Kitchen Physics: How to unstick metal pot lid from wooden salad bowl

Question

So this isn't really a home-improvement question but I think the people here have the skills to answer it. If there's a different site you'd recommend asking, please let me know and I'd be happy to move it there.

My wife and I got a salad bowl that was hand-made by my uncle as a wedding present. It has sides that are perpendicular to the bottom of the bowl. At some point a pot lid was placed on the bottom. Nobody noticed that it fit around the bottom of the bowl well. In fact, it fit a little too well. We just noticed that the lid is firmly stuck to the bowl.

Becuase it was a hand-made family wedding gift, I want to minimize any possible damage to the wood bowl. But the solutions I can think of to separate them are contradictory. Our apartment has gone from the usual summer 75 F to a comfortable fall 70F. We don't have a thermostat or control over our heater (this is normal in our city). So I assume the metal getting colder and contracting doesn't help things. But it also means it's less humid so the wood should be swelling less. I could put it in the driest location I can think of, but that would be even colder, causing the pot lid to contract more. I could apply heat to the lid, but most ways I have access to involve steam or hot water, which would swell up the wood. Then there's trying to add oil or soap to the place where it meets, and even if I could get those between, the slipperiness interferes with anyone trying to grip them and pull them apart.

What would you suggest for getting this metal lid unstuck from around the outside of a wooden bowl?

Answer 1

Heat is the right thing here, even if it's steam. The lid will expand more than the wood will. I suggest putting a saucepan with water on the stove, and then placing the lidbowl on top of that. Heating the saucepan and water will directly heat the lid, and limit the amount of heat and steam on the bowl.

Answer 2

The answers aside from this one are worth reading, but I actually figured one out after posting: a hair dryer. That was our source of dry heat.

The metal lid did have a lip around it, so I set up a couple solid chairs next to each other, and put the stuck bowl/lid in between them such that it was being held up by the lid's edge, the bowl just being pulled down by gravity. Then I heated up the metal lid with the hair dryer. Once it was nice and warm, I took the bowl, lifted it slightly, and banged it downwards so that the chairs caught the edge of the lid while not impeding the bowl. Took a couple tries, but the thing came free.

Thanks all for indulging and making more suggestions! Hopefully this helps someone else in a similar situation.

Answer 3

It's unlikely that there's a huge amount of friction between the bowl and the smooth lid. Your primary hurdle is vacuum (more intuitively, atmospheric pressure).

With a helper holding the bowl firmly, tap downward on a block of soft wood or plastic that's resting on the edge of the lid. Work gently around the entire circumference. You should see incremental movement. Be patient, as air will need to slip past the wood-metal joint to fill the void inside.

It may take a few laps, but it'll come off.