• makeshiftreaper@lemmy.world
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    4 months ago

    I don’t know where this is but it doesn’t sound impossible to me. A quick Google shows that the FDA recommends 160 F for casseroles and that in direct sunlight a car can hit 160 if the ambient temp is >105 F. I know mailboxes aren’t cars, but over a longer period in a smaller metal box, it seems like the math could check out

    • Badabinski@kbin.earth
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      4 months ago

      I live in Utah where it’s been sinfully hot and dry for the last week. I fully intend to test this theory. I just bought a high temp probe that should get here tomorrow. I will provide an update once the testing has been completed.

      • Badabinski@kbin.earth
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        4 months ago

        Alright, I have the sensor installed. It’s a bit cooler and more overcast today, but I’ll hopefully be able to get some good data.

        A graph from Home Assistant showing the current temperature of the mailbox.

        • makeshiftreaper@lemmy.world
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          4 months ago

          I don’t know if this could inadvertently dox you but I’d be curious to see an hourly outside temperature too to see how much hotter a mailbox gets than outside. Based off your first graph here I’m wondering if cars having glass windows makes a greenhouse effect that would make a car hotter than a mailbox, everything else equal?

          • Badabinski@kbin.earth
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            4 months ago

            Seems like a worthwhile thing to do! I’m not worried about doxxing, since someone would have to go to pretty extreme measures to correlate with the exact climate where I’m at. I installed the sensor after the hottest time of day had already passed, but here’s what it looked like:

            A graph showing the outside temperature versus the temperature in the mailbox.

            I’m pretty sure the spikes in the mailbox temperature were due to cloud cover.

            • makeshiftreaper@lemmy.world
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              4 months ago

              In my opinion this pretty conclusively proves that you can’t make a mailbox lasagna. This is the graph I looked but for my previous statement:

              A graph showing the temperature the inside of a car can reach in the sun

              And it shows that a car can hit 130-140 at temps around what you posted. Which is so much wildly higher than what you posted I do have to assume cars have some sort of greenhouse effect going that mailboxes don’t

              Finally when you consider how much of the total volume of a mailbox a lasagna covers, I have to imagine that’ll slow heating down even more! Great work!

              • Badabinski@kbin.earth
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                4 months ago

                As a follow-up, I have a new record temperature. Thanks, West Coast heat dome!

                altr

                Here’s with the ambient air temperature:

                altr

                • makeshiftreaper@lemmy.world
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                  4 months ago

                  Damn. Even with the crazy high heat you’re basically parking the food right in the danger zone for bacteria growth. Mailbox lasagna: busted

        • rhandyrhoads@lemmy.world
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          4 months ago

          By the way, just a quick tip, if you haven’t already maybe try airgapping the sensor from the metal with some foam so you’re measuring the air itself.

          • Badabinski@kbin.earth
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            4 months ago

            I have it positioned right now so that the probe tip isn’t touching any metal, but I’ll probably add a bit of foam. I have some incredibly irritating foam packing peanuts that would probably work well. I’ll go do that now.

            EDIT: here it is, in all its gloriously crappy, uh, glory:

            a picture of a temperature probe poking into the inside of a mailbox. A Styrofoam packing peanut with a hole in it has been put over the probe to stop it from touching the walls of the mailbox.