Alltrade makes their jam nut valve-adjusting tool to deal with engine valve jam nuts, but you can also put it to work on jam nuts in non-automotive applications such as X-Y tables. Their jam nut tool solves the common problem of how to tighten a jam nut on a slotted stud without turning the stud.
Some other jam nut tightening solutions use multiple tools, but Alltrade wraps a nut driver with a 7-1/2″ pivoting handle around a slotted screwdriver to create an all-in-one tool. They also thoughtfully cut a window into the nut driver so you can see if the screwdriver blade engages the slotted stud.
Alltrade manufactures two version of the jam nut tool, one for 10mm jam nuts and another for 12mm nuts. For a simple tool that lists for over $30, you’d think you were buying from Snap-on, but you can find these jam nut tools for about $13 if you look around.