Weed Garden Sprayer

Weed Garden Sprayer

My wife and I bought a weed garden sprayer several years ago to try to get ahead of the weeds that invariably grow up in the Right of Way (ROW) of our railroad. I have not seen anyone else’s sprayer in action so building one would have to be done one piece at a time. I have been told that necessity is the mother of invention, but my ability to think in abstract thought was never part of my education system—there have been times that I thought the mother of inventions abandoned me outside the local church and I was raised by a machine. Some people call what I do “Trial and error” but it is very possible that my errors multiply rather than divide. Making parts over several times is a way of life.

Having said all that, I was finally able to get a car together that WORKS. This is the perfect Weed Garden Sprayer for your railroad right-of-way.

I became acquainted with several large scale modelers here in KY when we first got started in hernia gauge. Joe Holbrook and Don Saager gave me a number of ideas on what might work for a sprayer car, but it was Jim O’Connor who gave me the very important piece of this working MOW machine puzzle, that of having the spray heads in a curtain enclosure close to the track so there would be no overspray.


Photo 1
Photo 1 – The Frame

I started the weed garden sprayer with the tank from the sprayer outfit. Rather than try to make a new tank,

buy another pump, and who knows what else, I took the sprayer apart and figured out how long to make the car to contain the curtain on the front, the tank on the rear, and the pump and battery behind the curtain. It turned out we needed a car 5’ long, so when I ordered the steel for the side rails I got two pieces of 1”X2” channel 4’ long, thinking I would lower the battery down an inch or so. That turned out to not be needed, but making 4’ long channels into 5’ long channels was not going to be easy so I put the ½”X1” channel in and welded them up. I used some 1”X1” tubing for stiffeners for the frame and a piece of angle for the rear beam. The front beam is a 1”X2” channel.

Photo 2 - The Frame
Photo 2 – The Frame

The underframe is the standard 1/8” X 1” X 2” tubing 61” long with the same size tubing for the bolster assembly. Photos 1 & 2.  I used Titan (Former Mountain Car Company) trucks under this car. These are nicely made with steel wheels & axles, cast side frames and bolsters with a 1/8” thick bearing plate welded to the frame to give the trucks some “Wiggle room” and make the car more of a three legged stool.

Painting the weed garden sprayer – Sometime back I discovered that automobile undercoat paint works really well for steel and cast iron where they will get wet. This stuff does not need primer and it really does the job. I paint each sub-assembly before the final assembly is made unless I am welding parts together. In that case I just paint the corners and edges carefully and let it go. Photo 03

Photo 3 - Paint
Photo 3 – Paint

Photo 3A
Photo 3A – metal cutoff wheel

Cutting these parts became an adventure all its own. I tried several methods then stumbled upon a metal cutting blade from Milwaukee that would cut steel up to 3/8-inch thick. Since I do not have any machine tools, just a collection of hand tools, this method works for all sorts of necessities in large scale railroading. Photo 3A, making switch points, cutting steel for a freight car, and other needs. The shapes can be cut to any length or size with this magnificent blade. The pieces of the curtain were cut out using the table saw and welded together.

Once I had the frame for the weed garden sprayer on the trucks I was able to mount the curtain on the front of the car. Figuring out how tall to make the curtain was a matter of firing up the sprayer head assembly and holding it above the floor with the pump running. It came out to be 11” above the floor, so the curtain would be 12” tall, 30” wide (To clear other equipment in the car barn, but I did not think of that when I designed the 30” dimension, it just barely cleared a boxcar on an adjacent track by 1/2?) and to get enough clearance inside the curtain I decided to make it 10” from front to rear. Once that was done, I mounted the sprayer heads in and gave it a test. Photos 04 & 05.

I discovered that the first sprayer nozzles I bought from Tractor Supply were too large and the pump would not keep up with them. I returned them and got a finer set of nozzles which proved again that trial and error can be made to work. Photos 06 & 07. The second set of nozzles were perfect for the weed garden sprayer.

Photo 4 - Sprayer Heads
Photo 4 – Sprayer Heads

Photo 5 - Sprayers Working
Photo 5 – Sprayers Working

Photo 6 - Sprayer Head
Photo 6 – Sprayer Head

Photo 7 - Sprayer Tip
Photo 7 – Sprayer Tip

Once I had things operating the way I thought would be best, it was time to test the whole machine to see where the spray went on the ROW. Photos 08 & 09. We bought a gallon jug of Turf Mark from Southern States. (We only needed a quart but they only sell it in this size.) You do not need much in the tank to paint things blue, so we have a 10-year supply.

I installed a switch at the rear of the car to be able to shut the pump off when we got to areas that were already treated. Photo 10. Our engines are both RC controlled so maybe in the future, I can get one of those remote door key things and make the sprayer RC controlled as well, then there would be no need to ride behind the sprayer car or walk alongside it to control the heads.

I also put a hand held wand downstream in the discharge line to pick up areas outside the ROW if needed.

With the Turf Mark mixed in it was time to couple up to the GP-9 and test run the car. It ran perfectly, and the spray could be seen along the ROW just where we wanted it to be, but it was then we found that there would be overspray bouncing off the track and ties that would go outside the parameters of our desired finish, so a front had to be made and installed on the curtain to control that. Photo 11 That cured the problem, and if it becomes necessary to put a lid on the curtain, we can saw out a piece of plywood and just lay it on top.

Photo 8 - Turf Mark
Photo 8 – Turf Mark

Photo 9 - Spraying with Turf Mark
Photo 9 – Spraying with Turf Mark

Photo 10 - The on/off switch
Photo 10 – The on/off switch

Photo 11 - Curtain Front
Photo 11 – Curtain Front


What started out in 2012 was an 800’ circle of track around the barn and house has ended up in 2013 with an additional 1,200’ feet of track down the hill and around the pond. We knew that once we got a train running there would be no end to finding things to do. We are presently concentrating on detailing some rolling stock and building these sorts of MOW things.

I realized AFTER I tested it out that we were to get some freezing weather and I did not want to dump the water out, so I added some antifreeze and fired up the pump to get protection into the pump and hoses. It will spray out the same as the weed killer so it won’t be a problem later.

The weed sprayer operates as hoped for, it certainly was not because it was engineered and thought through, drawn up, and built from a set of plans. I just put a few pieces of steel together and this is what came out.   No it wasn’t what happened to the children of Israel when Moses came down off the mountain and Aaron had put some gold in the fire and out came the golden calf, we are enjoying the railroading but we don’t worship it.

Change order #02, install cover on top of the sprayer curtain. Reason: Operator found that mist was rising above the curtain and blowing to areas it was not intended.

Change Order 2
Change Order 2

Further testing shows the cover works as intended.

Weed Garden Sprayer – Written by:
Ray Grosser
Locomotive Backshop, paint and car shop
1145 Linn Road
Eubank KY 42567-9574

Weed Garden Sprayer Bill of Materials –

  • Metal cutting saw blade and a table saw, safety goggles and gloves
  • Wire welder
  • Drills and drill bits, thread taps, assorted clamps and hand tools, assorted button head cap screws to fasten parts together, – flat head cap screws to secure the deck to the frame
  • 2.1 GPM 60 PSI 12 Volt pump (Tractor Supply about $60)
  • 3 each sprayer nozzle bodies and nozzles, and 3 each fine mesh screens to protect the heads (Tractor Supply)
  • Three brass tees (Lowe’s)
  • Two pieces of 6” long brass pipe and one short nipple between the two center tees (Lowe’s)
  • Two brass Ells (Lowe’s)
  • Shut off valve for the sprayer head if you want to use the wand (Lowe’s)
  • Sprayer wand and length of hose to work for what is needed
  • Pipe to hose fittings and some stainless clamps to fit
  • 12 Volt battery, wire and a switch to operate the pump. (NAPA $65)
  • 1/2″ tubing for connecting the sprayer and wand to the pump (The Greenzilla air hose is really great stuff for this and now you can get fittings for the ends to make any length you want)
  • 1/8” X 1” X 2” X 8’ steel tubing for center beam and bolsters
  • 1/8” X 1” X 2” X 10’ channel for side sills
  • 1/8” X 1” X 2” X 32” channel for end framing of car body
  •  1/8” X 1” X 1” X 32” square tubing for bracing of the car body
  • 3/4″ X 16” X 60” plywood for the flooring
  • 14 gauge Cold Rolled Steel, enough to make the curtain. I used an offcut from a steel supply place that was 30” X 48”.
  • 3” X 24” of 10 gauge steel for the pump stand
  • Trucks of any type can be made to work
  • One coupler of any make or type that will work with what your railroad has
  • Capacity for abstract thought, Oh Brother Where Art Thou?

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