I've had this wooden yard/metre stick for years....
Before we met for the Second Tuesday to make the vignette settings, I was measuring off the pieces of foamcore to get people started on making the vignette settings.
I measured in the 10 inches from the edge: then, because my aluminum carpenter's square was only 24" long, thought I would use my wooden yardstick. None of my measurements matched.!
So I put my yardstick on my kitchen counter...
The kitchen counter is FLAT!
The yardstick is SO out of level!!!
I wish I could show you but my camera won't show it properly!
It's weird! If I put the yardstick one way it curves SO much that there is a 1/8" gap in the middle. If I put it on the other side, it's level for about 24" then it curves up about 1/16".