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How To Clean An Old Flask


Tis the season to sneak snifts of whiskey. Now is as good a time as any to dust off that old flask. But don't just pour, cap and pray. There's a good way to clean out the old flagon before you raise it to your whistle. Q&A site Stack Exchange provides some answers.

Illustration by Sean Gallagher.

"Somebody still uses you MS-DOS" Asks:

I found an old stainess steel flask that someone once gave me. I want to use it again to hold whiskey.

There doesn't seem to be any liquid inside, though it may have contained some just before the flask was forgotten.

How do I properly clean it so I can start using it again? Just hot water? No soap? Can I trust it? It was only used to hold whiskey.

Tobias Patton Answers:

If there's no evil smell emanating from the flask, just give it a good rinse with hot water. Otherwise, a 20 minutes soak in a dilute solution of bleach (around 1 tbs per gallon), followed by extensive rinsing with warm water should do the trick.

Wayfaring Stranger Answers:

Is the flask actually stainless, or merely something that's been plated bright and shiny? I'd go w vigorously shaking some sand around inside of it, to loosen any corrosion/crud deposits. Follow that with hot water and detergent, and brushing as possible. Finally, give it a soak in Vodka/Everclear. Check to see that the rinse solvent comes out clear and without chunks. For all you know, someone from the 1990's left Cream liqueur in there to evaporate.

Kristina Lopez Answers:

There are a number of flask and bottle brushes available online that will help with this task. I also found this set of instructions at ehow that recommends the use of boiling water and distilled white vinegar. Unlike most cleaning products, white vinegar will not leave a lingering scent in the flask.

Echilon Answers:

Steradent tablets are best for cleaning any type of flask in my experience.

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