gun safe humidity?

[Shadow 7D]

Consider getting a large bag of silica (crystal) kitty litter
you can recharge it by baking at 200 during the humid times
and, it will slowly release during very low times to keep it a little higher

too dry, too much of a swing can damage wood, but 0% is a lovely number for metal.

 

[JohnBT]

"before I sealed those doors during that very humid summer period, the RH inside my gunsafes was out of control"

High RH doesn't hurt a thing as long as the GR is free to do its job. I tossed the digital meter after a couple of years because the RH stayed in the 55% to 80% range and the guns were fine. Still are.

It just sounds to me like you're making more work for yourself by not using the GR according to the directions.

It's stays so humid around here that right now the outside temp is 30*F with 85% humidity. It's sunny and clear and headed for 65*F, a great day for our annual range trip.

John

 

[Bo]

When my safe was installed, the guy put a strip of stainless, about an inch wide and maybe 1/16 of an inch thick, under each side. He said, you don't need much space to get air underneath it. Direct contact causes rust. Also, the less space, the less chance of some one getting a pry bar or whatever under it. It's also bolted to the floor with 4 9/16 bolts.

 

[GBExpat]

John, I am glad to hear that your gunsafe contents are safe (no pun) from moisture/corrosion issues while enduring such high RH periods.

I was satisfied with my "standard" setup of GR-type heaters only and unsealed gunsafe doors ... until I was not.

During that wet summer when I only had GR-type heaters deployed (my setup for several years by that time) I did find the beginnings of rust on two of my rifles ... the in-safe hygrometers were displaying RHs in the upper 60s (basement RH low 70s). My first attempt at corrective measures was to buy the desiccant units. They knocked down the RH, some, but maxed out fast, needing recharge every few days, IIRC ... so I bought a 2nd set so that one could be recharging.

Then I stopped and turned up the gain on my brain and thought thru the issue. I realized that the additional moisture-laden air was being drawn in thru the unsealed doors (via the convection current created by the GRs).

So, with a roll of foam strip that I had on-hand, I sealed one of the doors and continued monitoring the environment in both gunsafes.

Within a few days, the sealed gunsafe RH was down to 50% and the speed of the dessicant loading was reduced by more than half. Due to this I sealed the door on my other gunsafe.

I also added a constantly-running small fan in each ... provides constant airflow & adds a bit of heat.

Since making these mods my gunsafe interiors never get over 55%RH and the temperature is always a couple of degrees above that of the air in the basement.

When I see the RH crossing the 50% threshold (sometime after I have to start deploying my portable dehumdifier in the basement), I start deploying the dessicant units until such time as the RH in the basement stays in the low 50s with no help.

With my setup, I can fire chlorate primered ammo in a rifle/pistol, put it in one of my gunsafes and clean it at a later time because I keep the RH low.

I hope that your annual range trip goes/went well!

Kim

 

[22-rimfire]

It is all about condensation and controlling that. If the interior safe temperature reaches the dew point, you will have condensation. A higher interior safe temp will increase the amount of moisture that the air can carry inside the safe and there will be no condensation. No condensation, no potential rust.

Using the small heater works inside a safe.

The alternative is to block the air from entering the safe and dealing with remaining moisture inside the safe with dessicants or keeping the relative temps (inside and outside) more or less equal. Hence no condensation.

The trick is to control where precisely the condensation occurs if it occurs.

I would suggest that you run a fan in your basement more or less constantly in order to minimize or eliminate any kind of thermal separation of air masses. Most of us think of the temperature we feel at waist to eye height. But often the temperature is a few degrees less at the floor level. Mixing the air masses eliminates this possible issue and potential problem with a gun safe.

 

[GBExpat]

Good info, thanks!

I would suggest that you run a fan in your basement more or less constantly in order to minimize or eliminate any kind of thermal separation of air masses.

Something that I have been doing since The Year of the Dehumidifier. It is a big, half-finished basement with many spaces/rooms so I make sure that there is a constant, if minor, air thru them all.



BTW, for those with older basements and no experience with portable dehumidifiers ...

We built this house in '87/'88. The half-bermed basement was remarkably dry (low RH) until a several years ago ... which is probably normal.

I knew that the basement was getting more humid each summer and then I ran into the gunsafe scenaorio mentioned earlier.

After that Scenario, one morning while shaking my head over some developing condition issues with assorted items in the basement, I decided to buy a portable dehumidifier.

I researched the subject & purchased a "71pt" Frigidaire. I deployed the unit with a 20" pedestal fan blowing for whole-basement air flow (as mentioned previously). It filled the water reservoir (2.5gal) every ~7-8 hours. I emptied it twice that day and left it running when I went to bed.

Next morning, I walked down to the basement and ... stopped ...

It smelled ... and felt ... fresher... down there. I don't know how to describe it better than that.

That dehumidifier was one of the best purchases I have made in a long time. I monitor the RH down there and when it starts climbing in Spring/Fall I use it daily as required.

My apologies, OP, just wanted to share that with everyone while we were on the subject ... sort of ...

 

[ColtPythonElite]

I have lived in dehumidifier dried basement houses since 1974. There is no way I would be without one. I have mine hosed into my sump pump well. I just set it and forget it. I leave it powered up year round. My basement humidity stays in the low 40's.

 

[brickeyee]

Condensation is a change of state, not a chemical reaction.

Dropping the temperature at constant humidity will eventually result in condensation when the object being cooled gets below the dew point of the air it is in.

Condensation on iron that is not otherwise protected quickly leads to the formation of rust.

 

[berettaprofessor]

Just came back from vacation and opened up the safe....35% humidity with two fully-charged dry packs. After the door was open for a couple of minutes it was 33%.....it's dry around here.

 

[GBExpat]

With the portable dehumidifier in my basement I always remind myself that while most of the RH Drop that I see is Moisture-Removal-Related, part of it is simply Temperature-Increase-Related.

Just something that I keep in mind.