Water, water, everywhere

The Infinite Weekend was three years old the other day!

Annual Summary:

• Much the same as last year really
• Still reasonably healthy and having lots of fun
• Thoroughly recommend retirement over working!

And so, onto a project report (or two).

I mentioned the garden irrigation project a while ago.  It took a while to get all the pipe connectors - it turns out that they never turn up if you haven't actually ordered them - and since then progress has been a bit fitful (what with the drinking and everything) but we are fully operational now.  As a result, the garden, which would otherwise be rather dry, is covered with black pipes, like this:

Exminster Desert

There is 16mm pipe all round the edge, and 6mm pipe to each of the terminations, which are adjustable sprinklers, if you have enough water pressure to actually sprinkle.  We are a bit low on water pressure, because I am feeding this lot (a total of 50m of 16mm pipe and about 40 sprinklers so far) from the house's built-in rainwater collection system, which delivers its precious prize using a pump in the garage.  It's able to supply them all, but only at a dribble.  It's a rare situation where dribbling is genuinely OK, but fortunately this is one of them.

The whole lot is turned on and off by this sandwich box:

sandwich box

SANDWICH BOX!

which contains the water control solenoid valves out of the old washing machine (see Sawdust).  I'm using two of them in parallel to maximise the flow rate.  I had to make the fitting on the right, because you can't buy dual entry bulkhead mounting Hoselock connectors off the shelf, for some unaccountable reason.  It's basically a brass tap connector on the outside, and a threaded adaptor, with a ground-down t-piece attached inside it using copious amounts of hot glue gun glue, on the inside.  With some big washers.  Anyway, it doesn't leak, so hoorah!

Inside the house, I acquired a single channel USB-controlled mains switch, which is a little printed circuit board with a socketed chip and a relay on it, which your PC thinks looks like a COM port when you plug it in.  It's made by KMtronic and they cost £26.40 new, but I found a second hand one on Ebay for a fiver.

There is already a laptop on the breakfast bar in the kitchen to do the actual controlling, so the obvious place to mount the switch was right there, under the breakfast bar.  So I needed a suitable box...

I did look into buying one, but I couldn't find anything really ideal, so I made one instead.  Since it's got mains electricity inside, I thought it should be be made of nice insulating plastic, and I came up with this:

It's made of square plastic rainwater downpipe (from stock, natch).  Inside it looks like this:

The bosses are rivnuts, held in with hot glue gun glue (as is the front panel).  The board sits inside like this:

leaving lots of room for the mains cable and strain relief.  Two screws hold it up under the counter top and all is wonderful.  I did think about fitting a plastic shield round each of the mounting screws so that I could claim the whole thing to be double insulated, but pragmatism won me over in the end.  I am pretty sure it won't electrocute anyone unless there's a massive earthquake and simultaneous flood, in which case all bets are off, and so, in all probability, is the electricity.

So far so good; but idly looking up washing machine water control valves on the internet, I made the unexpected discovery that they are not rated for continuous operation!  They can manage a mere two minutes on, before needing the following three minutes to cool down.  Who'd have thought it?  Anyway, we are going to be software controlled, so that's no problem.  A bit of Python, a one-line shell script, and a few days farting around, and we can set the thing for some period of irrigation using a command like

$ water 15

to get 15 minutes of on-time, spread across the required 36 minutes.  Actually, the rest periods are good all round, because the pump in the garage doesn't like continuous operation much either, and cuts out sometimes when you're using the hose. Whereupon it has to be manually reset (by me), which isn't in the spirit of automation really.  So, the lazy valves are OK with me.

The next issue is, what should the user interface look like?  I foresee a web-based thing with cron in the background for controlling regularly-timed events, but it's far from settled.  Obviously, since it's software, anything is possible.  I'm also considering a rain gauge...

Also in the garden, the lovely Jackie requested a two-way bird feeder hanger which would thwart squirrels and cats.  I leapt into action with the aluminium post from the for-sale sign from our last house (previously used in a special tool for single-handed lifting of the brick-filled manhole cover there, and thence returned to stock) and some tube from a scrap aluminium hang-glider frame, kindly donated by a friend who still does that sort of thing.  I was going to "weld" it using those new rods they advertise on the internet (more like a sort of aluminium brazing really) but sadly, I couldn't get enough heat from my crappy blowtorch.  I even made a new, bigger burner tube but to no avail.  Anyway, here it is in bolted-together (and spray-painted copper) form, appearing to erupt out of a sun lounger:

gibbet

As you can see, I went for the classic gibbet format.  It's mounted on the fence, to be away from the terrace, and it's quite tall; so it needs to pivot forward so that the lovely Jackie can reach the feeders to reload.  Thus:

reloading the gibbet

To hold it upright, I thought a ball catch would do the trick:

...has only got one ball

but it turned out that the frequent Exminster tornadoes were to much for it, so I had to add this at the top:

which I have to say seems a bit ridiculous, but it works.  Actually it has a rather satisfying finality about it when you push the pole back upright.  I have no idea why, but I have several such door latches in stock, new and unused.  The door handle is one from our old house which was replaced in the refurb there.  Plenty more of those in stock too...

gibbet erected, and secured by door handle

The left hand feeder is for sunflower hearts, which goldfinches enjoy spreading over the garden with their specially adapted beaks.  Sparrows, of course, prefer spreading the conventional mixed seeds.  You can see them both doing it in full-motion, exciting video (!) here.

And finally, as if this post doesn't have enough pictures in it, here's something we saw in a car park recently when we went out for some "exercise":

man exercising his batmobile

I didn't have the heart to tell him that one of his rear wheels was missing.