9 Out Of 10 Panels Stay Flat

After planing the panels to thickness I cut them all to their finished size. I stickered them and set them aside for a few days to do some other work. Well, in the interim, one of the panels developed a cup, worse at one end.

The worst end. Cupped by almost 1/8".

The other end is cupped less than a sixteenth of an inch. There also is some wind.

Dang! I hate when that happens. The reason wood cups is because the cupped (concave) side has dried quicker or more than the convex side. When resawing lumber one hopes that the wood will behave but sometimes this is not the case. You are always taking a chance.

The "good" end I could deal with but the "bad" end is a problem. If it doesn't come back on it's own I'll have to do something. My choices are:

1)Flatten and thickness plane again, resulting in an under thickness piece.

2) Clamp it flat while cutting the tongue and hope the cupping doesn't cause a problem when installed.

3) Flatten it by dampening the concave side making the fibers on that side swell, then quickly cut the tongues and hope the cupping doesn't cause a problem when installed.

4) make a new panel.

Having one undersize panel is not a workable option and I would not want to thickness plane all the panels since this would either have to be done all on one side, allowing for more possible winding and cupping, or, if planed from both sides it would seriously affect my bookmatches. The two choices that involve hope, while tempting, are not attractive to me, although with a beefier frame? well, I think not. If necessary therefore, I will make a new panel.

I have set the panels aside for a while longer to see if anything changes, then I will have to deal with that cupping. I have decided to wait a bit to cut the tongues on the panels. I'll start milling the walnut to final dimensions while I see how that panel does.