Cherry Warping

[Scott Sonnenberg]

Hi Guys,

I'm dimensioning cherry by hand. I started with 4/4 rough sawn and now am around 3/4" thick.
Every time I flatten my reference face, I'll come back in a day or so and it'll be warped.
The stock has been in the shop for a few months, and I've thicknessed very gradually, so I am confused as to the cause of the warping. The weather has been erratic these past few weeks, and I'm not sure if that would be the cause.

I'm coating the end grain in paste wax. Is there any other way to prevent warping?

Best,
Scott

[Bill McDermott]

Scott,

Some things that help me with this issue are:

1) Remove about the same amount from both faces. Since you talk exclusively of your reference face, I think approaching from both sides will help. This is an issue of moisture content...
2) Do not set the board down on a flat surface after planning. Rather, prop it up on stickers if it's going to sit there overnight(s).
3) Make a spare of important pieces, or keep some extra material just in case. Sometimes the fix is to replace the board. This is an issue of releasing tension, not moisture. This movement happens very quickly, but you might not notice it for a while.

I've seen others who sticker and then clamp or weight their prepared boards so that they cannot warp before assembly.

I hope you still have all the wood you need for the project. Good luck.

[Mike Cherry]

Weather can have an effect as well. It's just one of those things you deal with as a woodworker. Doesn't matter if you are a Neanderthal or power tool guy. You got some good advice already. I would just add that when I resaw drawer sides and such, I leave them a little thicker than needed so that if the warp, I'll have a little wiggle room. The upside to a lot of this, is that normally I don't work from a cut sheet so I have freedom to make changes on the fly. I think what I am referring to is called relative dimensioning. It's my favorite part of hand tool woodworking.

[Jerry Thompson]

I have to take all of my almost dimensioned lumber in the house from my garage shop. I put it in a spare room and let is sit for about a week. This has worked for me. I also do not take off a lot to start off with. I still place it in the house and proceed to take a little off until have about an 1/8 inch is left.
I spent too much time on one project with warping to let it happen again.

[Joel Thomas Runyan]

Big component is how it was sawn. A bit of run-out on a flat sawn piece means the board is never really going to *want* to be flat in the first place. Weather will just make this tendency worse. Even in perfectly controlled environments, some boards just want to be bananas.

[Brian Holcombe]

Don't know which part of the country you are from but in the northeast this time of year is the transitional weather and weird movements happen.

[Ryan Baker]

I have a lot of cherry that has the same issue. It isn't about moisture in this case, it has been inside and dried for a long time and is very dry. There is a lot of stored stresses in the boards that release when material is removed. Cherry can be particularly bad for this. Best thing to do is to remove just a little material at a time (keeping it even on both sides, as suggested, is a good idea). It will move -- expect it. Then go back and remove a little more, releasing a little more stress. In some cases the board will relax and you will be able to get it to dimension and be stable. Some boards just aren't ever going to get there. Sometimes you can work with it anyway, depending on how it is being used.