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-   -   Regarding ELECTRICAL THEORY BY JOSEPH LUCAS (https://www.pprune.org/tech-log/508241-regarding-electrical-theory-joseph-lucas.html)

SStreeter 12th Mar 2013 22:43

< I never realised that Wipac was part of Lucas >

I don't think they were. This link suggests that they are still going strong under that name:
About Wipac - Wipac

Agaricus bisporus 13th Mar 2013 12:16

Er - I think most people know that calling someone a name related to fruit is somewhat different to a name related to sewage.

I respectfully suggest that if you were to call, say, an African or an Asian race "Sewage" - short for for Sewage Farm - a direct equivalent to calling someone a septic tank - on the basis of some fanciful connection to a "rhyme" you would find yourself correctly and rightly buried in all kinds of trouble - for being nastily racist. So why/how is it OK to call Americans that? Is it becoz they is white?

Does not compute.

Anyway, racism apart septic is a thoroughly nasty and offensive term, you wouldn't dare to use it to an American's face would you? It is grossly unpleasant and thus not acceptable by any normal standards of manners or decency.

bubbers44 13th Mar 2013 12:45

As an American I accept septic as a normal way of disposing of waste. Not offensive at all. Now the Florida Keys has a brand new sewer system so septic systems are gone. Two years ago that was the only way to dispose of waste. We had the same system on our farm growing up. Why do people get so up tight about nothing? My polish roomate knew every polish joke and loved to tell them. Learn to laugh at yourself, it makes you healthier.

DozyWannabe 13th Mar 2013 13:37


Originally Posted by Agaricus bisporus (Post 7739870)
Anyway, racism apart septic is a thoroughly nasty and offensive term, you wouldn't dare to use it to an American's face would you?

Can and have - only in the age-old context of expressing affection between male friends by using insults though. I wouldn't use it to a stranger, just as I wouldn't call a stranger a :mad:er, :mad:pot, :mad:hole or :mad:nozzle! ;)

Rhyming slang can bite you if you get into the etymology though - A lot of people use "berk" thinking it's fairly innocuous, I hear kids use it and as a kid I even heard teachers use it on occasion. I doubt that'd be the case if it were more widely known that "berk" is a contraction of "Berkeley Hunt"... :}

blind pew 13th Mar 2013 15:38

AB
 
Perhaps you would prefer another rhyming slang
Thick as a ....
Just going for a ....
Or maybe you just don't understand semantics?

ACW599 13th Mar 2013 17:49

Speaking with an electronic systems designers' hat on, the idea of spraying WD-40 around electrics willy-nilly doesn't strike me as wholly wise. As the MSDS makes clear, WD-40 is nothing more than a mixture of white spirit and mineral oil. Neither is particularly good for either the galvanic properties of conductors or the long-term insulation properties of many plastics. Quite where WD-40 acquired its stellar reputation is a mystery.

If you want to disperse water and keep condensation out of an engine bay, a silicon/PTFE spray will do the job effectively. If you want to clean low-voltage or low-current connectors, propanol and a toothbrush works well.

syseng68k 15th Mar 2013 18:41


If you want to disperse water and keep condensation out of an engine bay, a silicon/PTFE spray will do the job effectively. If you want to clean low-voltage or low-current connectors, propanol and a toothbrush works well.
WD40 is petroleum based, so rots rubber and is also inflammable.

While I still have a can or two, my preference is also silicon spray. The
cheapest way to buy it is to look for "Silicon Mold Release Agent". Basically,
silicon grease in an aerosol.. Fixes the old style distributor caps for good and
also prevents electrolytic corrosion in multipin auto connectors...

syseng68k 15th Mar 2013 18:50

cockney steve, #44:

@syseng. You' Sir, are a true masochist. trying to stop the noise of an Alfa rusting, whilst struggling to make the engine run with that wonderful brown MM bakelite distributor cap which had built -in tracking.(the earlier form of theft-prevention which pinched the term.)

Well, everyone knew that the bodywork came free with Alfas, but where else
could could you buy a car with twin cam alloy engine, twin Weber carbs,
5 speed gearbox, limited slip diff and properly located axles for a few hundred
pounds ?. Yes, they all needed work, but the performance made it worthwhile and
provided forced education in the gentle art of mechanics :O...

kilomikedelta 15th Mar 2013 21:35

The gentle art of mechanics
 
Ah, the gentle art of mechanics. It should be a qualification for certification for every mechanical engineer to disassemble an engine down to each bolt and piston ring and rebuild it to hum (I've done a few) as it should be for every computer engineer to rebuild a wonky motherboard (and debug a peripheral driver) and every physician to be a hospital patient (been there too). One can't be a real engineer or physician without experiencing the practice of one's profession. Unfortunately, management MBA's are only trained by case studies of the latest corporate wheeze (most of which went bankrupt five years later) and can only relate to the sizzle and not the steak (viz. the latest verbiage from Boeing PR).

Uplinker 15th Mar 2013 21:56


WD40 is petroleum based, so rots rubber and is also inflammable.

While I still have a can or two, my preference is also silicon spray. The
cheapest way to buy it is to look for "Silicon Mold Release Agent". Basically,
silicon grease in an aerosol.. Fixes the old style distributor caps for good and
also prevents electrolytic corrosion in multipin auto connectors...
Thanks for the info, syseng. (Pedant alert: I know you mean flammable). I have sprayed WD40 all over the car engine bay for the last couple of winters and the results are great. The rubber looks new and shows no sign of perishing. Or am I suddenly going to be stranded by the roadside one night?

I have always wondered how spraying silicon etc onto electrical connections makes them work. Apart from driving off water, one would expect it to cause bad connections by it's insulating properties? (and I speak as an erstwhile electronics engineer).

kilomikedelta 15th Mar 2013 22:48

Uplinker: The OED accepts inflammable and flammable as equivalent. Pedant alert: the OED (Oxford English Dictionary) tries to keep English speakers communicating efficiently. The in- prefix of inflammable means supporting. A monolayer of silicone on electrical contacts would only be an insulator for microvolt potential differences.

Chu Chu 16th Mar 2013 12:52

I once saw a toggle switch burn up not long after someone decided to lubricate it with silicone spray. I've always figured the cause was resistance from silicone on the contacts. But I could, of course, be wrong.

deptrai 16th Mar 2013 13:15

if anyone is experiencing problems with Lucas electrics (they are actually A/C, with a random frequency), you may need this replacement part

http://www.mez.co.uk/smoke2.jpg

" Lucas Replacement Wiring Harness Smoke kit, P/N 530433, along with the very rare Churchill Tool 18G548BS adapter tube and metering valve. "

this one was for sale on eBay, but these original service kits are hard to find

syseng68k 16th Mar 2013 13:46


I have always wondered how spraying silicon etc onto electrical connections
makes them work. Apart from driving off water, one would expect it to cause
bad connections by it's insulating properties? (and I speak as an erstwhile
electronics engineer).
Auto connectors are usually not the best quality and have tin plated
contacts. They also often carry significant current and have voltage
drop across the contacts, so it only takes a little moisture to produce
electrolytic corrosion and the "white powder effect". The contacts slide
on mate and there's pressure between the surfaces. A thin film of silicon
spray forms a bubble around the mating surfaces, while at the same time
being easily penetrated by contact pressure to form a good contact.
Modern autos typically have dozens of connectors, many of which are
exposed and even if they are rubber sealed, this perishes over time to
let the damp in.

I tend to keep my cars for years, even decades, so I perhaps see more
of this sort of problem than others...

Uplinker 16th Mar 2013 16:19

I've spent years cleaning electrical contacts with various products, and have always wondered that.

I also keep my cars for too long and know about the problems of which you speak. :rolleyes:

Thanks kilo, that must have changed then, because it used to mean the opposite - or was that an urban myth? (Like I said I did issue a 'pedant alert' !!)

FlightlessParrot 17th Mar 2013 01:14

Language pedant
 
Inflammable.
The problem is that the prefix in- has two origins. One is Germanic, and intensifies the meaning of the compound; the other derives from a Latin prefix in-, which negatives the meaning of the compound. Normally, people know which is which by context.

AFAIK, the original word was "inflammable" with intensifying in-. But, of course, some people took the wrong meaning, so the word "flammable" was invented, for labelling purposes. For me, the word is "inflammable" in normal usage (as in "highly inflammable" or "an inflammable personality"), but I'd for sure put "flammable" on a bottle of solvent.

P.S., the true pedants will notice that I have somewhat simplified the in- thing; and also that "flammable" did exist in the 1800s, but was rare until its adoption on elf and safety grounds.

compressor stall 17th Mar 2013 08:11

Habitable and inhabitable follow the same logic.

DozyWannabe 17th Mar 2013 16:00


Originally Posted by syseng68k (Post 7743824)
WD40 is petroleum based, so rots rubber and is also inflammable.

Which is why I only ever use it on connectors with plastic housing (and inside the distributor cap). I use regular switch cleaner on rubber connectors, seal with insulating tape and put Vaseline on the tape.

That said, I think in more modern vehicles the "rubber" on things like HT leads etc. is actually synthetic.

syseng68k 18th Mar 2013 00:01


Ah, the gentle art of mechanics. It should be a qualification for certification for every
mechanical engineer to disassemble an engine...
Something like that might have been the case in the old days, when there was more
stress on the practical, rather than abstracting the whole process off into some cad
package or other. Not that i'm against cad, just the oppposite, but how do trainee
engineers get the practical experience these days ?. Working with hand and machine
tools should be part of the process and there's nothing like hands on working with
metal to get an instinctive understanding of it's characteristics and limits. You can't
get that from cad packages and "design rule sets" are by nature generic and not
necessarily optimum...

If you are similar age, then our generation cut our teeth on motorcycles, often fixing
by the roadside, before somehow getting cheap mot failure cars fixed and through
the mot. So many people these days seem so completely devoid of clue w/respect
to anything mechanical and would rather pay garages 50-100 ukp / hour, for the
most trivial of faults.

Starting to sound like grumpy old sod, but what happened to scientific curiosity,
the right stuff and pursuit of excellence for it's own sake ?. Just one more pointer to
the general decline and fall of Western civilisation :sad:...

Uplinker 18th Mar 2013 15:54

I agree with you Chris,

I never cease to be amazed when I see a car with a flat on the side of the road, and instead of the guy changing the wheel, he is standing there clueless and calling someone on his phone.


Same goes for gals too by the way - everyone should know how to change a wheel. Unless she's nice looking, in which case I might stop and help.....


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