How could I get a stopper out of a flask if it won't just fall out?

[flarn2006]

Recently I accidentally stoppered a flask with a stopper that was too small. It still plugged the top of the flask, but it was in real deep (no, I don't mean that... ) I managed to get it out (it was hard) but it came close to actually falling into the flask. Had it actually fallen in, it wouldn't come out if I just turned it upside down. How would I get it out? It's a 500ml filtering flask in case it matters. The stopper it came with (used for the Büchner funnel) did not have its size labeled, but the one I tried to use (that was too small) was a #7 stopper.

[Arthur Dent]

My first idea would be to find out what material is the stopper made of, and find a solvent that would "attack" the stopper, if it's neoprene, maybe some methyl ethyl ketone, or toluene would soften it enough to cut away its edges with an xacto blade attached to a dowel and it would just fall out when turned upside down. If it's cork, maybe just a bit of conc. HCl. If it's teflon... well, you got me there! LOL

 

- Robert

[Greippi]

Also depends on what's in the flask and how tightly it's wedged in there. If it would be safe to do (i.e. if there was just a bit of water or nothing in there), and if the stopper isn't wedged in too tightly, might be an idea to gently heat the flask, thus slightly increasing gas pressure inside, and loosening the stopper a little so it might just fall out when you upend it.

[CharonY]

For a filtering flask it ain't that easy, but I had problems with small stoppers in test tubes. I used a piece of folded cloth to guide the stopper to the opening of the inverted tube. Then pulled it out by tugging at that cloth.

[DJBruce]

A method you could use to get the stopper out of the flask similar to the one suggested by CharonY is shown in this video:

 

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I have never done used it to remove a stopper, but I have done it with a wine bottle as in the video, and it worked well, and looks really cool. I would assume it would work equally well for removing a stopper as its basically the same as a wine cork.

[Darthoper]

Wow that is carzy, what a great idea^