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I have a small and very awkward shaped piece of lawn. In 2009 I installed 6 Hunter MP1000 rotators and they worked just fine, but left three areas around the edges under-watered. So I bought three more rotators and am now installing them. Two have fitted in fine (another MP1000 and an MP corner), but for one area I bought an MP side strip, to do an area about 4 ft x 26 ft along my driveway. I have located this rotator 4ft+ from the driveway and pointing "outwards", rather than next to the driveway and pointing "inwards" because I didn't want to drive over it by accident. But this leads to a problem.

I have initially turned the rotator down to its minimum, but it still sends water about 1.5 ft onto the driveway, which of course is a waste. I had thought it would be more accurate than that, and a smaller width of strip. I'm also finding it difficult to set the angle of the strip correctly so it is parallel to the drive.

Has anyone had a similar problem? If so, how did you overcome it? One obvious way is just to move the rotator another foot back from the drive, but I am reluctant to keep digging trenches in an established lawn unless I know I need to.

Also, the ring adjustment that changes the angle on MP1000s, what is its purpose on an MP side strip?

Any help would be appreciated. Thanks.

Quoted from "Kiril"

What body are you using?

I am using the standard (as far as I know) Hunter Water body. Thinking about it, I think my problem may lie with the pressure - it is perhaps higher than I thought, in which case the area will be larger than I expected and I just have to move the rotator a little further from the drive.

But I am still wondering if others have found that the area watered is more elliptical than rectangular (though hard to define precisely, obviously) and what the ring adjustment does. It says somewhere that it adjusts the right edge in case of curved strips, so perhaps that is why I don't appear to have a rectangular area - but I haven't been able to figure out how the adjustment works exactly.

Thanks.

Quoted from "kosterirrigation"

You always need to use a PRS (pressure regulating model) spray body for the MP series nozzles. Hunter makes a body specifically for the MP nozzles regulating the pressure at 40psi MPR40

Look for the grey cap on top.

Quoted from "Kiril"

If you want to maximize your radius reduction, you need to put it on a body with 30 PSI regulation (ex. RB 1800 series with PRS)

These comments are very helpful thanks - I wish I had known this before. I bought the rotators at my local irrigation shop in Sydney and they supplied the bodies without any comment to me about there being different pressures. I guess I just got the 40 psi model by default, as you say.

But I solved my problems by experimentation.

The way I figured it out was to leave the rotator in the "wrong" location, put buckets over the other rotators so they didn't interfere, and then let the side strip rotator spray onto my concrete drive. I used surveyors chalk to mark out the spray area for different adjustment settings (easy to do on the drive, but would have been difficult on the grass). That enabled me to see that:

(1) Ring adjustment: If I turn the ring to the left, the side of the area is straight (i.e. the area is a rectangle). If I turn it fully to the right, the side of the area is curved and the area is like a wide flat U shape with the rotator at the bottom of the U. The Hunter literature hints at this but doesn't say so. So I needed the ring turned to the left.

(2) Location: Since I was working at minimum 'radius' I needed to move the rotator 0.5m further away from the drive. (Of course, had I known, I could have got the 30 psi body, but my solution works OK).

So it seems to be AOK now, but I think I'll email Hunter to suggest better documentation for the side strip and for the body pressure. Thanks for your help and the explanations, which helped me understand the whole deal.