I used pure tung oil on the doors and a lot of trim in my house remodel recently - all of it VG fir. For the trim, I oiled them in place, since I wanted to patch the holes. For the doors, I oiled most of them in the garage. It certainly worked better in the garage, since I could position them flat and flood the surfaces to let the oil soak in really well before wiping the excess.
In the end, I don't know if it mattered - some of the doors came out better than the trim, some sections of trim came out better than the doors (fir is funny). One nice thing about it was going over places that I missed - it blends in really well. Also, since it soaks in so much, if it gets scuffed, its not as noticeable as surface finishes. Maybe prefinish it, and touch up any spots where you have to cut or expose raw wood during the install. Maybe polymerized or modified tung oil would act differently. I don't know. This is just my first (but extensive) use of tung oil.
Pure tung oil is slow to dry. Months after finishing, there are still areas that feel oily, but I got tired of rubbing. I had a section of ceiling that I wanted to oil, and rather than use tung oil, with the multiple coats and slow drying, I used Rubio Monocoat with an accelerant (it's what I used on the floors). Looks very similar and was much easier to apply. But if the client wants tung oil, who are we to argue...
Scott
I usually keep a bunch in my car but I had to rent a uhaul to deliver the cases yesterday and forgot to take some cards with me.
