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Q & A: plate stuck in galss dome

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Most recent answer: 12/10/2015
I have a glass cake platter with glass dome cover. My daughter put a plate slightly smaller than the cover with some hot freshly baked muffins on the platter and covered with the dome. Now the plate is stuck inside the dome cover, possibly because of a vacuum. Any ideas how I can get the plate to release without breaking it?
- Monica
Colorado Springs,

Great question! As you say, there may be a bit of a vacuum between the plate and the dome, created as hot moist air from the muffins cooled and some of the water vapor condensed to liquid. 

There are a couple of possibilities for unsticking the plate. You might put the dome upside down into a big bowl of hot water.  That should just slightly expand the dome. It would also help raise the air pressure inside a bit. Then you could try prying the plate up using a pointed knife, to break the likely vacuum. You could also put some ice cube on the plate, which would shrink it a bit. It's possible that just prying would work without the hot water or the ice cubes.

It's also possible that vacuum plays little role. Maybe there was something sticky on the plate that dried up sealing it to the dome. Then working your way around the edge with the knife might work best.

There are no guarantees either way,

Mike W.

(published on 12/08/2015)

Follow-Up #1: unsticking a plate

A slight modification on Mike W.'s solution: Lift the whole thing and place it upside up (not upside down) on a bowl full of ice and let the plate cool off and (hence) shrink a bit. You may hear a hiss sound of air rushing into the dome. Then just lift the dome as you would normally. This way you the cake will remain on the plate and you will be able to have your cake and it it too -- sorry! If you want a fancier (Clint Eastwoodish) solution, hang the dome (and the plate) with a string attached to the ceiling so that the plate is just a bit (1/8") off the table and let it sit overnight and watch the battle of gravity vs. air pressure (or sticky stuff).
- Mehran (age 65)
Arlington Heights, IL

Each method has its advantages.

Mike W.

(published on 12/10/2015)

Follow-up on this answer.