DIY drip irrigation

[Worth1]

Originally Posted by spereira

I stopped by Menards this evening after work..bought the 29.00 "starter kit"

I figured this would get me started plus I like the idea of buying locally..instead of on line. I can buy additional supplies that will fit the Rainbird system on Amazon.

this is all new to me so the learning curve will take time.

Steve

Congratulations on getting started on drip.
Rainbird makes good stuff.

Worth

[Stvrob]

One thing Ive found about drippers is that if you are hooking them to a regular hose spigot it is very awkward to adjust the flow (especially if you are on a well and your pressure switch cuts on at 30 and off at 50). The hose spigot valves are just too coarse for the kind of adjustment required. What I do is take a few quarters and drill 1/32", 3/64", 1/16" etc holes straight thru them. They will fit snugly in the female hose adapter just under the hose washer. Basically, you need to kill off most of the house pressure and bring it down to the 10 to 15 psi range. For just a couple of 1 gph drippers, the 1/32" hole might be about right. For a bunch more drippers, a bigger hole is called for. Mostly its trial and error, and i just keep an assortment of different hole sizes handy.
I know most of them are supposed to be pressure compensated, but I see alot of variation in their individual flows if they have more than about 15 psi pressure on them.

[zeuspaul]

Originally Posted by Cole_Robbie

I use drip tape. I have a fertilizer injector, but have only put very soluble ferts in it. I have considered building a pipe and dripper system so that I can have easier access to the emitters to see if they are clogging up. That would let me run organic ferts through the injector, a lot of which tend to be goopy and cause clogs. If I clog up my drip tape under black plastic, I'm not going to realize it until the plants start to wither.

A lot to think about. I am going to keep my runs short so a problem on one row does not affect another. It would be simpler to use a long run spanning multiple rows of tomatoes but I think running one drip line down each row with a valve at the beginning of each row will serve me better.

I'll keep my existing main 1 inch PVC line and tee off to a 1/2 inch PVC and 1/2 inch brass ball valve (overkill I know). Then run 1/2 drip line down the row with drippers every 12 inches ending with a flush valve. I am guessing the flush valve will help keep the drippers clean. I worry about clogged drippers but I plant extra tomatoes because I have all kinds of failures. If I lose a few more plants I can live with that. I will be installing a filter at the beginning of the entire system. The PVC will be buried or covered with mulch.

I'll take another look at drip tape. It is about half the cost but is thinner and probably won't last as long.

Originally Posted by Worth1

After you posted this I did some serious research.

What I found out was much of this but not all is interchangeable.

Worth

I am looking at a site with .620 OD, .670 OD, .700 OD and .710 OD 1/2 inch tubing. Sprinkler Warehouse sells Rainbird and DIG universal fittings which fit all of the above. However if one uses compression and barb fittings be careful to check the specs.

http://www.sprinklerwarehouse.com/Un...ngs-s/8116.htm

[Worth1]

Originally Posted by zeuspaul

I am looking at a site with .620 OD, .670 OD, .700 OD and .710 OD 1/2 inch tubing. Sprinkler Warehouse sells Rainbird and DIG universal fittings which fit all of the above. However if one uses compression and barb fittings be careful to check the specs.

http://www.sprinklerwarehouse.com/Un...ngs-s/8116.htm

I know, when I first started doing this several if not many years ago and saw the different sizes all called 1/2 inch I thought to myself, "You gotta be #!%&$ kidding me.
They make it off just a bit so you might have to buy their product.

I have bought many many $$$$$ worth of stuff from Sprinkler Warehouse.

Worth

[Cole_Robbie]

I replace my drip tape every year. Morgan County Seed, where I buy it from, says you can get two years out of it if you pick it up in winter and store it away from mice. This is in Missouri, I'm not sure if you have an off-season in San Diego. I don't know why mice eat drip tape, maybe when chem ferts are injected, it tastes salty?

[Worth1]

Originally Posted by Stvrob

One thing Ive found about drippers is that if you are hooking them to a regular hose spigot it is very awkward to adjust the flow (especially if you are on a well and your pressure switch cuts on at 30 and off at 50). The hose spigot valves are just too coarse for the kind of adjustment required. What I do is take a few quarters and drill 1/32", 3/64", 1/16" etc holes straight thru them. They will fit snugly in the female hose adapter just under the hose washer. Basically, you need to kill off most of the house pressure and bring it down to the 10 to 15 psi range. For just a couple of 1 gph drippers, the 1/32" hole might be about right. For a bunch more drippers, a bigger hole is called for. Mostly its trial and error, and i just keep an assortment of different hole sizes handy.
I know most of them are supposed to be pressure compensated, but I see alot of variation in their individual flows if they have more than about 15 psi pressure on them.

You know you could just put a pressure regulator on it and you wouldn't have to mess with it anymore.

Here are a few like this.
http://www.sprinklerwarehouse.com/Dr...ors-s/1045.htm
Then there are the ones that fit on an irrigation valve.
http://www.sprinklerwarehouse.com/Ir...-p/omr-100.htm

[Cole_Robbie]

yeah, I learned that drip tape requires a regulator. They aren't kidding about that It works for about five minutes, then ruptures in very impressive fashion, rooster-tails of water fifteen feet into the air.

[Stvrob]

Originally Posted by Worth1

You know you could just put a pressure regulator on it and you wouldn't have to mess with it anymore.

Here are a few like this.
http://www.sprinklerwarehouse.com/Dr...ors-s/1045.htm
Then there are the ones that fit on an irrigation valve.
http://www.sprinklerwarehouse.com/Ir...-p/omr-100.htm

I notice they all cost more than $.25.

[Worth1]

Originally Posted by Stvrob

I notice they all cost more than $.25.

This one doesn't and it should fit your needs.
http://www.sprinklerwarehouse.com/Ad...r-p/18-007.htm

You can also get them that aren't adjustable for around 12 dollars.
http://www.sprinklerwarehouse.com/PR...prf-25-100.htm

Then there is home depot that sells them too.

Worth

[Stvrob]

I meant $0.25, the amount Im out for drilling a hole thru a quarter.

[Worth1]

Originally Posted by Stvrob

I meant $0.25, the amount Im out for drilling a hole thru a quarter.

That makes more since.

You are doing what I am doing with the valves I have with a more fine tunable flow control on them.
I have no need for the regulators either.

Worth

[Stvrob]

Originally Posted by Worth1

That makes more since.

You are doing what I am doing with the valves I have with a more fine tunable flow control on them.
I have no need for the regulators either.

Worth

Mostly its just me being cheap. Plus I know cheap pressure regulators can be pretty fussy too, particularly as the source pressure varies between the cut in pressure and the cutoff pressure. Those on city water would have a pretty stable pressure (normally) and that wouldnt be much of a concern.

[heirloomtomaguy]

Originally Posted by Stvrob

I meant $0.25, the amount Im out for drilling a hole thru a quarter.

Just so you know by drilling a hole through a quarter you are not changing the pressure at all. By drilling the hole in a quarter you are regulating the flow of the water and once the water ceases flowing you will be right back at the pressure you started with. The drip tape i use requires no higher than 10-15 psi no matter whether it is delivered through a 1/8th inch hole or a 20 inch hole or pipe in my instance.

[Cole_Robbie]

I was thinking the same thing - whether it worked would depend on the length of the run, and the amount of flow. With more emitters flowing than what could run through the quarter, it would work. With less, I think it would still back up and rupture.

[Stvrob]

Originally Posted by heirloomtomaguy

Just so you know by drilling a hole through a quarter you are not changing the pressure at all. By drilling the hole in a quarter you are regulating the flow of the water and once the water ceases flowing you will be right back at the pressure you started with. The drip tape i use requires no higher than 10-15 psi no matter whether it is delivered through a 1/8th inch hole or a 20 inch hole or pipe in my instance.

Sure it does. Certainly you would agree that a valve decreases the pressure downstream? All the hole does is act like a valve which is 1. Not adjustable 2. Has an extremely low flow coefficient. A hole in a quarter is a miniature version of a submerged orifice plate which has applications all thru industry.
I am not claiming it is actually a regulator, its just that the pressure drop thru it goes up with the square of the velocity thru the hole, so if you make the hole small enough, (thereby increasing the velocity), the pressure drop increases by the square. So even if the upstream pressure were greater, not much more water will fit thru the hole, and the downstream pressure wont change much. This is approximately what you want for a dripper, and only a high end regulator will be able to do much better.