I have a tung oil finish on claro walnut that is around 6 months old and is showing some white flecks in the pores that do not go away with reapplication of the tung oil. What is this and how can I get it to go away?
From contributor J:
I often fill the pores on walnut to keep this from happening. Dust gets in the pores, which results in light pores on dark wood. In that case, you can use a tinted wax to fill the pores.
If it isn't dust, maybe it's poorly dried (too thick) tung oil. I would still try the tinted wax, since more oil doesn't fix the issue. I use Liberon Black Bison, though there are other brands.
I like to fill the pores with Rockler's Wunderfil. Louis and Co has a great waterbased filler too, but it smells like an electrical fire (though it's supposed to be non-toxic). Many of the oil based ones have resin in them, which may not work so well under an oil finish.
If this was a tabletop, it could be that oil built up in the pores and couldn't leak out. You may consider blowing compressed air into the pores and wiping off the excess to keep the oil from drying too thick.