Intro: Poor-mans Automatic Sprinkler.
How to build a poor-mans automatic sprinkler. Forget the cheap battery powered ones. The battery ones always fail when your not home, ending up with wasted water and mushy sod.
Here is how to put together a cheap, reliable, rugged, automatic above-ground sprinkler set up. If your thrifty, you can put it together for less than $30.00!
Step 1: Bill of Materials
One (1) 3/4 Sprinkler Valve - $12.99
Two (2) Male Hose Barbs - $3.47
One (1) Sprinkler Transformer - $14.96
One (1) Wall Timer - $5.97
Six (6) Feet of old hose - Free!
15 foot Extension Cord - $9.99
One (1) Y Shut off (Optional) - $8.97
Teflon Tape - $0.99
Zip Lock Freezer Bag
Heat shrink tubing or Electrical Tape.
Sprinkler of choice.
That comes to a total of $57.35. The other battery operated units I have bought cost about as much. They all let me down.
The transformer I had sitting around from a prior job. I have heard you can use just about any voltage (AC or DC) to trigger the valve. I chose to use this because I know it wont damage the valve. Keep in mind that if you run an incorrect voltage you increase the risk of damaging the solenoid or starting a fire. You're on your own if you try a different transformer.
The hose, grab it out of your scrap bin. Alternatively, scrounge one on trash day. You really only need a couple feet.
Hose ends. I buy brass fittings with hose clamps from Big Lots. They cost as low as a dollar if you do a little searching. The Y adapters can be had for a couple dollars from the same location.
There are several sizes of valves. For some reason, it seems that the 1" valves are cheaper. The 1" valve will not work with a regular hose without reducers. Search out the 3/4" valves. These can be had from $11 to $13 dollars.
As you can see, you can easily drop the cost of the unit down below $30.00! Rock on, lets proceed.
Step 2: Assemble
Attach Both male hose fittings to the length of hose.
Generously wrap the threads on one side of the hose with Teflon tape and thread it into the sprinkler valve. Use pliers to snug it down nice and tight.
Generously wrap the threads on the Y shut-off with Teflon tape. Thread the Y-Pipe onto the inlet side of the sprinkler valve.
Cut the two bottom corners off the ziplock bag. Plug the transformer into the timer. Plug the timer into the extension cord. Run the transformer leads out one side and the extension cord out the other. Wrap the plastic around tightly around the wires and zip tie the bag to the wires.
Connect the transformer to the valve. Its not polarized, so just connect the wires (solder if you prefer), and heat shrink the connections.
Connect the Y shut-off to your desired faucet and the hose end to your desired hose. Set your timer and plug in your plug. Seal up the zip lock bag.
Step 3: Testing and Enjoying
Turn on the water and check for leaks. Open the Y and verify the valve pressurizes. It should not allow water to pass. Fix any leaks now. Turn your bleed screw and see if your sprinkler kicks on.
Plug it in, set the timer. Switch the timer to on and the valve should open. Switch it back to timer and enjoy.
Set the timer to go on early in the morning (Mine comes on for half an hour at 5AM. This will give the water a chance to soak into the ground before the afternoon heat. The timer will help you save water by soaking when most effective. Switching to a 7 day timer would allow you to save even more water by alternating days.
Here in San Antonio, if our aquafer drops below a certian level, we enter stage 1 water restrictions. This means we can only use automatic sprinklers once a week. A 7 day timer would let me comply. Once my new grass takes root, I plan on dropping to twice a week watering schedule.
Upgrades, Mods, tweaks?
7 Day digital timer - Give you programmable 7 day watering schedule. This is my next upgrade.
Water proof box. - Probably a wise investment. I intend to scrounge one of these from the junk pile at work.
Daisy Chain Sprinklers - Get all those dry spots.
Multiple valves - Water front and back yards.
Well, enjoy your lush green lawn.