I thought its important to discuss here this topic so we understand moisture content relative to humidity.
As we have different temperature and weather conditions in each state and to be more particular in each town we live in. As such we should understand and pay much attention to this very important aspect before we blame suppliers or the quality of wood or ourselves.
We all do read newspapers if not at least know how to check weather reports. Last time I checked the weather report they said it was going to be sunny and I water my yard and boom the rain was pouring cats and dogs on my lawn. I sometimes think the weather people can’t even say rightly when they will have their own breakfast. Just kidding guys – no offense meant to anyone.
Most Wood Workers, Luthiers, Woood Turners, Pen Turners, Hobbiest etc are aware that Seasonal changes in humidity can cause wood to shrink….. See Luthiers
Wood is hygroscopic- means it can absorb moisture from the air. This means the moisture content will fluctuate based on the humidity in the surrounding air. You can measure the humidity in the air where you store the wood with a hygrometer. I think it costs around $10 on eBay. I bought one and it works well. You will see from the image on the top right hand corner how much the temperature in my room which shows 81 degree Fahrenheit and that humidity level is 34 percent.
Pls look at the chart i gave below. In this chart it shows for example that when humidity is around 50 percent, the moisture content would be 9 percent. This is an average idea and though not approximate would help you have an idea of surrounding humidity and moisture level in the room.
Ok- Now you know that if humidity is higher, moisture content of the wood will also be higher. If you are planning to work on a wood thats been recently brought and transporting form one city to another or one state to another, it might take a little while for the wood to adjust to the moisture of the surrounding temperature. In other words the wood may take on more moisture or it may dry out.
You bought a piece of rosewood or ebony and they say that the moisture content is 10 percent air dried. If the wood you bought is exposed to higher moisture content at your location then the wood definitely will accumulate close to that moisture content.
You can also look at this example in this way also, if your wood is dried at 10 percent moisture content and is exposed to your room humidity at 25 percent (RH-Relative Humidity) the wood will dry to 5 percent Moisture Content based on the table I have given above. Its best we let the wood set there for a while to adjust to this change in this surrounding before we start working on it, I would say 3 – 4 weeks to be on the safe side. Also its best if its slim cut to put some weight on the edges so it don’t warp.
I had people who buy AAA rosewood Back & side sets from me and then talk about the set not being dried out. Well if you buy back & side set thats 4mm to 5mm thick and just make it lie down in a corner its gonna warp. You need to place some weight on the sets and let it adjust to room temperature.
This topic is indeed very complicated. I am not an expert here at all. I am just sharing the basic with you all. Bcos when it comes to wood there is lot of other factors that play on how the wood moves-
a) Width, length and thickness of the wood
b) If the wood is quarter cut or flat sawn
c) Moisture content of the wood at the time you receive it.
d) Humidity in your room or your house or place you store it.
e) Wood species also mater. Some wood species are tend to move less than others.
f) Density of the wood.
I do hope you will add on to your knowledge here. If I didn’t make sense then I sure didn’t. I was just trying to gather my thoughts here. 🙂 All suggestions and advise are welcome to help us grow our knowledge. I am happy when it comes too wood business, wood thoughts, wood sharing, wood ideas, wood creativeness – thats one field that big corporates companies have left us alone. I guess there’s no profit here maybe- Thanks a lot for all your business and your reading this article. I will do my best to serve you with quality products that are guaranteed. I thank eBay and all wood lovers for making my business a successes full one.