I found a good deal on a large amount of red oak lumber this summer. It was 1″ thick and air dried for about 3 years. The only place I had to store it was upstairs in my pole barn. I am just getting around to using it and I am having trouble with it cracking. My concern is that it is to dry. I live in Michigan and my upstairs is not heated. My back work area is, but only when I plan on being out there. Now the questions:
1. How dry is to dry?
2. What moisture meter would you recommend?
3. If it is to dry, how would I bring it back up?
Replies
Interesting questions. I've never heard of doing something to "bring it back up" other than storing it in your shop for weeks (the longer the better). Painting the end grain with anchor seal or even latex would have helped and still maybe worth doing after sawing off the cracked ends. If red oak is quarter sawed, it is much more stable. I haven't bought a moisture meter yet, so I always weigh the wood and track weight loss over time until the weight stabilizes which is a good technique even if you have a moisture meter.
Let's start with the easy part. I use the General Tools MMD7NP and I like it. It is pinless, costs about $50, it's easy to use and you can set it for hardwood or softwood.
As for the other stuff, I don't claim to fully understand the physics of it, but I don't think it is possible to over dry wood without a kiln. Your barn loft might get to kiln temperatures (mine does) but the relative humidity is not regulated. The wood will not keep drying after it equalizes with the air around it. Michigan is not a terribly arid climate. Without a kiln, you are not likely to get below 10-15%.
Here is a link to a fairly informative article. (https://www.wagnermeters.com/moisture-meters/wood-info/acceptable-moisture-levels-wood/) The gist is for normal humidity homes you want wood to be dried to 6%-8%. So, I am going to posit that if your wood is dried to less than 3%, you will get an unacceptable amount of movement in your finished project. There are lots of wood movement calculators. Find one you like and do the calculation to see if the movement is outside your comfort zone.
None of the above is especially helpful with your current problem. Which is that your wood is cracking. go back to it's origins. Was the tree diseased? Did the sawyer know what he was doing? Was the wood properly stickered? Is it just end cracks? Etc.
Sorry, not really much help.
It's not too dry. It likely cracked while it was drying. Once it's cracked, there's really nothing you can do. You can't unring a bell.
I am not sure that is fully true, the cracks that are showing up are where pocket hole screws are. I have used pocket hole screws and red oak many times before with no noticeable issues. It is from a different supplier, so the quality could be very different.
This is your first mention of pocket holes & screws. You might want to re-state the question to get useful replies. If I asked about trouble with cracking without mentioning that I drove a truck over it every day I might not get the help I sought. It does not sound like a moisture issue anymore.
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