You might want to edit the post and change that to "hardening," since the tung oil and other hardening oils harden, rather than dry ("[T]ung oil is a drying oil. . . ."
This might be a regional thing. Nearly all the references I see to Tung, Linseed or Walnut oils use the term "
drying oils " as opposed to a search for "
hardening oils" returns mainly references to oils used in hardening metals during the quench.
...keep in mind, some tung oil is pre-polymerized, so you do not have to wait any longer than you would if you were applying polyurethane, before you add the next coat.
I am only talking about pure Tung oil here. not Tung oil finishes or other modified variants.