Played about in the garage, like you do, and found that if there's more than three bits of tape on an old motorcycle harness.... its just easier to make a new one than fix the old... Got quite good at it too.
So when a friend asks me to have a look at his Triumph T140... I thought " Great my first real job on someone else's bike..."
His problem was that when you pulled the brake lever both rear indicators glowed..... not the front... just the rear pair..... which is quite strange, sort of impossible, in itself....
So... seat off... all connectors unplugged... and I go to get my meter....
My mother came in and wants her scooter out... so we moved the T140...... pulled the brake lever.... like you do.... and the rear indicators glowed.....
Well I look at him and he looks at me cos nothing is connected... no power to anything on the rear end....
"What have you touched lately" I asked..... "Had the tank off to do the valves....." he said
SO off come the tank, with a bit of a struggle and find that the harness had been crushed against the frame....
If you apply pressure onto a wire/ cable it alters the insulation value... and the power just leaks through... and it will always find its shortest path to earth...
Which in this case was down the frame.. around the chrome rail and through the rear indicators...
Impressed that both rear indicators glowed evenly...
First job.... first lesson.... Bad Earth or "The Path of Least Resistance"
So...If your headlight is a bit dim.... check out the tail light connection... A bad earth can be absolutely anywhere...
And with electrics.. anything is possible...
Which leads me onto my second story....
During my 15 year stint at Cranes (Crane Fluid Systems) I had many jobs but the majority of my time was spent setting an operating CNC lathes in the bronze section...
My first day on the CNC's was with Peter... a brilliant machinist and a great man to learn from..
He says to me... "don't care if you come up to me covered in soot with a bent piece of machine in your hand... you must tell someone when things go wrong... what did you press.. what were you doing... etc... for it may be your fault.... but it may also be the machines...."
How right that saying proved to be...
Nice job but crap machines... especially the Stuart Davis ones I ran..... Cranes bought several Stuart Davis machines from their bankruptcy sale... Should have been an indicator of quality that one...
So I'm working away at this "200" model. Basically is a large rectangular metal box...... with a sliding door for access..... and a boxed in monitor on an arm next to the door....
I hated this thing.... not because of the cramped access to anything.... not because of the crappy way it worked.... but because of the fact, to me, that it had a sense of humour....
You may run of a hundred pieces or a thousand but first you have to set it... You could spend twenty minutes or a couple of hours doing this... and what was this machines party piece.... why did i hate it so much....
Well you have just spent x,y,z time setting it up... you set the IP (the initial position it starts from).... you run through the program manually... you alter the offsets to make things the right size.... and you put it into auto and run the first piece off...
When it finishes the part.... the chuck (holding the part) and the turret (holding the tooling) head back to there relative stops, ready to start again... But.... But.....
But just as they hit the stops it goes "Click" and the screen goes blank..... and everything is gone...... The program... the tooling offsets... even the base data that runs the machine... wiped out in an instant....
And this happened time after time.... I hated that machine... but it did make me laugh... it could have happened at any other time... but no it just had to wait right tell the end...
Cranes paid a fortune for an engineer to come and see what was wrong... but he always went away saying "its in the wiring not the hardware and until it blows up......."
He changed circuit boards.. he changed relays and boxes I have no idea of what they did.... but within a month it was "click" ...... mutter...... mutter... mumble.... I hate this bloody machine... AGAIN..
And then the inevitable happened..... And it was as spectacular as it was impossible....
I am setting up the machine again and about to put a tool into the turret when I heard "CLICK"...
Almost got my hand clear before the turret spun round.... funny feeling having your fingers stretched.
So just stood back and watched this... impossible thing... impossible because when you are setting and the door is open there's a whole raft of safety interlocks that stop anything moving... killing you...
But here I was watching the chuck spin up.... slow down... change direction... spin up again.. all very slowly and at minimal revs... but moving all the same...
The turret is slowly sliding back and forth along its bedway..
But the most amazing thing was the screen...... It was writing data.. gobbledygook.. but data... and then changing pages.... switching between offset, program and machine data pages..... and writing even more data on itself....
I call over a couple of other setters who stand there opened mouthed.... as they never believed half the things I said this machine did....
I walk round to the maintenance bay and up to a certain Mr Jones, who I have had many an argument with over this machine... and his usual answer was.. its impossible.. or... cant do that...
So I say to him... come and have a look at this... its moving by itself with the door open.... Guess what his answer was..... Yup... "It's Impossible"... so I literally drag him round to the machine..
Well the look on his face was a picture.... It was like watching David Armand doing the "there's so much going on section of his mime to Torn" he was just pointing to this and pointing to that with his mouth wide open....
After a couple of minute he just turns to me and says "Sorry Paul", to me, "and that's impossible".... as he point again to the turret..... "that's impossible".... as he points again to the chuck..... "and that's Bloody impossible" as he points to the screen....
Well the management came down... half the site came down... as Mr Jones put a barrier around this machine and left it running over the weekend.... because this was Friday and the engineer would not be here till Monday..
"Well" he says "perhaps the thing will blow itself up over the week end and maybe they'll but something decent"
It did not destroy itself... as much as I wished it would.... and on Monday the engineer arrived.. and he sat, having a cup of tea, watching this.. show... he even recorded it...
Then, finally, he opened up the rear doors to find a row of blackened circuit boards... which he replaced... and fired up the machine again....
It worked... bugger.... He said " might happen again as I think its in the wiring".... Bugger....
"Don't think it will be quite the same though as what I just watched was impossible"... Bug...... Eh!
"Why do you think I recorded it... the guys back at head office would never believe this one"...
Speechless....Still hate that damn machine.... and it was still running when I left... and it was still dumped all its info on occasion too.....
So... another lesson learnt.... with electrics, computer or otherwise, if it wants to do something... it will do it regardless of if your in the way.....
A point made clear a couple of years later... when I was doing a time study on a different machine there...
The operator loaded a part in to be machined.. pressed the start button... and this 50mm boring bar should have come forward and then down.... but it decided to come forward... and then keep on coming forwards and punched a BIG hole right through the plate steel bulkhead.... Bit of a loud bang that one... She jumped... I laughed.... and told her... "See... told you these had a sense of humour"
No comments:
Post a Comment