When I unpacked the rocket man metal impact sprinkler head, I thought someone at the factory had accidentally packed an early example of a Russian steam-punk pistol instead of a garden sprinkler.
This thing was heavy with fearsome engineering, from coiled springs and deflector shields to trip levers and nozzles.
It looked like it could fire a small nuclear warhead at least 5km into enemy territory.
Its real job was much more sedate — to water a small flower garden halfway down our narrow backyard triangle.
For a few weeks, I sat on the verandah and watched it work. It was a curiously satisfying thing listening to its tschik-tschik-tschik staccato rhythm spit water across the garden. I felt like a master of the mechanical universe.
Then it stopped spitting. It came to a sudden halt and sprayed a single 10m-high jet in one direction, which might have been acceptable if it wasn’t pressure-washing the neighbour’s shed.
Now, engineering and mechanical logic are not among my strong points, but if the gauntlet is thrown down, I’ll pick it up.
My early commando training in the forests of Wales told me to approach the water spray from behind to avoid soaking. I randomly poked the diffuser pin. Nothing happened. So, I jiggled the deflector shield a bit. Nothing happened. Then I got wild and slapped the trip lever around a bit. The thing returned fire by spinning around and catching me with a cannon spray up the back of my shirt as I ran away through the marigolds. Then, it returned to its 10m airborne water jet.
As it wasn’t responding to my usual approach of “when in doubt, clout”, I surmised it was time to get scientific.
So I went straight to YouTube and found a whole universe of amateur impact sprinkler experts just like me. They were also soaked from head to foot, just like me.
Using their water-logged tips, I lowered the pressure of the tank pump, cleaned out the rocket man nozzle and adjusted the rotation levers. It was still stuck at one 10m-high spout.
Now things got serious. Using Newton’s second law of motion, which is force equals mass times acceleration, I calculated there wasn’t enough high-peak torque being generated to overcome the static friction of the rotator arm. It took me several days, a bottle of gewürztraminer and a whiteboard of algebra to arrive at this conclusion.
I made all the necessary hair-trigger adjustments using a set of World War II bomb diffuser instruments I found at Dookie’s Military Emporium.
When it came time to test my theory, I stood well back and turned on the water pump. The result — an 8m-high water jet. This was progress in diplomatic relations, so fuelled by success, I attempted an on-the-spot adjustment of the friction collar.
The thing responded with Machiavellian cunning and hit me with a 100 psi blast in the face, which sent me reeling backwards into the California poppies. This was my Poland moment, and I was now at war. I retreated to the verandah to consider a Normandy invasion plan and to change my clothes. As I write, we are still at war, although the idea of living under a fascist 8m-high water spout is becoming more appealing every day.
