sealed glass jars

How to Open a Canning Jar with Thermal Expansion

Thermal Expansion is One of The Best Way

All canning jar rings (and most lids) are made from a thin layer of metal. All matter tends to expand when heated.
• Metal just happens to expand more than glass.
• If you heat the metal lid and ring, it will expand and loosen its grip.
• For best results, try to only heat the metal and not the glass.

Heating the Metal Ring:

  1. Run Water on the Center of the Canning Jar Lid Only
    heating canning jar lid
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    Metal has a high rate of thermal conductivity which just means that it will heat pretty darn quickly and easily.

    All you have to do is heat the center of the lid and that heat will rapidly spread to the edges and the ring. Just hold the jar under running hot water and direct the flow at the center of the lid. (Not the glass)

    You can also run the hot water around the ring for good measure, then dry it off and give it a twist to see if it will open.

  2. Turn the Jar Upside Down into Warm Water
    jar upside down
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    This is a very common tip on the Internet and it does work in most situations. Also, it uses less water and is therefore less wasteful.

    However, there is one instance where this method won’t work well and that is when you are dealing with a refrigerated (or cold) jar.

    By turning the jar upside down, you put the cold contents up against the lid and that can prevent the lid from heating enough to make a difference.

    So if your jar is cold, skip this one.

    The idea is that by soaking the jar upside down, you not only heat the ring but also soak the goop underneath the ring that is causing the problem.

    Set the jar in the warm water for about 10 minutes and then give it a try

  3.  Heat the Ring With Hair Dryer
    heat with hair dryer
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    Another method for heating the ring is to use a hair dryer.

    The key with this method is to point the hair dryer at the lid rather than the glass of the jar.

    Again, this is so that the metal heats more than the glass.

    Just a minute or so of heat should do the trick

    Note: Hope above tricks do help you opening stuck canning jar lids

Better Lids We Recommended

mason jar lids

WHOOSH makes product for wide mouth Mason jar sizes, check it out

WHOOSH Fermentation Lids   –available for wide mouth Mason jars only.