# How to make a glass out of a bottle

using only
a bottle and a rope and a water soure

using only
a bottle and a rope and a water soure

Do you mean looking glass?

no a class for contaning liquides

What's the bottle made out of? Can the water "source" be steam? Or ice, for that matter? Can I close the bottle? Actually, can I open it? How much rope is there? Is the rope thin enough to fit through the opening of the bottle, assuming there's one-and-only-one opening in the bottle? If the bottle isn't already made out of glass, I think the answer is pretty definitively "no", unless there are some other ingredients (like sand at least). Is there a time limit for how long it takes, or can it take 1000 years and still be acceptable?

DaveE

lisab
Staff Emeritus
Gold Member
no a class for contaning liquides

...but the bottle already will contain liquid...why go to so much trouble?

Besides, topologically speaking they already are the same shape .

a glass bottle like a wine bottle
with a narrow opening

we need to convert it to a drinking cup
using a rope (as long as you want) and a water source

this proccess took at most 10 minutes

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If I can use alcool too, I tie the rope around the bottle and soak it with alcool. Then I put water in the bottle until the level of the rope.
Igniting the rope the outside of the bottle will expand. The water dissipates the heat maintaining the form in the inside of the bottle.
The stress will cut the bottle neatly, making a drinking glass.

If I can use alcool too, I tie the rope around the bottle and soak it with alcool. Then I put water in the bottle until the level of the rope.
Igniting the rope the outside of the bottle will expand. The water dissipates the heat maintaining the form in the inside of the bottle.
The stress will cut the bottle neatly, making a drinking glass.

Well, you don't actually need alcohol for that, since there aren't any details whatsoever about the water source and so forth. You put cold water on the inside of the bottle, wrap the rope around the bottle appropriately, and subject it to intensely hot steam (a water source). Again, the water INSIDE the bottle acts as a heat sink (not to mention the rope around the outside, which can act as a shield), and helps to cool the glass in the bottle that's touching the water. Meanwhile (since glass isn't a good conductor) the glass that's exposed to the steam directly expands and breaks.

You could probably even do it with NO rope, and just using water, since the difference in temperature between nearly-freezing water and boiling water is (I believe) sufficient to break glass.

DaveE

Well, you don't actually need alcohol for that, since there aren't any details whatsoever about the water source and so forth. You put cold water on the inside of the bottle, wrap the rope around the bottle appropriately, and subject it to intensely hot steam (a water source). Again, the water INSIDE the bottle acts as a heat sink (not to mention the rope around the outside, which can act as a shield), and helps to cool the glass in the bottle that's touching the water. Meanwhile (since glass isn't a good conductor) the glass that's exposed to the steam directly expands and breaks.

You could probably even do it with NO rope, and just using water, since the difference in temperature between nearly-freezing water and boiling water is (I believe) sufficient to break glass.

DaveE

Well, I have done the trick with alcool and a string (not a rope) and I know it works.

you are correct that its a string

this srting is a thin rope substance(like hemp rope)

no alcohol
and we have only cold water

in the end we get get a clean cut of the bottle

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1st clue:
the water splits the glass

DaveC426913
Gold Member
Soak the string. Tie it tightly around the bottle. Let it dry? It will shrink.

I just doubt that you'll avoid shattering the bottle.

And I assume we don't have to concern ourselves with a razor-sharp edge?

you are close to the truth but you are not correct

we get a lean cut

DaveC426913
Gold Member
you are close to the truth but you are not correct
we get a lean cut
Then you've got to use the string as a saw. I'm just not sure how.

you tie a loop around the bottle at the place you want to cut it
and two people move it back and forward thus creating local heat from the friktion on the place of the rope

then we pore water on that bottle
and because of the heat differences the glass splits clean

I've noticed a lot of the brain teasers here aren't really brain teasers or riddles but more of "what would McGyver do" kind of questions.