Fixing a Uno-vac stainless steel thermos

I’m new to the site, just re-read Every Tool’s a Hammer and thought that an army of makers might be able to help me with my problem.

This morning I dropped my stainless steel thermos in the parking lot and it landed right on its bottom edge. It is still intact and functional, of course, but now there is a dent on the bottom edge that causes it to wobble.

Before I take a hammer to it I was wondering if any of you might have some suggestions or advice. I don’t expect to fully restore it, just want to level it out a bit so it doesn’t wobble as much and whatever I do I don’t want to breach the vacuum. Any thoughts or should I just pound away?

Edit: here is my crude drawing of the ding

You may try some heat from a heat gun and see if it pops out. I would not suggest a torch.

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Unfortunately, I don’t have a heat gun on hand. Do you think a hair dryer might get it hot enough, or maybe a lighter?

epoxy to fill the void and level the bottom. automotive body filler even.

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It is worth a try.

I think see what you are saying, but I don’t think it will work in this particular case. The problem is that while the corner is dented in, the bottom is bulging out by the dent. I tried to take a picture but I is kinda difficult to capture.

I will bear that in mind if I need to fill in the corner to make it look nicer. Thanks!

Added a drawing of the problem to the original post since it is difficult to photograph.

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that’s good news, creased dents are tough to work with so being able to work it back in, as opposed to pulling out, is the best scenario. I would hammer it.

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Don’t know how big of a dent you’re working with, but I hammered one back in on the bottom my girlfriend’s stainless water bottle. No problems. It takes a pretty hard crease or a couple bends back and forth to break steel.

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Yeah, stainless steel will eventually work harden (it is austinitic) but I would be surprised if two cycles cause any microfractures that would breach the vacuum seal. And honestly, if it does, there’s a good chance that it’s already breached. Hammering it carefully would be my choice as well.

Most stainless steel needs to be heated to 1900°F and then water-quenched to anneal it, so there’s not much point taking a torch to it to try to undo any work hardening. :relaxed:

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