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On Tue, 25 Apr 2017 20:16:22 +0100, "Benderthe.evilrobot"
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"John B Slocomb" wrote in message
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On Mon, 24 Apr 2017 22:17:14 -0400,
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On Tue, 25 Apr 2017 07:42:21 +0700, John B Slocomb
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On Mon, 24 Apr 2017 19:51:41 +0100,
"Benderthe.evilrobot"
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On Sun, 23 Apr 2017 22:06:05 +0100,
"Benderthe.evilrobot"
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"Emanuel Berg" wrote in message
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I finally got the 1/2" torque wrench,
28-210 Nm, not even made in China, but in
Taiwan! Eh... I guess it depends who you ask if
that is China or not 
It has a locking screw, a torque setting
handle, a scale (Nm as well as "FT-LB", some
English unit I take it?) - it also as a
locking lever on top just like an ordinary
ratchet, so it can go both ways, clockwise and
anti-clockwise.
The torques only work in the
clockwise direction. So if the
locking (ratchet) lever is set the other way,
it is just a ratchet, right? Well, in
the manual it says:
Note: Never use the torque wrench to undo
nuts, bolts or other fasteners as this will
damage the ratchet mechanism and the
calibrated settings.
So how does that add up? Is it only OK to use
the anti-clockwise pull to insert things, which
would require a left thread? (And it would be
just a long shaft, with the torque not
in effect.)
As for me, I don't plan using it for anything
but as a torque, because I have other, less
expensive ratchets and spanners to do the
everyday stuff. But of course, I'd like to know
what it means.
It also came with a certificate with data on
the calibration and in the manual it says it
should be recalibrated at least every
12 months.
Calibration is irrelevant if you don't follow the
rules to the
letter.
Most torque settings I've seen were for dry
threads - any stray
lubricant
and you might even twist the end off at the
correct torque.
---
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Torque specs vary considerably by application.
Some are given as
clean and dry, some are given as lubricated with
oil - some are
given
cold, and others hot. That said, I personally have
never run across
a
torque spec that was so "close to the edge" that
torqing with "stray
lubrication" would cause immediate failure of the
bolt by twisting
off
the end.
However, that said, most of my wrenching has not
been on bicycles
but
on automobiles and agricultural and construction
equipment which may
be slightly more "overengineered" or "overbuilt"
Bicycles tend to have less things you can twist the
end off.
Its common on motorcycles, but mainly pulling the
threads out of alloy
castings. Its pretty rare to strip an engine down
so far that you can
put
the castings in degreasing plant - torquing the
engine case bolts with
oil
left in the holes is a very good chance of
stripping the threads.
As for stripping engine bolts, the Honda factory
used to install
fasteners so tight that a normal person couldn't get
them out without
an"impact driver". A tool that I never even saw
before the Japanese
invasion.
The lock washers were very effective where used, and
the Phipips style
bolts were incapable of delivering enough torque to
breat them loose
without camming out - the Hammer Impact driver solved
that problem
I believe I've read that the "Phillips" headed screws
in a Japanese
motorcycle are not actually "Phillips" but some
Japanese standard that
didn't quite match the screwdrivers we had in the U.S.
Which probably
didn't help either :-)
That's the *whole* cause - just grind a tiny bit off
the point of the
screwdriver bit and it fits just right.
The bits on my Impact driver fit perfectly without
grinding.
Note I said Philips "style" (I know, I mis-spelled it)
bolts.
Some of the early Jap stuff didn't use Cadmium plated
bolts either -
W10 imploded and I had to start over with a replacement
news account. So
back to old name.
The japs were the worst of the lot for cadmium plated
fasteners.
The very toxic cadmium rubs off on your hands and is
cumulative in the
body - it causes such acute osteoporosis; you can end up
fracturing ribs
just by coughing.
In the UK - nickel plated fasteners became fashionable
about the 80s. They
didn't do much about cadmium plated chassis in electronic
equipment until
RoHS.
AFAIK: cadmium batteries are exempt from RoHS - but
they've more or less
vanished from the shops anyway.
Cadmium is very nasty - wash your hands after handling
anything plated with
it!
from Cadmium, A Health Hazard Surface Treatment
C. Rehm
ESG
Einsteinstr. 174
D-81675 Munich, Germany
An object containing cadmium is not especially injurious
to health on
its own. No risk is involved simply by touching it.
A potential hazard occurs, however, when such objects are
processed
and high temperatures are generated.
Cadmium plating rubs off on your hands whenever you handle
cadmium plated parts and assemblies.
Many years ago they even used it on electronic component
leads to prevent oxidation - they used more aggressive
fluxes in those days.
Welding cad plated sheet steel is particularly dangerous -
the cadmium is vapourised and becomes airborne.
Usually the osteoporosis takes decades to start crippling
the sufferer - but I've heard of a repair technician
dropping dead after a couple of years from fumes using low
melting point cadmium based solder. The specific mode of
death wasn't announced.
The Japanese know all about it, they discharged industrial
effluent containing cadmium into heavily fished costal
waters. They even have a name for the disease - itai itai
byo. apparently its the noise sufferers make in their death
throes. As I mentioned previously - bones become so weak and
brittle, you can fracture ribs just by coughing.
Well then avoid it as you wish.
Many of us recognize the difference between metals and
reactive metallic organic compounds.
Zinc rich tablets are popular for symptoms of herpes
simplex and yet no one welds galvanize steel a second time.
Zinc can't be that toxic - its a usual ingredient of baby
powder.
Never heard of any warnings against welding zinc passivated
steel - only know of cadmium plating being very dangerous.
Fumes of burning zinc make your knees go soft as you vomit on the way
down. Don't try this at home.
When I was a kid, I liked throwing zinc batteries on the bonfire to watch
them explode - no such effect was ever observed.
Even one single exhausted battery would have more zinc than a pretty big
sheet of zinc plated steel - and would dwarf the amount of zinc vapourised
by a weld run.
Whenever you are working with galvanized steel it is important that
you take the necessary steps when prepping the metal before welding.
If you have properly prepped your metal before welding, you will help
reduce your exposure to zinc oxide fumes. While prepping the base
metal will remove the majority of the zinc from the surface of the
metal, the possibility of some galvanizing while welding may occur. A
common sign of galvanizing is the appearance of yellowish-green smoke.
Other signs are a white powdery particles in the air, and a white
residue around the weld. If exposure to large quantities of the
yellowish-green zinc oxide fumes occur, you may experience galvanize
poisoning, or metal fume fever as it is sometimes called. The
severity of your symptoms depends on the amount of time of exposure to
the harmful fumes.
Galvanize Poisoning
Symptoms of galvanize poisoning can be similar to flu symptoms. The
onset of symptoms typically begin shortly after exposure to zinc oxide
and may include a mild headache and nausea. If you have a more severe
case of exposure, your symptoms will be consistent to those you
experience when you have the flu. A moderate case of exposure will
result in symptoms including chills, shaking, a slight fever, vomiting
and cold sweats. If you begin to experience any of these symptoms you
should immediately stop working and get some fresh air. In severe
cases the symptoms may be so bad that you will have to go home until
they subside. The most severe cases of galvanize poisoning can result
in death. If you feel that your symptoms are worse than ever before,
you should seek medical attention at once.
Galvanize poisoning is often short and your symptoms should begin to
lessen within four hours of exposure. You should be completely
symptom free within twenty four hours. If you experience a stronger
exposure, you may still be experiencing symptoms up to forty-eight
hours later. We recommend upon exposure that you drink milk in order
to quicken your recovery. The calcium in milk helps remove the zinc
build-up from your body.
AND
Avoiding “Fume Fever”
Feb 09, 2011 by bakersgas in Uncategorized
Imagine you just finished up a day on the job, welding Galvanized
Steel. You head home, shower up, and grab a beer as you settle in to
watch the game on the tube. But then you start to feel kind of gross.
Your legs start to ache, you become really thirsty with a blazing dry
throat, and you start coughing and become congested, shivering all
over. Things get worse from there as you spike a fever, feel nauseous
and start throwing up. At the height of this two-day nightmare ride,
you even hallucinate and experience convulsions.
Is this the worse flu ever? Nope—you’ve just been hit by Fume Fever.
It’s pretty nasty stuff, but totally preventable and fortunately, it’s
not currently linked to any long-term health problems.
Galvanized Steel is coated with a thin layer of zinc, and zinc melts
at a much lower rate than steel, so when you’re welding Galvanized
Steel, the zinc coating is vaporized and turns into zinc oxide. When
you breath-in zinc oxide fumes, you develop what is commonly known as
Fume Fever. This usually happens 1-4 hours after exposure and
typically lasts for 1-2 days.
The good news is these nasty side-effects are totally preventable.
•Proper ventilation in your work area is the first, and most effective
way to prevent the inhalation of zinc oxide fumes. Most shops and
industrial complexes have effective ventilation and air filtration
systems in-place, and outdoor job sites are generally not a problem,
as fumes dissipate naturally outside.
•If you’re working in a confined or unventilated work area, wear an
approved respirator. Varying types of respirators are available, and
the level of fumes you’re exposed to will dictate the type of
respirator you need for a particular job.
**Never eat, drink or smoke in an area contaminated by zinc oxide or
any welding fumes.
***Always wash your hands thoroughly after you finish welding, and
definitely before you eat—zinc oxide can be extremely poisonous if
ingested