Natural Pore Filler for a Tung Oil Finish

A finisher gets suggestions for filling pores on Walnut stool tops before applying Tung oil. July 3, 2008

Is there an ideal pore filler for a tung oil finish? Is there a green pore filler? I'm doing tests for some walnut stools for a restaurant and I want an easy to repair and dark finish for it. I've had luck with pigmented wax, but will that migrate onto clients clothing?

Forum Responses
(Finishing Forum)
From contributor D:
How much experience do you have with water or chemical dyes? If you feel comfortable with them then I suggest you use potassium permanganate to dye your pieces with, then apply a thin coat of tung, let it dry, then apply a linseed oil base grain filler - the old kind not the new fast dry type. After that has thoroughly dried apply as many coats of the poly tung as you desire for build - usually three is sufficient. This way no color is on the surface of the wood. The pores will be filled well and the finish will still be quite repairable with the PP and tung as you go

From the original questioner:
I've used a variety of chemical and water dyes, but not that one. Do you have a good source for it? Same with the grain filler: what brand is the type you suggest and where should I buy it? Can I make my own?

From contributor C:
If you have a fairly local Culligan water softener dealer you can get it there for about $25.00 in a container. I know someone still makes the LO filler but I donít know it off-hand. Donít exceed 4 oz. per gallon of the PP. Start with 1 oz. per gallon. Make up just what you think you'll need. It loses its potency after a short while.

From contributor R:
Jasco makes what they call a natural wood filler but itís kind of a yellowish/tan color. From my experience you can add oil colors to it as well as dry powders.

Wood-Kote out of Oregon makes a paste wood filler thatís as white as typing paper and you can add colors to it as well. UTC or artist oils or the powdered dye colors work pretty well, just stay away from the water soluble ones because you can mix it up until the stars fall from the sky and they still wonít dissolve.

From contributor C:
Contributor R - is Jasco the old type linseed oil base filler? This is what will be needed - and for his use oil colors would be best.

From contributor R:
Yes the Jasco formula is of a linseed oil base as is the paste wood filler from Wood-Kote. The only difference between the two is the color. As far as the color itís up to the user. If you went with the powders you might want to mix them up first in some Naptha and then add the mixture into the filler. The oils seem to mix up rather easy into either of the two fillers.

From the original questioner:
Just an update: after trying out Wood-Kote, the fact that it left the surface looking glossy made me a little nervous about the compatibility with the Tung finish. It seems that the test I liked the best was with Rockler's Wonderfil, which sort of surprised me. It filled well enough for my purposes in one coat, smells like nothing, sanded and cleaned up easily, and looked great with an oil finish! One application before sealing the wood was enough for the job. Unless someone can come up with a reason why this is unwise, I think I have a winner.