Yesterday I went down to the hydro for the first time in a month because I could tell from the control board that there was increasing fluctuating output. It sounded a bit grating but couldn’t see a problem until I shut it down and gave it a good shake. Just a little rattle on the turbine shaft meant one of the bearings was shot. I keep a couple on hand so could fix it right away, but instead of requiring a gear puller to drag it off, I could pull it off by hand. Bugger! The shaft had been turning in the bearing for some time and had been ground away. I presented the new bearing to the shaft and had to hammer it on which is good, until it got to the proper seated position and it was minutely slack, which is bad. Due to some movement in the position of the bearing, I backed it off until at least a little bit of it was tight. Bodging at its worst. But wait! I have more shameful remedies to share. When the wear and rattle gets big enough, it is possible to use a shim. For those of an engineering bent, a shim is some thin material you jamb in to make the bastard fit. For bearings, I have found that a broken carpenter’s tape can do the trick. It is hard spring steel and thin. Cut just enough of the tape to go round the shaft, wrap it cup side up around the worn shaft, and flog the bearing on with a large lump hammer. Tight as a duck’s arse. For now, I am holding this technique in reserve for when the shaft/bearing fit gets as bad as a brick in a shirt sleeve.
Of course there is a genuine engineering remedy. This is not buying a new part as this equipment was a one-off from 32 years ago. I could dismantle the turbine, take the shaft into an engineering shop in Atherton, have the shaft built up with stainless steel welds added to the shaft and then turned down to size on a lathe. Perfect, good as new. This has two disadvantages. First it would cost money. Dear readers who know me would appreciate the horror in which I hold this solution. Second, I would be at the mercy of a hugely competent, but disinterested company’s job list, and could expect to wait until more lucrative jobs were completed before my pissy little repair was looked at.
So having got the hydro producing again I retired to bed basking in the glow of my own ingenuity. Only to be awakened next morning by the hum of the hydro going over-speed, which means it is not producing electricity. Usually, I can’t hear it at all. Double bugger! What did I FUP? (to differentiate from FU which I definitely didn’t mean). It was a totally unrelated failure. A connection to the slip-rings had become loose and burned out. This is because I couldn’t get UNF 5/32 inch nuts. These are tiny brass nuts of an archaic British thread that are not made anymore. I have scoured the world via google and concluded that the 32nd inch sizes have been discontinued, probably for decades, and only sixteenth sizes were now available. So I had bodged up some nuts by tapping the nearest size of metric threads into a little nut. I had been very careful when tightening up not to strip the threads, but had not got a secure enough connection. After about a month of use the connection had built up resistance which heats it up leading to catastrophic melt-down mode. Sometimes bodging comes back to bite you in the bum. About 20mm of wire remaining as the rest burned away. All this takes place in a tiny space that normally rotates at 1500RPM. Like doing surgery in a mouse’s earhole. I find a very small diameter bit of copper pipe (gads, I love my junk), to join the wires and crimp the new to the old, squashing it together with vice grip pliers. The tiny stripped thread nut I also delicately crimped to an oval shape to be able to tighten up. There is a good chance this latest bodge will last a decade.
In the couple of days this electrical disaster was happening, my e-mail was also falling apart. I could not send any e-mail to anybody with a hotmail address. The Mailer Daemon reported a ‘block list’. Apparently hotmail was blocking my ISP. Why? doesn’t make much sense. So I opened another account using my own domain and a completely different server but the result was the same. I suspect skulduggery way beyond my pay grade. Either hotmail is attacking me (most unlikely) or others are attacking hotmail (much more believable), or a system fuck-up (very believable). My apologies to those with hotmail addresses who have received no reply from me.
I am much more at home with mechanical failure than web problems.
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