Travelling Gun Irrigator

[worntorn]

I built this about twenty years ago and it has had lots of use. So far the only major repair cost has been replacement of the plastic hose. The hose weighs about a ton when filled with water so there is a lot of pull and stress on it as it wraps onto the drum. After about 15 years the hose started to break down.

Power is from a 240volt 360 to one gear motor. That drive goes into the large 40 to one gear reducer and then there is a further gear reduction in the drive chain and sprockets. Total reduction is 24,000 to one.
On the opposite side a drive chain comes off to run the powered fairlead assembly. The fairlead is geared to move exactly the diameter of the pipe for each revolution of the drum. When the fairlead gets to the edge of the drum, it reverses and heads back the other way, much like some fishing reels with geared fairleads.

The travelling cart moves at 1foot per minute and waters a 180' circle. I run it mainly at night to reduce evaporation. In a 12 hour shift it winds all the way in and shuts of automatically. The pipe is 800' long so it irrigates approximately 3 acres per night.

Power is supplied to the field by an underground 240 volt supply line. I put it in the same trench as the 4" high pressure water supply line. The water supply is 60 gallons per minute at 110 PSI, from an irrigation well we drilled.
There are 5 risers located in the fields. From these 5 risers the machine will reach the entire pasture area, about 20 acres.

Glen

[ScratchStart]

That is awesome, so the line on the drum is power or water? looks like water line, I just don't understand what the red hose is for? or does it just drag an extension cord around with it? lot's of math in that reduction and gearing, good job man.

[Tritium]

The red hose looks like it is from the water source.

Thurmond

[DaveO]

I read this yesterday and had so many questions I will spare you the trouble of dumbing it down for a city boy. Although maybe I could start with "Built 20 years ago from a kit, or from scratch?" Anything you built 20 years ago that has required only routine maintenance is by definition a job well done.

I was confused by the red hose too- Worntorn's post says power and water are delivered in a trench, presumably along the water gun's route, but I haven't worked out how that figures into the 800 foot length on 3" hose that collects on the reel. And I haven't worked out how it travels on just two wheels. Does it travel in a laser straight line, or can it tolerate a bend in the road? You can run it, unattended, for 12 hours straight?

[Tritium]

It looks to me like the sprinkler is on skids and the unit "reels" the sprinkler in as it runs (the big unit pictured would be stationary). That is the only way I could see it working. I could be wrong though.

Thurmond

[worntorn]

You've got it Thurmond. The machine part sits in one place and slowly (12 hrs) reels in the black hose with the sprinkler gun cart at it's end.

The red hose is the water supply. It has quick connects at each end, one goes to the machine the other to a male coupling on the end of the riser. The trenches which I dug(then filled after installation of lines) for the water supply and electric supply don't follow the route of the gun cart. The supply lines take the shortest route possible to get out to the various locations needed to reach all of the irrigated area.

I built the machine from scratch. A neighbour had a manufactured machine which he kindly parked for winter storage in my shop yard. I borrowed some ideas from it and made up the rest. That machine had a water powered drive motor, so part of the water flowing thru the machine did the work of winding in the hose. This looked too complicated to make so I opted to try an Electric drive and gear reductions. When I realized the reduction needed was 24,000 to one, I was pretty sure that the 1/2 hp motor was plenty. I was less sure that it would start under load on 500' of #10 wire @ 240 volts. This is the distance to the riser that is furthest from the power panel in the barn. It starts easily. I think with the 24,000 to one reduction that 1/2 hp motor would pull a house over!

When the machine has wound in and shut itself off after irrigating an 800 x 180' strip, I unplug the electrical cord, unhook the red supply hose, pick the gun cart up a foot or so off the ground. I do this with a little boat winch that lifts via the boom you see in photo 3. Then I back the tractor in to what looks like a trailer hitch setup at the other end of the machine and pick it up with the 3 point hitch. This part of the job can be done from the tractor seat in a few seconds. Once I have the machine connected to the tractor, I pull it to the next riser location, or just turn it around 180 degrees and pull the hose out 800 feet in the opposite direction.
I should explain that part too. For the pullout, the reel gets put in neutral and the hose gets pulled out 800 feet with the tractor. For that I use the same 3 pt hitch crossbar arrangement that was used to move the machine around, only this time I hook onto the sprinler gun cart. Again the connection is done from the tractor seat in a few seconds.

Hope that helps explain it a bit better.

Glen

[ScratchStart]

Ok, that makes more sense, I just had it in my head that the whole unit traveled, and the sprinkler was mounted on the cart.

that solves all sorts of problems for me... electrical and supply are stationary, just the cart moves to each of the supply places... gotcha!

that thing is super sweet