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So this is where I write a long rant about thermal dynamics, and
somebody comes along to tell me how completely wrong I am...
My mum's old oven was always too hot. It would burn anything you tried
to cook to a cinder. My mum remains convinced this is because the
thermostat was faulty. This is nonesense because... IT DOESN'T HAVE A
THERMOSTAT.
The temparature control on the front just adjusts the size of the flame
(by adjusting how fast the gas is let in). There's no temparature sensor
beyond the one used to check that the gas has ignited.
I've told her this repeatedly. Her responce has always been "oh yeah? So
how come the oven doesn't just constantly heat up until it melts?"
The answer, of course, is: BECAUSE IT'S NOT A PERPETUAL MOTION MACHINE!
This afternoon, I sat down and worked out the whole thing. See, you
light a fire in the back of the oven, and it injects heat at a constant
rate. An oven is well insulated - that's why even with a relatively tiny
flame, it can reach a few hundred degrees Centigrade inside. But any hot
object inevitably looses heat.
As the oven gets hotter, it looses heat faster. Eventually, the rate at
which heat is lost equals the rate at which the flame is adding heat. At
this point, the oven now holds a constant temparature. No thermostat
required.
Adjusting the size of the flame changes the rate of heat injection, and
hence moves the steady-state temparature.
It's the same physics that causes an object to reach terminal velocity
in freefall, and why your car doesn't have an infinite top speed.
"Oh yeah? So how come the central heating system has a thermostat then?"
Well, our oven adjusts temparature by changing the size of the flame.
The boiler for the heating does NOT adjust the size of the flame - only
the duty cycle. Switching a flame on and off requires a thermostat.
More importantly, the inside of an oven is a few hundred degrees hotter
than the outside. If the outside temparature moves 10 degrees, it's not
going to change the steady-state temparature inside by much. On the
other hand, the temparature outside your house is normally much closer
to the temparature inside. So variations in outside temparature will
have a bigger effect.
On top of that, it doesn't really matter if your oven is 10 degrees
colder than you asked for, but it makes a pretty important difference if
your house is. So an oven needs less exact control than a house, and a
house has more significant variations to take into account.
I notice that electric cookers also use a thermostat. Again, this
appears to be because they modulate duty cycle rather than heat
injection rate, for whatever reason. (I presume it's just awkward to
smoothly adjust the level of a multi-kW electric pathway?)
Small question: The rate at which an object looses heat. Clearly this is
proportional to how much hotter it is than its surroundings. But is this
relationship linear?
From what I can remember, the temparature of an object approaches that
of its surroundings according to an exponential curve ("cooling curve").
The derrivative of an exponential is also an exponential, so that would
indicate that as an object gets hotter, it looses exponentially more
heat. Right?
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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On Sun, 01 Jun 2008 19:14:43 +0100, Orchid XP v8 <voi### [at] dev null>
wrote:
>So this is where I write a long rant about thermal dynamics, and
>somebody comes along to tell me how completely wrong I am...
I remember thinking the same as you when I lived with my parents
(quite a while ago) and I actually had a look inside. What I saw was
when you put the oven on the flame was quite large, between one and
two inches, after the oven had heated up. The size of the flame had
shrunk to being about a quarter of an inch. You probably cannot see an
open flame in modern cookers, health and safety etc.
Oh and if you Google "gas oven thermostats" you might be surprised as
you can find how to fix faulty ones ;)
--
Regards
Stephen
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> My mum's old oven was always too hot. It would burn anything you tried to
> cook to a cinder. My mum remains convinced this is because the thermostat
> was faulty. This is nonesense because... IT DOESN'T HAVE A THERMOSTAT.
Ermm, actually it does have a thermostat. Simply tested by wiggling the
knob while the oven is cold and observing that the flame size doesn't
change.
If it didn't have a thermostat then to set the temperature at eg 200 degrees
(I don't know what gas mark that is) the flame size would be so small it
would take 10 hours to get to anywhere near 200 degrees.
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scott wrote:
> Ermm, actually it does have a thermostat. Simply tested by wiggling the
> knob while the oven is cold and observing that the flame size doesn't
> change.
Interesting. On my oven, it does.
[There is some kind of sensor that detects whether the gas has ignited.
When you turn the oven on, it lets in a tiny amount of gas and ignites
it. Then, after a few seconds, the flame suddenly grows to full size.
Thereafter it remains at that size until you turn the oven off.]
> If it didn't have a thermostat then to set the temperature at eg 200
> degrees (I don't know what gas mark that is) the flame size would be so
> small it would take 10 hours to get to anywhere near 200 degrees.
That's an interesting theory.
OOC, any idea how much energy it takes to warm up 0.25 m^2 of air from
20°C to 200°C? (And how much energy is released when you burn some
methane...)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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On Mon, 02 Jun 2008 09:00:15 +0100, Invisible <voi### [at] devnull> wrote:
>
>Interesting. On my oven, it does.
>
>[There is some kind of sensor that detects whether the gas has ignited.
>When you turn the oven on, it lets in a tiny amount of gas and ignites
>it. Then, after a few seconds, the flame suddenly grows to full size.
>Thereafter it remains at that size until you turn the oven off.]
That is why the oven gets too hot. The thermostat is not working
properly.
You have found the fault, now all you have to do is fix it.
Well done.
--
Regards
Stephen
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> Interesting. On my oven, it does.
It's broken then. In a cold oven, any temperature setting significantly
above room temperature should cause the maximum size flame to be used. Once
the oven gets to that setting the thermostat should then regulate the gas
flow to keep that temperature.
> [There is some kind of sensor that detects whether the gas has ignited.
> When you turn the oven on, it lets in a tiny amount of gas and ignites it.
> Then, after a few seconds, the flame suddenly grows to full size.
> Thereafter it remains at that size until you turn the oven off.]
That is a different system, that is there to stop the gas coming out full
whack until the oven knows that it's actually ignited. Otherwise if there
is a fault (and the gas is not ignited) then you might end up filling your
house with gas, which is not such a good idea.
> OOC, any idea how much energy it takes to warm up 0.25 m^2 of air from
> 20°C to 200°C?
The specific heat capacity of air is roughly 1 Joule per gram per degree
Kelvin. So I make that about 45 kJ.
You probably want to heat up some of the metal inside the oven too...
> (And how much energy is released when you burn some methane...)
Googling "energy density methane" seems to give 55 MJ / kg.
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>> Interesting. On my oven, it does.
>
> It's broken then. In a cold oven, any temperature setting significantly
> above room temperature should cause the maximum size flame to be used.
> Once the oven gets to that setting the thermostat should then regulate
> the gas flow to keep that temperature.
Well, we've since thrown the old oven away. But the brand new one we've
got does exactly the same thing. And that has a mechanical thermometer
inside which shows me it's working correctly.
>> [There is some kind of sensor that detects whether the gas has
>> ignited. When you turn the oven on, it lets in a tiny amount of gas
>> and ignites it. Then, after a few seconds, the flame suddenly grows to
>> full size. Thereafter it remains at that size until you turn the oven
>> off.]
>
> That is a different system, that is there to stop the gas coming out
> full whack until the oven knows that it's actually ignited. Otherwise
> if there is a fault (and the gas is not ignited) then you might end up
> filling your house with gas, which is not such a good idea.
Uh, yah. I figured. ;-)
>> OOC, any idea how much energy it takes to warm up 0.25 m^2 of air from
>> 20°C to 200°C?
>
> The specific heat capacity of air is roughly 1 Joule per gram per degree
> Kelvin. So I make that about 45 kJ.
Right. I had no idea what the technical term for that is.
Now I simply *must* know if the specific heat capacity of oil is
significantly different from water... (Every time I make cheese
toasties, the cheese inside is hotter than lava! They should fill
storage heaters with that stuff or something...)
> You probably want to heat up some of the metal inside the oven too...
Oh, for sure. And I assume that there's some kind of air pathway to let
more oxygen into the oven too - and hence a similar pathway that lets
the hot air escape. I just wanted to get some idea "how big" the number is.
>> (And how much energy is released when you burn some methane...)
>
> Googling "energy density methane" seems to give 55 MJ / kg.
On the other hand, what the HELL volume of methane gas weighs 1 kg? ;-)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Stephen wrote:
> You have found the fault, now all you have to do is fix it.
>
> Well done.
Nah, we threw that oven away. ;-)
[Ever tried throwing an oven? It's ****ing heavy! And loud...]
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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On Mon, 02 Jun 2008 11:39:11 +0100, Invisible <voi### [at] devnull> wrote:
>Stephen wrote:
>
>> You have found the fault, now all you have to do is fix it.
>>
>> Well done.
>
>Nah, we threw that oven away. ;-)
LOL
>[Ever tried throwing an oven? It's ****ing heavy! And loud...]
No I just move house :-)
--
Regards
Stephen
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> Now I simply *must* know if the specific heat capacity of oil is
> significantly different from water...
I think it's actually lower than water.
> (Every time I make cheese toasties, the cheese inside is hotter than lava!
> They should fill storage heaters with that stuff or something...)
They use it for storage heaters and cooling electrical stuff because it
doesn't boil at 100 degrees and is an insulator.
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Orchid XP v8 wrote:
> Small question: The rate at which an object looses heat. Clearly this is
> proportional to how much hotter it is than its surroundings. But is this
> relationship linear?
No. The radiation of energy due to heat is proportional to the fourth
power of the absolute temperature.
Regards,
John
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>> Small question: The rate at which an object looses heat. Clearly this
>> is proportional to how much hotter it is than its surroundings. But is
>> this relationship linear?
>
> No. The radiation of energy due to heat is proportional to the fourth
> power of the absolute temperature.
And how about the conduction and/or convection of heat as a function of
temparature difference?
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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>> No. The radiation of energy due to heat is proportional to the fourth
>> power of the absolute temperature.
Also your item receives radiation from other objects nearby, and of course
the amount depends on the temperature of them.
> And how about the conduction and/or convection of heat as a function of
> temparature difference?
Conduction is linear with temperature difference, convection is more complex
because it involves fluid flow.
Also, bear in mind that the thermal properties (specific heat, conductivity,
emissivity) will change significantly with temperature, so it is really hard
to give a straightforward function of temperature.
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>> Now I simply *must* know if the specific heat capacity of oil is
>> significantly different from water...
>
> I think it's actually lower than water.
According to Wikipedia (which, obviously, is never wrong), the specific
heat of water is about 4.1 J per g per degree, whereas for parafin wax
(the only organic compound I could find) it's 2.2 - roughly half.
I'd be interested to know what it is for typical animal fat. And also
for sugar, actually.
At this point, I hypothesize that these substances remain hotter than
hot water due to the lack of evatorative cooling...
>> (Every time I make cheese toasties, the cheese inside is hotter than
>> lava! They should fill storage heaters with that stuff or something...)
>
> They use it for storage heaters and cooling electrical stuff because it
> doesn't boil at 100 degrees and is an insulator.
I would imagine the fact that it doesn't corrode metal is a fact too... ;-)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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>>> No. The radiation of energy due to heat is proportional to the
>>> fourth power of the absolute temperature.
>
> Also your item receives radiation from other objects nearby, and of
> course the amount depends on the temperature of them.
Which, I presume, means an object at thermal equilibrium emits and
absorbs equal amounts of radiation.
>> And how about the conduction and/or convection of heat as a function
>> of temparature difference?
>
> Conduction is linear with temperature difference, convection is more
> complex because it involves fluid flow.
>
> Also, bear in mind that the thermal properties (specific heat,
> conductivity, emissivity) will change significantly with temperature, so
> it is really hard to give a straightforward function of temperature.
OK. Well when I did some simple experiments at school, we found that a
glass of boiling water apporaches thermal equilibrium more or less
logarithmically. So I think we can safely conclude that thermal losses
increase at least linearly with temparature - even if the exact function
is hard to pin down.
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Invisible wrote:
> According to Wikipedia (which, obviously, is never wrong), the specific
> heat of water is about 4.1 J per g per degree, whereas for parafin wax
> (the only organic compound I could find) it's 2.2 - roughly half.
Actually, 2.5 for parafin wax, 2.2 for ethane, and 2.2 for gasoline. So
the only three organic substances present show a remarkable [and quite
possibly coincidental] correlation.
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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> Which, I presume, means an object at thermal equilibrium emits and absorbs
> equal amounts of radiation.
Yes, in a vacuum. In air or with some other material contact, you need to
include the conduction of heat too.
> OK. Well when I did some simple experiments at school, we found that a
> glass of boiling water apporaches thermal equilibrium more or less
> logarithmically. So I think we can safely conclude that thermal losses
> increase at least linearly with temparature - even if the exact function
> is hard to pin down.
Water is very stable thermally, for example it's specific heat varies by
less than 1% from 0 to 100 degrees. Other materials are far more unstable,
and when you have several materials together in a system it is even more
complex. Then add in that your heat source may be generating different
amounts of heat at different temperatures, and things are far from linear
once you get away from simple science experiments.
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> I would imagine the fact that it doesn't corrode metal is a fact too...
> ;-)
So long as it's sealed there isn't (any significant) corrosion. I imagine
the heating system you have at home has been working for several years,
probably several decades with water running round it the whole time.
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scott wrote:
>> I would imagine the fact that it doesn't corrode metal is a fact
>> too... ;-)
>
> So long as it's sealed there isn't (any significant) corrosion. I
> imagine the heating system you have at home has been working for several
> years, probably several decades with water running round it the whole time.
Actually no, it was fitted about 3 years ago. ;-)
What I *have* observed is that the water inside such systems is always
jet black, and usually stinks like hell...
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Invisible wrote:
>>> Now I simply *must* know if the specific heat capacity of oil is
>>> significantly different from water...
>>
>> I think it's actually lower than water.
>
> According to Wikipedia (which, obviously, is never wrong), the specific
> heat of water is about 4.1 J per g per degree, whereas for parafin wax
> (the only organic compound I could find) it's 2.2 - roughly half.
>
> I'd be interested to know what it is for typical animal fat. And also
> for sugar, actually.
>
Soybeans, which was the only usable result google gave me for "specific
heat of oil", have a specific heat of about 1.926 to 2.912 kj/kg-K
according to
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1745-4530.1999.tb00500.x
Sugar, according to
http://209.85.215.104/search?q=cache:B3m5sDbitg0J:www.solexthermal.com/assets/pdf/en/SolexCS_The%2520Solex%2520Heat%2520Exchanger%2520-%2520A%2520Better%2520Way%2520to%2520Cool%2520Sugar%2520Crystals.pdf+%22specific+heat+of+sugar%22&hl=en&ct=clnk&cd=4&gl=us,
has a specific heat of 0.31 kcal/kg.°C which is about 1.3kj/kg-K. (1
kilo calorie is 4.185 Joules).
And, for other chemicals,
http://www.engineeringtoolbox.com/specific-heat-fluids-d_151.html is a
good table.
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Sabrina Kilian wrote:
> Soybeans, which was the only usable result google gave me for "specific
> heat of oil", have a specific heat of about 1.926 to 2.912 kj/kg-K
> according to
> http://www.blackwell-synergy.com/doi/abs/10.1111/j.1745-4530.1999.tb00500.x
>
> Sugar, according to
>
http://209.85.215.104/search?q=cache:B3m5sDbitg0J:www.solexthermal.com/assets/pdf/en/SolexCS_The%2520Solex%2520Heat%2520Exchanger%2520-%2520A%2520Better%2520Way%2520to%2520Cool%2520Sugar%2520Crystals.pdf+%22specific+heat+of+sugar%22&hl=en&ct=clnk&cd=4&gl=us,
> has a specific heat of 0.31 kcal/kg.°C which is about 1.3kj/kg-K. (1
> kilo calorie is 4.185 Joules).
>
> And, for other chemicals,
> http://www.engineeringtoolbox.com/specific-heat-fluids-d_151.html is a
> good table.
All very much lower than the 4.1 for water, as Scott originally asserted.
Hmm, interesting. It must be that water cools faster because it
evapourates then...
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Invisible wrote:
> OOC, any idea how much energy it takes to warm up 0.25 m^2 of air from
> 20°C to 200°C? (And how much energy is released when you burn some
> methane...)
I don't know about air, but that's exactly the sort of question metric
is supposed to make trivial. One degree C heats one cm of water with one
<mumble> of energy. (Calorie?)
--
Darren New / San Diego, CA, USA (PST)
"That's pretty. Where's that?"
"It's the Age of Channelwood."
"We should go there on vacation some time."
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Darren New wrote:
> Invisible wrote:
>> OOC, any idea how much energy it takes to warm up 0.25 m^2 of air from
>> 20°C to 200°C? (And how much energy is released when you burn some
>> methane...)
>
> I don't know about air, but that's exactly the sort of question metric
> is supposed to make trivial. One degree C heats one cm of water with one
> <mumble> of energy. (Calorie?)
(Pedantic mode: 1 cm^3 or more precisely, 1 g).
It's likely a bit more complicated with air - it expands much more
readily than water does. But no doubt it's easy to calculate.
--
The next war will determine not what is right, but what is left.
/\ /\ /\ /
/ \/ \ u e e n / \/ a w a z
>>>>>>mue### [at] nawazorg<<<<<<
anl
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Mueen Nawaz wrote:
> (Pedantic mode: 1 cm^3 or more precisely, 1 g).
Yeah. I meant to type ccm. :-)
--
Darren New / San Diego, CA, USA (PST)
"That's pretty. Where's that?"
"It's the Age of Channelwood."
"We should go there on vacation some time."
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Invisible wrote:
> All very much lower than the 4.1 for water, as Scott originally asserted.
>
> Hmm, interesting. It must be that water cools faster because it
> evapourates then...
>
It could also be because the oil and fat in cheese has a higher
temperature then the water would. Or that what water is left has a much
higher boiling point when in solution.
For added fun, compare the energy in sugar water, say 1 kg of 87% sugar
by weight, at 125 C compared to 1kg of water at the same temperature.
Candy making is fun, if sometimes painful for reasons shown above, science.
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Invisible <voi### [at] devnull> wrote:
> On the other hand, what the HELL volume of methane gas weighs 1 kg? ;-)
>
That is actually a trick question.
The mass-part is easy enough: pure Methane consists of one C-atom (at 12g/mol)
and 4 H-atoms (at 1g/mol) for a total of 16g per 22.4 liter. Thus at regular
temperatures and pressures, you need 1400 liter of methane to get 1kg of
*mass*.
However the *weight* has to take into account buoyancy. Given an atmosphere that
consist mostly of N2 (weight 28g per mol) the buoyant force on a volume of
methane will exceed its gravitational force, i.e. it has a negative weight at
any volume.
I. e. it doesn't weigh anything - it rises up.
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>
> Yes, in a vacuum. In air or with some other material contact, you need
> to include the conduction of heat too.
>
And there can be a strong difference: Once I was experimenting with
tungsten wires as an electron emitter. Under vacuum (10^-9mbar) you could
push a current of about 4 amps to get a bright yellow glow - and an
accordingly strong emission of electrons. OOC I put the same wire in air,
connected to a lab power source driving a constant current of 4 A.
Result: only a faint red glow. And when you blew air past the wire -just
a little- it would stop glowing. And since the resistivity of metals is
proportional to the temperature, you could observe the cooling also on
the voltage meter of the power source. This setup can be used to measure
gas flows, and a similar setup is actually used in mass flow controllers.
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And lo on Mon, 02 Jun 2008 11:39:11 +0100, Invisible <voi### [at] devnull> did
spake, saying:
> Stephen wrote:
>
>> You have found the fault, now all you have to do is fix it.
>> Well done.
>
> Nah, we threw that oven away. ;-)
>
> [Ever tried throwing an oven? It's ****ing heavy! And loud...]
Out of pure curiosity did the suppliers of your new oven take the old one
away for free?
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
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Phil Cook wrote:
> Out of pure curiosity did the suppliers of your new oven take the old
> one away for free?
Actually no.
It's quite irritating really. I've been hearing all kinds of stories on
the news about people stealing metal. (Not to be confused with "steeling
metal".) Apparently one house had their roof stolen (?!), and a church
had their bell stolen. But *we* leave an old oven and a sink sitting on
our front lawn for a week or two and does anybody steal it? NO. In the
end we had to *pay money* for the Council to come and take it away... grr!!
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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And lo on Mon, 09 Jun 2008 11:31:45 +0100, Invisible <voi### [at] devnull> did
spake, saying:
> Phil Cook wrote:
>
>> Out of pure curiosity did the suppliers of your new oven take the old
>> one away for free?
>
> Actually no.
Was it pure gas or did it have an electric hob?
> It's quite irritating really. I've been hearing all kinds of stories on
> the news about people stealing metal. (Not to be confused with "steeling
> metal".) Apparently one house had their roof stolen (?!), and a church
> had their bell stolen. But *we* leave an old oven and a sink sitting on
> our front lawn for a week or two and does anybody steal it? NO. In the
> end we had to *pay money* for the Council to come and take it away...
> grr!!
Too hard to dismantle into useable parts for melting down.
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
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>>> Out of pure curiosity did the suppliers of your new oven take the old
>>> one away for free?
>>
>> Actually no.
>
> Was it pure gas or did it have an electric hob?
Nope, just gas.
[Did have an electric timer and temperature meter - but both of these
elements were Fraggle-rocked.]
>> It's quite irritating really. I've been hearing all kinds of stories
>> on the news about people stealing metal. (Not to be confused with
>> "steeling metal".) Apparently one house had their roof stolen (?!),
>> and a church had their bell stolen. But *we* leave an old oven and a
>> sink sitting on our front lawn for a week or two and does anybody
>> steal it? NO. In the end we had to *pay money* for the Council to come
>> and take it away... grr!!
>
> Too hard to dismantle into useable parts for melting down.
Er... a *sink* needs dismantling?? It's a sheet of metal! o_O
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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On Mon, 09 Jun 2008 11:31:45 +0100, Invisible wrote:
> NO. In the end we
> had to *pay money* for the Council to come and take it away... grr!!
Sometimes if it's "free for the taking" people won't take it, next time
put a sign on it saying "£20", then they think they're stealing something
of value. ;-)
Jim
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Jim Henderson wrote:
> Sometimes if it's "free for the taking" people won't take it, next time
> put a sign on it saying "£20", then they think they're stealing something
> of value. ;-)
Humans are truly perverse...
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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And lo on Mon, 09 Jun 2008 15:50:14 +0100, Invisible <voi### [at] devnull> did
spake, saying:
>>>> Out of pure curiosity did the suppliers of your new oven take the old
>>>> one away for free?
>>>
>>> Actually no.
>> Was it pure gas or did it have an electric hob?
>
> Nope, just gas.
>
> [Did have an electric timer and temperature meter - but both of these
> elements were Fraggle-rocked.]
Ah yep those don't count, if it did have an electric hob it'd be
classified as WEEE and they would have had to take it away with them in
exchange for the new one.
>>> It's quite irritating really. I've been hearing all kinds of stories
>>> on the news about people stealing metal. (Not to be confused with
>>> "steeling metal".) Apparently one house had their roof stolen (?!),
>>> and a church had their bell stolen. But *we* leave an old oven and a
>>> sink sitting on our front lawn for a week or two and does anybody
>>> steal it? NO. In the end we had to *pay money* for the Council to come
>>> and take it away... grr!!
>> Too hard to dismantle into useable parts for melting down.
>
> Er... a *sink* needs dismantling?? It's a sheet of metal! o_O
Not enough metal perhaps to be worth 'stealing'
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
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Invisible wrote:
> Jim Henderson wrote:
>
>> Sometimes if it's "free for the taking" people won't take it, next
>> time put a sign on it saying "£20", then they think they're stealing
>> something of value. ;-)
>
> Humans are truly perverse...
>
Reminds me of the time I tried to get rid of an old VW Caravette. I left
it in a car park in the Lake District with the keys in and all the doors
unlocked. Result: it was still there two months later untouched and not
even ticketed by the council. I had to pay someone £15 to take it away.
John
--
I will be brief but not nearly so brief as Salvador Dali, who gave the
world's shortest speech. He said, "I will be so brief I am already
finished," then he sat down.
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On Mon, 09 Jun 2008 16:50:46 +0100, Invisible wrote:
> Jim Henderson wrote:
>
>> Sometimes if it's "free for the taking" people won't take it, next time
>> put a sign on it saying "£20", then they think they're stealing
>> something of value. ;-)
>
> Humans are truly perverse...
Indeed we are. ;-)
Jim
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>>> Was it pure gas or did it have an electric hob?
>>
>> Nope, just gas.
>>
>> [Did have an electric timer and temperature meter - but both of these
>> elements were Fraggle-rocked.]
>
> Ah yep those don't count, if it did have an electric hob it'd be
> classified as WEEE and they would have had to take it away with them in
> exchange for the new one.
Mmm, interesting. So it has to be more than 7% electronic before it's WEEE?
>> Er... a *sink* needs dismantling?? It's a sheet of metal! o_O
>
> Not enough metal perhaps to be worth 'stealing'
Well whatever. It's light, it's small enough for one person to carry,
you wouldn't need to plan ahead at all. I would have thought it would be
quite easy to remove. (They stole somebody's ROOF for goodness sake! How
much forward planning would that require?)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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And lo on Mon, 09 Jun 2008 16:50:46 +0100, Invisible <voi### [at] devnull> did
spake, saying:
> Jim Henderson wrote:
>
>> Sometimes if it's "free for the taking" people won't take it, next time
>> put a sign on it saying "£20", then they think they're stealing
>> something of value. ;-)
>
> Humans are truly perverse...
>
Indeed you are. ;-)
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
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And lo on Tue, 10 Jun 2008 08:54:33 +0100, Invisible <voi### [at] devnull> did
spake, saying:
>>>> Was it pure gas or did it have an electric hob?
>>>
>>> Nope, just gas.
>>>
>>> [Did have an electric timer and temperature meter - but both of these
>>> elements were Fraggle-rocked.]
>> Ah yep those don't count, if it did have an electric hob it'd be
>> classified as WEEE and they would have had to take it away with them in
>> exchange for the new one.
>
> Mmm, interesting. So it has to be more than 7% electronic before it's
> WEEE?
IIRC it's more to do with main functionality, if its main function (or one
of them) is electrical/electronic then it's WEEE.
>>> Er... a *sink* needs dismantling?? It's a sheet of metal! o_O
>> Not enough metal perhaps to be worth 'stealing'
>
> Well whatever. It's light, it's small enough for one person to carry,
> you wouldn't need to plan ahead at all.
Easy if you want to sell it as a sink, but it's not small enough to be
easily melted down and sold as anonymous scrap
> I would have thought it would be quite easy to remove. (They stole
> somebody's ROOF for goodness sake! How much forward planning would that
> require?)
A ladder and some tools. We've had the lead flashing nicked off four units
overnight and another business some ingots, but none of their machinery or
other items such as power tools etc.
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
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On Tue, 10 Jun 2008 08:58:43 +0100, "Phil Cook"
<phi### [at] nospamrocainfreeservecouk> wrote:
>And lo on Mon, 09 Jun 2008 16:50:46 +0100, Invisible <voi### [at] devnull> did
>spake, saying:
>
>> Jim Henderson wrote:
>>
>>> Sometimes if it's "free for the taking" people won't take it, next time
>>> put a sign on it saying "£20", then they think they're stealing
>>> something of value. ;-)
>>
>> Humans are truly perverse...
>>
>
>Indeed you are. ;-)
>
Keep looking up to us, sapiens. :p
--
Regards
Stephen
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