Announcement

Collapse
No announcement yet.

Using a working fridge to store guns

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

    #61
    Originally posted by Ricekila View Post
    Living room --bottom #'s -- 42% humidity -



    Freezer -- 26%

    I suspect that this is a problem with the sensor in your hygrometer being out of it's measurement capabilities, rather than the humidity being actually 26% in your freezer. I own an actual wet-bulb hygrometer, but do not own a walk-in refrigerator I could test it out in, and my wet-bulb hygrometer (actually, most hygrometers for that measure) just don't work below the freezing point of water anyway.

    Comment


      #62
      The point --- its less humid in cooler / cold air ---

      Question my cheap-ass-ed hydrometer ?--- good day sir ! -- LOL
      NRA Instructor / RSO & NRA Life Member / S.A.F.E. Armorer / 03-FFL / Moist Nugget gun nut / Ammosexual / And a right wing Republican Jew with guns

      Comment


        #63
        Originally posted by rlitman View Post

        And you know enough about refrigeration to get yourself into trouble. Yes, the evaporator removes SOME water from the air. And where LI Ammo and you are correct, is that the ABSOLUTE HUMIDITY is lowered by the evaporator. But that's not the whole story, and is very misleading. So, since it seems this needs to be spelled out slowly, read on, and maybe you'll learn something.

        Absolute humidity is a measure of the partial pressure of water vapor in the air, or stated another way, the total amount of water in the air. Unfortunately, absolute humidity is NOT relevant to the question of corrosion (it is however believed to be the major factor with regards to the triboelectric effect, but that's not important for firearm storage; talk to me if you run a data center or some other facility sensitive to static electricity).

        What I'm focusing on instead is RELATIVE HUMIDITY. Relative humidity is a measure of the humidity, on a scale based from zero water to saturation. The important distinction here is that cold air has a lower saturation point, or put another way, cold air is not able to hold as much water.

        The evaporator chills the air to the point that water condenses directly on it. AT THE POINT THAT WATER IS CONDENSING ON THE EVAPORATOR, THE RELATIVE HUMIDITY IS ONE HUNDRED PERCENT. How is this so? Well, we started with warm air that was maybe 50% humidity, but as we started to cool it (before there was any concentration), while the absolute humidity stayed the same, the relative humidity increased as the temperature decreased. This is because the amount of water that air is able to hold decreases with decreasing temperature.

        Consulting this psychometric chart, if you start at 70F and a very dry 10% RH, by the time you cool the air down to 47F, you will have reached saturation at 100% RH (that is the "wet bulb" temperature"). Since the refrigerator is colder than that, it will of course condense most of the water out of that air, but the relative humidity will stay quite high within the refrigerator. Now if you were to take a bag of air at 100% RH chilled to 37F in your refrigerator and warm it up in your room, it would already be dropping below 10% RH by the time it passes 54F.

        So, yes, the evaporator removes almost all the water from the air by the time it is chilled to refrigerator temperatures, but as I'm pointing out, the relative humidity is raised, and my understanding is that relative humidity has a greater effect on the rate of corrosion than absolute humidity.

        corrosion_prevention_chart.jpg

        As for the "almost" in my previous paragraph, that's an important distinction. As I said in a previous post, refrigerator manufacturers want to keep the humidity levels in the fridge as high as possible. There WILL be condensation, but all efforts are taken to minimize it. The best method (and what most refrigerators resort to) is to rapidly circulate the freezer air over the coil, and control the entrance of air from the refrigerator compartment, to prevent the coil from condensing too much. Instead, the refrigerator is cooled more through limited insulation between the compartments. This moves refrigerator air over a much warmer surface than the coil, which reduces condensation.

        For comfort air conditioning (Florida weather), a different tactic is used. There, you want to maximize dehumidification (aka "latent" cooling), by slowing the airflow over the super cooled coil, condensing as much as possible. Dehumidifiers work this way too.

        Now what this all means for firearms storage is a good question, that I cannot confidently answer, because humidity is not the only factor here. Corrosion is a chemical process, and chemical processes are accelerated with increasing temperature. Several studies I have read also state that stress and crevice corrosion cracking are less likely to occur at low temperatures, so perhaps the cold is protective, but the condensation formed on cold metal surfaces removed from the fridge can easily be devastating, and I just wouldn't suggest risking it.
        I never said I would do it.
        For me I would be concerned about the condensation that will form when you remove the firearms from the fridge. You can wipe down the outside but what will you do about areas you can't get to?

        You have some inaccurate statements about how the refrigerator side is cooled but it really doesn't matter and I guess you have never seen the higher end units with two separate systems.

        Comment


          #64
          Five pages on refrigerators used as gun storage? I think I'd rather throw my guns in a lake rather than keep reading!

          Just buy a safe! ...or a gun cabinet for that matter! Get a goldenrod or a rechargeable desiccant. Every time you buy footwear or something else that comes with a desiccant pack, throw it in there (near the top).

          Comment


            #65
            I gots oodles of those little packs stored in pill containers --
            NRA Instructor / RSO & NRA Life Member / S.A.F.E. Armorer / 03-FFL / Moist Nugget gun nut / Ammosexual / And a right wing Republican Jew with guns

            Comment


              #66
              Originally posted by Range Time View Post
              Five pages on refrigerators used as gun storage?
              that how you know you are reading the internet.

              Comment


                #67
                Originally posted by Shotgun View Post
                ...You have some inaccurate statements about how the refrigerator side is cooled but it really doesn't matter and I guess you have never seen the higher end units with two separate systems.
                I've seen them, and am versed in Sub Zero. I was just speaking in generalities. Yes, with a separate compressor, you can optimize sensible cooling better.
                Funny thing about "higher end" units. EVERY SINGLE person (about 10 I can think of off the top of my head) that I know who has owned a Sub Zero has been through at least 2 compressor replacements per decade of use (one has been through 5 IIRC)..

                Originally posted by Range Time View Post
                Five pages on refrigerators used as gun storage? I think I'd rather throw my guns in a lake rather than keep reading!

                Just buy a safe! ...or a gun cabinet for that matter! Get a goldenrod or a rechargeable desiccant. Every time you buy footwear or something else that comes with a desiccant pack, throw it in there (near the top).
                I have a goldenrod in one safe. That's my favorite choice. But in another safe without power, I made a desiccant pack using beads I bought in bulk sewn into a bag I made. But I also treat my gun socks and bags with VCI oil (which will prevent corrosion in far harsher environments).

                The goldenrod ensures that even with changes in humidity and temperature around the safe, the guns inside will remain above the dew point, so they will never see any condensation. Too low a humidity is actually harmful to both wood and many polymers. Nylon, for instance, will dry out and get brittle with too low moisture.

                Comment


                  #68
                  Originally posted by rlitman View Post

                  I've seen them, and am versed in Sub Zero. I was just speaking in generalities. Yes, with a separate compressor, you can optimize sensible cooling better.
                  Funny thing about "higher end" units. EVERY SINGLE person (about 10 I can think of off the top of my head) that I know who has owned a Sub Zero has been through at least 2 compressor replacements per decade of use (one has been through 5 IIRC)..



                  I have a goldenrod in one safe. That's my favorite choice. But in another safe without power, I made a desiccant pack using beads I bought in bulk sewn into a bag I made. But I also treat my gun socks and bags with VCI oil (which will prevent corrosion in far harsher environments).

                  The goldenrod ensures that even with changes in humidity and temperature around the safe, the guns inside will remain above the dew point, so they will never see any condensation. Too low a humidity is actually harmful to both wood and many polymers. Nylon, for instance, will dry out and get brittle with too low moisture.
                  ​​​​​​
                  So what's optimal? 35-40%?

                  Comment


                    #69
                    Originally posted by Range Time View Post

                    ​​​​​​
                    So what's optimal? 35-40%?
                    Pretty much, yeah. 55% is usually the magic number for corrosion. Below that is safe, above that is not. Mold formation is greatly inhibited below 60% too, so that's a bonus (the same goes for fungus, which can be awful on optics that are stored in high humidity). Staying above 35% is optimal for wood. Water acts as a plasticizer in nylon (polyimides), and other polar plastics as well. It will reach an equilibrium with its environment over time, where more moisture will make the plastic more impact resistant, though softer (it also swells).

                    So, I'd say that 35%-50% is ideal. 15% and 60% are touching on the red zone for long-term firearms storage. But then again, there's always the cosmoline option, or if you can prevent airflow, VCI will inhibit corrosion at any humidity level. I see some literature that VCI can inhibit mold and fungus as well.
                    Last edited by rlitman; 05-04-2019, 10:38 PM.

                    Comment

                    Working...
                    X