I’ve started turning a piece of walnut stock I had on hand into a pair of winding sticks.
I’ll inlay the sticks, a bit like http://www.walkemooretools.com/winding-sticks/, for better visibility.
The first step is simply to plane the stock square, rip it in two, and then re-true it.
This 2nd image is of one end, with about 80% of the rip cut made. The other end is still joined, and you can see that the two pieces have twisted a bit as I rip them. The half further from the camera has lifted up, by perhaps 1/32nd or so.
Fortunately the two pieces are still reasonably flat after ripping – they didn’t twist too badly. Not as flat as they were, but not bad. I’ll let them sit a while, then take the plane to them again.