Best relative humidity for storing knives

Rover-Friskey

Rover-Friskey

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I keep my slip joint pocket knifes in a US General Tool Chest. The RH in the room is usually between 55-60%. Is that too high? Most of my knife blades are stainless, though some are high carbon and a few Damascus. Most have bone handles, others have Delrin, etc. A few wood. What is the idea %RH? I keep the blades, bolsters, and springs lightly coated with 3-in-1 oil, and am now starting to clean off the oil on some high carbon blades using 99% Isopropyl alcohol then applying Renaissance Wax. Should I use desiccants? VCI paper?
Thanks,
RF
 
In my arid home environment in the desert southwest of the U.S., I've generally not had many issues with corrosion as long as the daily RH is maybe 30% or lower imost of the time. When it goes much above 30-40% for any extended period (days or weeks), that's when I've sometimes noticed a sudden appearance of rust spotting on some of my knives. I tend to watch more for that in our summer monsoon season from mid-June through the end of September, when humidity levels rise.

I lived in central Texas for 20 years, before coming back home to New Mexico. When I was in Texas, I was more diligent about making sure all my knives were completely clean & dry, and then sealing them in clean, new Zip-Loc bags. Humidity levels outside usually ran from 60% during daytime to nearly 90-100% at nighttime, most of the year. I bagged all the unused knives & safe queens to protect them and also ran A/C most of the time in hotter months. I didn't worry as much about my EDC knives, since I handled them regularly and always cleaned them up after use.
 
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Rover-Friskey said:
I keep my slip joint pocket knifes in a US General Tool Chest. The RH in the room is usually between 55-60%. Is that too high? Most of my knife blades are stainless, though some are high carbon and a few Damascus. Most have bone handles, others have Delrin, etc. A few wood. What is the idea %RH? I keep the blades, bolsters, and springs lightly coated with 3-in-1 oil, and am now starting to clean off the oil on some high carbon blades using 99% Isopropyl alcohol then applying Renaissance Wax. Should I use desiccants? VCI paper?
Thanks,
RF
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At the least, I'd want to bring the relative humidity down below 55%. 50% would be a better all around RH to keep the room at.

I use and would recommend a Midea cube dehumidifier. Works great in my basement workshop / workout / storage area which otherwise would have too high an RH. They are very reasonably priced and work well.
 
Is there a room in the house with lower RH? Depending on HVAC and layout of home, RH may vary by room or floor.

Also, if house is too humid you are creating potential for mold, so dehumidifier or AC can help. Just have to make sure units don’t breed mold.
 
Rover-Friskey said:
I have 2 central ac units, keep room at around 75º. In southern Virginia, RH today is 97%.
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We can have high indoor humidity esp in summer. Got bad after new roof!

To take some of the load off the central AC, we installed “high grade” attic fan. (So far seems to help.) Also, we run dehumidifier in basement —and run AC a bit colder than you.

We also installed replacement windows on second floor to mitigate humidity. Still need to do first floor so can’t report definitively on windows.
 
I have 2 central ac units. keep house at ~75º. Today it is 90º & 97% here in southside Virginia. My basement is driest area at about 40% RH., as it is fed by one of the central ac units and it has a dehumidifier. House has basements plus 3 floors. May need to look at 1 or 2 more dehumidifiers, or lower ac to maybe....70º?. In meantime will get VCI papers and silica desiccants. Also, as i keep each knife in its own 1" x 1" x 4" Clear Box I can place a small desiccant pack and strip of VCI paper in each box in
addition to scattering desiccant in drawers. I have a mini Hygrometer/Thermometer in each drawer. They are quite inexpensive and accurate to ±1 % or degree F. ($7.99 for 6, or $1.33 each, on Amazon).
Thanks for all the ideas!
Rover-Frisky (Rover was my 1st dog, a Beagle, i got in 1956. Every morning I would get 2 small milk bone dog biscuits and we would go outside and sit on the back porch steps and eat our biscuits. I only ate part of mine as they were not exactly tasty, giving Rover the remainder. My 2nd dog was Frisky. We had moved into town and he followed me on my bicycle all over town. When left home for college he disappeared. I came home and spend an entire weekend looking for him with no success. My last dog was Stonewall, who i got for my oldest son who was 7 at the time. He was yet to be fully weaned and he cried in the basement until i went down and spent the night with him. He sucked my finger. And that is the story of my dogs! 🐕 🐕🐕)

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Knife RH.jpg
 
annr said:
We can have high indoor humidity esp in summer. Got bad after new roof!

To take some of the load off the central AC, we installed “high grade” attic fan. (So far seems to help.) Also, we run dehumidifier in basement —and run AC a bit colder than you.

We also installed replacement windows on second floor to mitigate humidity. Still need to do first floor so can’t report definitively on windows.
Click to expand...
that attic fan likely now depressurizes your house. meaning new hot and wet air from outside comes in the conditioned space of the home. unless you have enough gable and/or soffit vents to allow the cfm you're sucking out of the attic to be made up and not depressurize your home.

I pull these attic fans out all time to fix high humidity issues in depressurized houses. worst invention ever for high humid environments. you should also contact a quality roofing contractor that understands these things.......and make sure you have the right ventilation sqftage for your vented attic. also could have your ductwork checked for leakage. more supply leakage will depressurize the house. more return leaks pressurize it. I prefer a balanced or slight pressurized home. any good resent energy rater can do a duct test and smoke test and let you know the leakage and where to seal where the leaks are.

putting in new and better rated windows has changed the heat load on your home and in those rooms and reduced it. unless you had a hvac contractor do an acca manual j and d to check your ac system and ductworks ability to handle the load changes.

not enough details in your post to give exact answers and I haven't been there to do testing and see what's going on but making changes to a homes envelope systems will change other things more than many realize. good contractors with any knowledge of building science understand these things. Sadly many contractors don't understand these things and you end up doing lots of bandaids to fix issues that shouldn't be there.

on topic for op...

in the 40% to mid 50's% rh range should be fine.
 
jbmonkey said:
that attic fan likely now depressurizes your house. meaning new hot and wet air from outside comes in the conditioned space of the home. unless you have enough gable and/or soffit vents to allow the cfm you're sucking out of the attic to be made up and not depressurize your home.

I pull these attic fans out all time to fix high humidity issues in depressurized houses. worst invention ever for high humid environments. you should also contact a quality roofing contractor that understands these things.......and make sure you have the right ventilation sqftage for your vented attic. also could have your ductwork checked for leakage. more supply leakage will depressurize the house. more return leaks pressurize it. I prefer a balanced or slight pressurized home. any good resent energy rater can do a duct test and smoke test and let you know the leakage and where to seal where the leaks are.

putting in new and better rated windows has changed the heat load on your home and in those rooms and reduced it. unless you had a hvac contractor do an acca manual j and d to check your ac system and ductworks ability to handle the load changes.

not enough details in your post to give exact answers and I haven't been there to do testing and see what's going on but making changes to a homes envelope systems will change other things more than many realize. good contractors with any knowledge of building science understand these things. Sadly many contractors don't understand these things and you end up doing lots of bandaids to fix issues that shouldn't be there.

on topic for op...

in the 40% to mid 50's% rh range should be fine.
Click to expand...
Thanks for the comments. You could be correct...I've certainly taken bad advice as a homeowner. I agree it's impossible to change one variable in isolation. Finding a person to give a qualified answer is not so easy IME...

The fan is 10-speed, 0-10, and we don't run it when attic temp and humidity readings are good... Prior we got attic temps in the 100's w/ humidity in the 80-90's. I can see by the gauge that the attic humidity is lower. Is it the best option, working against us, work year-round? Don't know.

House is 65+ y/o and has 2 attic vents, one on either end. Outdoor temps can range from -15 to105 F (indoor humidity 15-70% untreated).

HVAC was replaced (including new ductwork) and tested simultaneously with attic fan install and window replacement. The windows needed either a full restoration or replacement. We got acoustic glass which I understand is not the norm. I guess we'll find out.
 
annr said:
Thanks for the comments. You could be correct...I've certainly taken bad advice as a homeowner. I agree it's impossible to change one variable in isolation. Finding a person to give a qualified answer is not so easy IME...

The fan is 10-speed, 0-10, and we don't run it when attic temp and humidity readings are good... Prior we got attic temps in the 100's w/ humidity in the 80-90's. I can see by the gauge that the attic humidity is lower. Is it the best option, working against us, work year-round? Don't know.

House is 65+ y/o and has 2 attic vents, one on either end. Outdoor temps can range from -15 to105 F (indoor humidity 15-70% untreated).

HVAC was replaced (including new ductwork) and tested simultaneously with attic fan install and window replacement. The windows needed either a full restoration or replacement. We got acoustic glass which I understand is not the norm. I guess we'll find out.
Click to expand...
being 65 plus old leaky envelope house, that helps on oversized hvac, if that even applies.

id focus on whether youre depressurizing the home or not. simple hvac unit on and attic fan on, using manometer to see pressures inside relative to outside in pascals will answer that quickly.
 
jbmonkey said:
being 65 plus old leaky envelope house, that helps on oversized hvac, if that even applies.

id focus on whether youre depressurizing the home or not. simple hvac unit on and attic fan on, using manometer to see pressures inside relative to outside in pascals will answer that quickly.
Click to expand...
Thanks. Would the HVAC guy be the best person to assess this?

Roofer, contractors, HVAC guy all kept mentioning that for an "old home," whatever they were installing was the way to go....and I have no clue.

Interesting about the leaky house. I taught a radiation oncologist who deliberately purchased an old, leaky home. He felt it was healthier not to have everything so tight. Again, this is not my area.
 
annr said:
Thanks. Would the HVAC guy be the best person to assess this?

Roofer, contractors, HVAC guy all kept mentioning that for an "old home," whatever they were installing was the way to go....and I have no clue.

Interesting about the leaky house. I taught a radiation oncologist who deliberately purchased an old, leaky home. He felt it was healthier not to have everything so tight. Again, this is not my area.
Click to expand...
Im moving this to a pm.....hope ya don't mind....I got thread way off topic and I know better.....
 
Rover-Friskey said:
I have 2 central ac units. keep house at ~75º. Today it is 90º & 97% here in southside Virginia. My basement is driest area at about 40% RH., as it is fed by one of the central ac units and it has a dehumidifier. House has basements plus 3 floors. May need to look at 1 or 2 more dehumidifiers, or lower ac to maybe....70º?. In meantime will get VCI papers and silica desiccants. Also, as i keep each knife in its own 1" x 1" x 4" Clear Box I can place a small desiccant pack and strip of VCI paper in each box in
addition to scattering desiccant in drawers. I have a mini Hygrometer/Thermometer in each drawer. They are quite inexpensive and accurate to ±1 % or degree F. ($7.99 for 6, or $1.33 each, on Amazon).
Thanks for all the ideas!
Rover-Frisky (Rover was my 1st dog, a Beagle, i got in 1956. Every morning I would get 2 small milk bone dog biscuits and we would go outside and sit on the back porch steps and eat our biscuits. I only ate part of mine as they were not exactly tasty, giving Rover the remainder. My 2nd dog was Frisky. We had moved into town and he followed me on my bicycle all over town. When left home for college he disappeared. I came home and spend an entire weekend looking for him with no success. My last dog was Stonewall, who i got for my oldest son who was 7 at the time. He was yet to be fully weaned and he cried in the basement until i went down and spent the night with him. He sucked my finger. And that is the story of my dogs! 🐕 🐕🐕)

View attachment 2905474
View attachment 2905476
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Thanks for nice pics. I had that same Case until I sharpened it up and someone else decided to "borrow" it.

Nice story about your dogs! I know another BF member who has a similar handle, their 2 doggies!

Please let us know how you make out with the things you try or any tricks you may discover.
 
IMG_0942.jpeg

Found the knife and you can see some of the stains. Asked user what caused this, and he said he did not dry it well after washing. Oh well.
 
Rover-Friskey said:
I keep my slip joint pocket knifes in a US General Tool Chest. The RH in the room is usually between 55-60%. Is that too high? Most of my knife blades are stainless, though some are high carbon and a few Damascus. Most have bone handles, others have Delrin, etc. A few wood. What is the idea %RH? I keep the blades, bolsters, and springs lightly coated with 3-in-1 oil, and am now starting to clean off the oil on some high carbon blades using 99% Isopropyl alcohol then applying Renaissance Wax. Should I use desiccants? VCI paper?
Thanks,
RF
Click to expand...
Buy camphor blocks on Ebay and put a couple in the tool chest. Machinists use them to protect precision tools.
 
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