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Author Topic: Why Does A Wet Cloth Make Opening A Jar Easier ?  (Read 7829 times)

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« on: 24/08/2008 19:50:38 »
Dear Jar Openerologists,

In your study of the science that delves into the nature of ' Jar Opening' Have ewe discovered the reason behind this phenomenon ?






=





BUT !!







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Why's that then ?



Neil
Opener Of Jars Enquirer !









 

Offline JimBob

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #1 on: 24/08/2008 22:38:51 »
Olive got is a guess - it's your imagination. I find it more difficult when wet.
 

Offline RD

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #2 on: 24/08/2008 23:05:07 »
A bone-dry chamois leather slides over glass much easier than a slightly damp one:
a damp chamois leather sticks, making that squeaky sound.

So dampness can increase friction.

I suspect this is due to the surface tension of water: van der Waals forces.

Quote
The ability of geckos to climb on sheer surfaces has been attributed to van der Waals force.
A recent study suggests that water molecules of roughly monolayer thickness (present on all surfaces) also play a role
.
http://en.wikipedia.org/wiki/Van_der_Waals_forces
 

Offline JnA

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #3 on: 25/08/2008 01:06:30 »
there's a fraction too much friction
 

Offline Karen W.

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #4 on: 25/08/2008 07:21:42 »
I have never tried a wet towel or rag. I must try it.. I always hit the center of the lid with my palm, it breaks the suction and the jar then pops open when turned!
 

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #5 on: 25/08/2008 14:57:51 »
Olive got is a guess - it's your imagination. I find it more difficult when wet.

Thank Ewe Jimmy Boy...I used to try opening jars as soon as I stepped out of the shower too....I even formed a club...'The Just Stepped Out Shower Jar Openers'.......we used to meet, have a shower and then open jars !!...we even had day trips to waterfalls and especially loved rainy days where we would congregate atop Welsh hills during a storm and open jars !.....oh...those were the days !!....hmmmmmmmm..I was the only member though !! *le sigh*

« Last Edit: 25/08/2008 14:59:51 by neilep »
 

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #6 on: 25/08/2008 14:59:37 »
A bone-dry chamois leather slides over glass much easier than a slightly damp one:
a damp chamois leather sticks, making that squeaky sound.

So dampness can increase friction.

I suspect this is due to the surface tension of water: van der Waals forces.

Quote
The ability of geckos to climb on sheer surfaces has been attributed to van der Waals force.
A recent study suggests that water molecules of roughly monolayer thickness (present on all surfaces) also play a role
.
http://en.wikipedia.org/wiki/Van_der_Waals_forces

Excellantay !!...weeth all these answers ewe are spoiling me Mr RD Sir.

Thank ewe very much...that is very interesting stuff...
 

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #7 on: 25/08/2008 15:00:45 »
there's a fraction too much friction

brrrrrr...too much friction makes ewe sore !  ;D...erhmm...when it comes to opening jars that is !!
 

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #8 on: 25/08/2008 15:02:21 »
I have never tried a wet towel or rag. I must try it.. I always hit the center of the lid with my palm, it breaks the suction and the jar then pops open when turned!

Yes, yes..I often hit it too or invert the jar and whack it gently on a hard surface !...but sometimes, there's nothing like wringing the neck of a jam jar with a wet cloth !!.....*le sigh*...takes me back to my club days..*see above*
 

Offline Karen W.

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #9 on: 25/08/2008 15:05:29 »
LOL Thats quite the club Sir! LOL...
 

Offline rosalind dna

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #10 on: 25/08/2008 18:58:09 »
Neil have you ever tried levering the top of the lid with a small knife before removing it and turning then devouring it's contents if they are foody ones?
 

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #11 on: 25/08/2008 19:04:47 »
Neil have you ever tried levering the top of the lid with a small knife before removing it and turning then devouring it's contents if they are foody ones?

Hi Rosalind,

No, I've never tried that..but I will next time !  I do seem to be cosuming quite a lot recently !  Thank ewe for this useful tip.
 

Offline rosalind dna

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #12 on: 27/08/2008 15:21:31 »
Neil have you ever tried levering the top of the lid with a small knife before removing it and turning then devouring it's contents if they are foody ones?

Hi Rosalind,

No, I've never tried that..but I will next time !  I do seem to be cosuming quite a lot recently !  Thank ewe for this useful tip.

It's fine and next time that I need to open a jar if I remember
I'll take a photo to try to explain how I open jars and with
the wet cloths because I think that the damp for the pressure
helps to realise the Vacuum tightness.
 

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #13 on: 27/08/2008 17:37:17 »
Neil have you ever tried levering the top of the lid with a small knife before removing it and turning then devouring it's contents if they are foody ones?

Hi Rosalind,

No, I've never tried that..but I will next time !  I do seem to be cosuming quite a lot recently !  Thank ewe for this useful tip.

It's fine and next time that I need to open a jar if I remember
I'll take a photo to try to explain how I open jars and with
the wet cloths because I think that the damp for the pressure
helps to realise the Vacuum tightness.


This will be most helpful indeed..Thank Ewe Rosalind
 

blakestyger

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #14 on: 27/08/2008 20:19:44 »
Try holding the jar on its side over the sink and pouring hot water over the metal lid only. It expands faster than the glass which is a poorer conductor of heat and the lid can then be opened in the usual way
I've never failed with this. [^]
 

lyner

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #15 on: 27/08/2008 20:54:09 »
WD40 is good for some things. You could develop a taste for it with your marmalade.
 

Offline rosalind dna

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #16 on: 27/08/2008 20:55:28 »
WD40 is good for some things. You could develop a taste for it with your marmalade.

Sophie what is WD40 and I don't like Marmalade.
 

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #17 on: 27/08/2008 20:57:02 »
Try holding the jar on its side over the sink and pouring hot water over the metal lid only. It expands faster than the glass which is a poorer conductor of heat and the lid can then be opened in the usual way
I've never failed with this. [^]



This is a great tip. Thank ewe blakestyger  !..I will definitely try this. I always have an air of trepidation when whacking the lid so hard !!...and this way seems perfectly logical and , with your affirmation, a proven technique too !!

nice !!
 

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #18 on: 27/08/2008 20:59:23 »
WD40 is good for some things. You could develop a taste for it with your marmalade.


Marmalade and WD40 !!..I think C3PO or R2D2 may prefer that !!..oh what the hell..I'll give that a try too..I'll just open the fridge and let loose an almighty spray within !!

Wifey will be happy......in fact...it'll actually add some credibility to her  " cooking "

Thank Ewe sophiecentaur
 

Offline neilep

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #19 on: 27/08/2008 21:01:28 »
WD40 is good for some things. You could develop a taste for it with your marmalade.

Sophie what is WD40 and I don't like Marmalade.

I'll jump in here before sophie does...WD40 is an all penetrarting oil in a spray can...here's a wikipedia link here....  http://en.wikipedia.org/wiki/Wd40     it's rather good stuff for lots of things !!
 

blakestyger

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #20 on: 27/08/2008 21:26:15 »
I don't know if you're serious about WD40 - I suspect not as it could taint anything foody for yards around. Anyway, it is for usually parts that have corroded slightly - jar lids are just tight with a bit of added vacuum to make things difficult.
 

Offline JnA

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #21 on: 28/08/2008 03:22:37 »
maybe you need to be lifting some weights on that treadmill of yours and just open the jar with your muscles.


;)
 

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Why Does A Wet Cloth Make Opening A Jar Easier ?
« Reply #21 on: 28/08/2008 03:22:37 »

 

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