"vinegar and CLR" 0
Made me think of my very old can of liquid wrench.
Very similar problem indeed...cleaned the areas that got wetted very
nicely but the fit around the ball stem in the handle was too tight and
no way to get the solvent to the area needing it.
Although in this case w/ both being actual reactants rather than simply
a wetting agent, I suspect w/ sufficient time they would have
_eventually_ dissolved enough to make the handle "let go", but I was
tired of waiting...
Similar problem w/ most of the wetting agents for rusty fasteners --
they're not able to actually get into the area that really needs it as
the corrosion products effectively fill the space. They certainly help
if ever get it broken loose have some aid in many cases, but just don't
solve the problem in many instances...