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Laurent Bourrou

How to remove a stuck stopper from a flask?

Darla  Follow

Here is an alternative that worked like a charm for me. I have a wide-mouth lab jar with a thick, ground glass stopper that stuck tight. None of the other methods worked; oil, heat, tapping, etc. I had an aerosol spray used to blow dust from computer keyboards/screens (it is not compressed air but a liquid that becomes a gas as it is released - i.e. the can gets very cold as you use it). A quick shot of cold gas directly on the stopper and it immediately shrank enough to easily come out of the jar.

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Frank Popa  Follow
This is another reason not to use glass stoppers with separatory funnels. If one isnt careful, pressure (from ether, CO2) can build up and the funnel may break. With a neoprene stopper one can feel the pressure as the neoprene stopper moves slightly.More
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Andy C  Follow

Another easy method is to get 2 other glass stoppers and tap them on both sides of the neck of the flask firmly, sometimes this will free it up immediately, other times you may need to have someone pulling the stopper while you hit the stoppers on the sides

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David Min  Follow

Is it a hollow glas stopper?

Sometimes, it helps to hold the flask at the body and hit the corner of the lab bench with the stopper. If that doesn't help, heat the neck of the flask carefully with a heat gun.

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Grace Smith  Follow
While @KlausWarzecha provided the working solution, I offer up my own adopted mantra for future reference. "Most human problems can be solved by an appropriate charge of high explosives."More
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Jerry Larson  Follow
No, it was a solid glass stopper. I tried the hitting method and it worked like a miracle.More
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Glen James  Follow
@86BCP2432T Im glad I could help! Btw, when silicone grease is not an option - and sometimes it isnt - teflon sleeves are a good alternative.More
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Jeffrey Martin  Follow
When I was younger I worked at a place which had a serious accident which could have been fatal. Someone tried to open a flask containing pet ether using a flame to heat the stuck ground glass joint holding the stopper. I tend to use the hitting method on a wooden surface, use many gentle taps and keep on turning the flask around. I never use a modern plastic type lab bench. This method deals with most stuck joints on flasks and bottles. Never use a flame on glassware to free a joint until you have removed all flammable solvent from the glassware.More
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Allan Emery  Follow

Is it a hollow glas stopper?

Sometimes, it helps to hold the flask at the body and hit the corner of the lab bench with the stopper. If that doesn't help, heat the neck of the flask carefully with a heat gun.

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Gregory Bloom-Salm  Follow
@86BCP2432T Im glad I could help! Btw, when silicone grease is not an option - and sometimes it isnt - teflon sleeves are a good alternative.More
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Fokhrul Islam  Follow
When I was younger I worked at a place which had a serious accident which could have been fatal. Someone tried to open a flask containing pet ether using a flame to heat the stuck ground glass joint holding the stopper. I tend to use the hitting method on a wooden surface, use many gentle taps and keep on turning the flask around. I never use a modern plastic type lab bench. This method deals with most stuck joints on flasks and bottles. Never use a flame on glassware to free a joint until you have removed all flammable solvent from the glassware.More
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Georg Uray  Follow
No, it was a solid glass stopper. I tried the hitting method and it worked like a miracle.More
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Jeff Iverson  Follow
While @KlausWarzecha provided the working solution, I offer up my own adopted mantra for future reference. "Most human problems can be solved by an appropriate charge of high explosives."More
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Chuck Smallman  Follow

Here is an alternative that worked like a charm for me. I have a wide-mouth lab jar with a thick, ground glass stopper that stuck tight. None of the other methods worked; oil, heat, tapping, etc. I had an aerosol spray used to blow dust from computer keyboards/screens (it is not compressed air but a liquid that becomes a gas as it is released - i.e. the can gets very cold as you use it). A quick shot of cold gas directly on the stopper and it immediately shrank enough to easily come out of the jar.

More

Upvote

VOTE

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Jane David  Follow
This is another reason not to use glass stoppers with separatory funnels. If one isnt careful, pressure (from ether, CO2) can build up and the funnel may break. With a neoprene stopper one can feel the pressure as the neoprene stopper moves slightly.More
Upvote

VOTE

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Brian Chilando  Follow

Another easy method is to get 2 other glass stoppers and tap them on both sides of the neck of the flask firmly, sometimes this will free it up immediately, other times you may need to have someone pulling the stopper while you hit the stoppers on the sides

More

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