I purchased some white oak from a local mill about 2-3 months ago. The wood had been stickered and covered outdoors. The guy I bought the wood from claimed that it was aged just about the minimum necessary for use. I stored the wood in my garage (a very stable environmet)for 2-3 months before use.
The other day, I jointed then planed the wood from about 1" down to
1/2". The boards were perfectly flat. Within 24 hours almost all the boards had warped --not drastically, but certainly noticeably to the eye. I was surprised at the amount of movement in just 24 hours. Is it a simple conclusion that this wood is not dried enough? Could I have released tension in the wood by planing it so much so quickly?
Are moisture meters an essential tool when most of one's supply comes from a local rough cut mill?
You really need to plane both sides equally. The center of the board has more moisture than the outside surfaces. You can try another board, or you can paint the ends of the boards with white glue or wax and let them dry for another year. They really need to be under 10% moisture (6 is better) to have stable wood. max
What's the air humidity in your garage, and did you sticker them ?
Pretzel city. If they were quarter sawn then you'd barely notice it, but if these were the usual flatsawn stock, then taking half the thickness away is going to cup them like crazy. Do you have much twist in there ? Just how bad is this movement ?
There's a difference between "dry" and "dried enough". You can kiln it and get it down to a low MC in no time at all. But this doesn't make the wood stable - if you expose it to some more moisture then it will absorb it and the MC shoots up again. It can easily show "reverse case hardening" behaviour in this state. If it was originally air-dried, then it's unlikely to show case hardening though.
If you want stable timber, then you have to wait a few years. Let the timber go through a few seasonal cycles - each one will become slower and less severe for movement, even though the MC still varies. I wouldn't use air-dried oak after only one season, even if the MC was low on that day.
If you have some full-thickness ends to play with, do a tuning fork test. Take a long narow slice, saw a groove down the inside to leave two long legs. See which way they move.
I don't have much use for a moisture meter - I prefer an air hygrometer and waiting for equilibrium. Unless you spend a lot on a meter, they're just not that accurate. Buying timber of unknown MC though, that's a good time to have one.
I'd still rather know what the drying history has been so far. I'm rarely buying timber to use immediately, so a summer in my own racks will get the MC down pretty well anyway.
What is "warp" to you? Wood behaves predictably when drying, it bends toward the formerly wet, so you should be able to pinpoint your problem quickly, rather than sift through speculation.
formatting link
for air drying.
formatting link
for storing, admittedly on industrial scale, but informative.
24 hours? Ha, try minutes..This is the nature of woodworking. Even the best of air dried, kiln dried woods have a mind of their own. As suggested, planing down equally from both sides helps. You might also consider roughing out your stock, let sit several days and then machine to final size. Moisture meters are cheap, pick one up.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.