller was wet. I forgot how small a .040 drill bit is and broke it half way through so some of the holes are .041.