I prototyped this attractive wooden sit/stand laptop stand
but ran into a problem keeping the legs tight enough to hold their position. There are 1/16" thick EPDM washers between the oak legs - the washers are almost 1.25" in diameter with a .25" hole for a threaded tension rod. If I want to resist about 15 lbs of force on a 8" lever arm, that's only about 10 ft-lb of torque that I need to resist. What the hell, let's say 20 ft-lb.
I tried to find a toothed washer that I could use in pairs, each one epoxied to one of the oak legs, but couldn't find a suitable design. (For example the Nord Lock wedge locking washers won't work because they are directional. They will work on one side, but on the other the rotation will be in the wrong direction.)
What alternative material(s) should I use which might resist that rotation?