I can't help thinking you're over complicating things. You're talking about a distance of "6.5metres" Would it not just be simpler to move the sprinkler from one spot to the other?
I want to put them in the ground permanently so that the garden is covered in one go. I may even get a timer later. I then won't need to move anything.
Do you need to water the garden that much? If you do then there may be better solutions than using sprinklers which are a very inefficient way to water the garden. Plants need water at their roots, not sprayed over their leaves where it can evaporate away without doing any good. For a semi-pemanent solution I would look at an irrigation system with individual drippers or small sprinklers for under the plants that really need it. A seeper/soaker hose would also work well in that situation.
A bit of an off the wall solution which I found worked in one of the houses I had - water either very early in the morning or very late at night - I am meaning somewhere between the hours of midnight and 5 AM. Water pressure will be significantly higher as all your neighbours will be asleep and not using it!! Try it - costs nothing and takes minutes to try.
'Optimism is the faith that leads to achievement' - Helen Keller
I didn't think of water pressure being different at certain times of the day. Totally logical though! Although, I do check if there's water going into the drain to realise my wife is in the shower again!
That said, I usually water the lawn at those times anyway but for a different reason; it's cooler at those times so the water doesn't evaporate as much or quickly.
I'm at the stage of giving up now. What was once a simple project has turned out to be more hassle than it's worth. The annoying thing though is that it almost works but doesn't have any consistency. It might be down to a slightly faulty sprinkler.
If it was simply down to bad water pressure and there was no way of the project being successful until it got boosted then fine. At least I know where I stand, but I get the feeling that with an adjustment here and there such as a better hose, fitting or sprinkler - it would work. The problem is, I don't want to spend the money to find out if that's the case. It's a risk and now not worth it. Right now, both sprinklers are pulsating the right amount of water but one or both do not rotate, or get stuck. The pattern changes.
Anyways, thanks for all your help and advice, I really appreciate it.
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