Temperature and Humidity

[Michaelr]

For unseen reasons I am having to move my sword collection that is now displayed all around my living room to a finished room in the basement. The basement is dry but not heated. I will be installing a dehumidifier and a electric heater to control the environment. What are the recommendations as to the proper temperature and humidity? Since it will be a room approximately 14’ x20’ I can control the environment. Thank you in advance

MikeR

Below is what my living room looks like now

[charlie1]

Very nice display! Wish my wife would let me decorate the living room with my swords...

[tbonesullivan]

If this was guitars, I could help, but not with swords.  I would think the lower side for humidity would be best. You probably don't want it bone dry for the wooden artifacts, but maybe 40% humidity?  Temperature around 68 sounds good.

[Austus]

That's the best looking living room I've ever seen. I bet the unseen reason is a woman!    How about posting some of those swords in the "High Class Gunto" thread? 

[16k]

I love your display Michael.

 

As for the question, I don’t think a low temperature is necessarily a dangerous thing. The issues has more to do with humidity, so as long as you can take care of that issue, you should be fine. Just check regularly, just in case. Gunto are tough mothers.

[Michaelr]

Thank you all for the responses. I am glad you enjoyed the picture. No wife so that’s why I can display all my STUFF in the living room. I am in the process of selling my home and moving in with my 91 year old mother to help her out and I don’t think she would be open to a Japanese Living room but a nice space in the basement will do just fine. Austus I will have some time off near Christmas and would be more that happy to post more pictures of my swords

MikeR

[peterd]

Likes those Dragons. Is your tsuba up side down 

[SAS]

55% RH is what i have seen listed as what museums use for sword displays; lower wouldn't hurt the swords, but the koshirae might have issues. Higher RH and the swords may have accelerated rusting.

[Michaelr]

Lol I do not know Peter but I will have to check it when I get home. SAS thank you for the 55% RH. Do you think that if I can keep the RH at 55% the temperature isn’t too much of a factor? I currently check my blades twice a year but it is easier to remember when they are right in front of you.

MikeR

[SAS]

I think a constant humidity and temperature are both good, but the temperature needn't be in the comfort zone, i.e. expensive heating bill.

[Ken-Hawaii]

Nice collection & layout, Michael. And very good of you to care for your elderly mother. This article may make you feel better, https://www.collectioncare.org/relative-humidity-and-temperature but you should be checking your blades on a regular basis, more-frequently than you do now.

[16k]

Page isn’t showing for me, Ken.

[Ken-Hawaii]

You're right, JP, & that's strange. Let me try again: https://www.collectioncare.org/relative-humidity-and-temperature

[O-Midare]

 

 

 

https://www.collectioncare.org/relative-humidity-and-temperature

Page isn’t showing for me, Ken.

[Stephen]

Relative Humidity

Fluctuating relative humidity (RH) causes stress on materials. Rapid humidity fluctuation damages a wider range of museum objects than does temperature change. A change in RH causes dimensional alteration in hygroscopic materials (for example, wood, ivory, skin, and other organic materials), resulting in warping, splitting, and delamination of sensitive materials. Seasonal slow drifts are less harmful to structures and objects than abrupt changes. High RH (above 65%) can cause mold growth and metal corrosion. Low RH (below 25%) can cause embrittlement of hygroscopic materials such as leather and paper.

 

However, if you are in a wet or dry climate, it may not be possible to maintain the ideal RH level. Try to set your relative humidity level so that it is stable somewhere between 25% and 65%. Above 65% mold will grow, more rapidly as the RH rises. Below 25%, the materials may lose structurally important water. If you cannot achieve even these levels, achieve a reasonable level that does not fluctuate. If this level is above 65%, make sure you have good air circulation and regular inspections for mold growth.

 

Temperature

Temperature is the major factor in the speed at which "natural aging" occurs. Materials last longer at cooler temperatures. A rapid change in temperature, if the relative humidity is constant, may have damaging effects on stressed metals, stone, films, plastics or wax, materials from which many modern collections are made. High temperatures increase deterioration reaction rates and melt heat-susceptible materials. Store inherently unstable materials, like plastics and rubber, in cool temperatures and lower RH levels to decrease the rate at which they naturally deteriorate. Waxes and plastics are damaged by freezing, so should be kept cool, but not frozen. The Image Permanence Institute (not on the Internet yet) has developed resources for determining the longevity of film materials at specific temperatures and relative humidities.

[RichardP]

Very nice!

Any danger of flooding with the layout of your basement? (Would have to be a deluge to damage items mounted on the wall, but it would be terrible to have that tansu or anything else on the floor damaged...)

[ChrisW]

That's one heck of a man cave you have there already! Really digging the rifle at the top of the picture.

[Guido]

FWIW: the NBTHK keeps its blades and koshirae at 21° Centigrade and below 55% RH - at least those on display.

[SAS]

70 degrees  for us backward Yanks

[Michaelr]

WOW Thank you to all for all of the help. It is great to have a place like this to come and have such great help. Thanks to all that like my current living room. I will post some pictures when the new room gets set up. It will be a slow process but I will get it done. No need to worry about flooding as when the home was built it was surrounded with drains. (A family of plumbers ). I will install a weather station in the room and monitor it closely. I will also get into the habit of checking my blades more frequently.

 

MikeR

[Rivkin]

The answer is very convoluted.

First - no dust.

Second - Meiji and modern lacquer generally long term requires 50-60% humidity, held at a constant level. Exception can be made for super high quality items, but with the rest its dicy.

The old lacquer you have to look at each piece, but generally they are substantially more resilient.

Third - swords below 45% is generally safe long term.

 

Leather is problematic and generally requires conservation treatment.

 

If sterling silver does not tarnish with a year or two is a good sign the environment is good.

 

Kirill R.