EEs learn that knowledge and experience in electronics does not
translate into hands-on experience in other fields.
Way back in the
late 1970s, fresh out of school, I worked for a very small custom
electronics company. We made controls for heavy industries such as
steel mills, offshore oil rigs and mining. .
In steel mills, the cast bars would cool and have surface cracks.
The surface was ground off with grinders to reach clean steel before
rolling. These machines had large 300HP motors with huge grinding
wheels. Hydraulics controlled the wheel position and therefore the
power and amount of steel removed. Other hydraulics ran the steel back
and forth under the wheel on what looked like short flatbed railway
cars. Our controls were a mix of analog for the wheel position control
and Motorola's 6800 series of 8-bit processors (all code written in
assembler!) for the steel bar positioning.
As always, we designed and made the controls and shipped them to the
mill. Once the hydraulics, mechanical apparatus and our electronics was
installed, we would go to commission our electronics. Invariably,
something would fail. A hose would break (wonderful fountains at
1500PSI!), a fitting would leak, a valve would jam, a belt would be
thrown. Big red shutdown buttons were always nearby--and used. .
Late one evening we were busy trying to finish off an installation.
The hydraulic control valve that raised and lowered the grinding wheel
jammed. The three of us--my boss, a millwright and me--climbed the
stairs up the tower to check to see what was jamming the valve and
holding the wheel up. Judicious tapping with a wrench did nothing. The
valve would have to be replaced. The hydraulic cylinder was holding up
a heavy mechanism with a heavy grinding wheel, the valve controlled the
It was the end of a long day and us electronics folks were
not thinking clearly about hydraulics. Gathered around the valve on the
catwalk, we helped the millwright loosen the valve. Quite predictably,
it came loose and let loose a torrent of oil as the wheel dropped. We
were soaked in oil. Fortunately it was not hot and of course the pumps
were off. After the initial shock, a quick check that we all survived
intact. We laughed at our stupidity as we wiped oil out of our eyes. We
wiped away more oil and more again. No rags so we used our sleeves.
We stopped laughing as we noticed that none of us could open our
eyes with all of that oil running over our faces. The mill was closed
except for us--no shift that night. We sat there on the catwalk rubbing
our eyes and eventually, chuckling at our mistake, we climbed down.
Disaster dodged. .
We survived intact. Knowledge and experience in electronics does not
translate into hands-on experience in other fields. I now leave the
mechanical engineering to mechanical engineers, the software to the
coders (I do write test code and sometimes that gets used, much to my
chagrin). I find most people surprisingly competent at their job,
whether it be a millwright or PCB assembler. I can wield a soldering
iron but the best solderers are those who wield them eight hours a day.
I can change a hydraulic valve but would greatly prefer a millwright to
do it. Maybe we should have noticed that our millwright was tired or
not confident in his work. Maybe we should have questioned the safety
aspect. Maybe we should not have tried to rush to finish commissioning
our controls. Maybe, maybe. Live and learn. .
My designs these days are a few orders of magnitude faster than the
6800 series, have progressed from ±15V supplies to +1.2V to +5V,
use a fraction of the power and are always SMT. Thanks, but I can pass
on the good old days of electronics from a few decades ago.