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I am refinishing an antique interior door for our bedroom.

I scraped off the old varnish type finish, maybe shellac, and sanded to bare wood (220 grit).

I applied oil based "Old Masters" semi-transparent stain, wiped off the excess and let dry for 3 days.

Then when I applied the first coat of "Formby's" Tung Oil Finish the stain seemed to liquify and wipe off onto the rag I was using to wipe off excess tung oil.

Can anyone tell me why the dry stain lifted?

  • Hi and welcome. The Formby's finish I think you'll find is called "Tung Oil Finish" not tung oil. If that is what you're using it's rather infamous for not being being tung oil and in fact for not having any tung oil in it. It's merely a marketing name. What it is instead is something very similar to other company's "Danish oil" products, which are simple blends of varnish and oil, with added solvent. It's the solvent base that is dissolving the dry stain, which presumably is an oil-based stain (clean up with mineral spirits yes?) – Graphus Nov 15 '20 at 8:06
  • Sorry ran out of room. Also, maple is a dense, close-grained wood that doesn't absorb stains well, so it contributes to the problem — so a lot of the stain is simply sitting on the surface of the wood and is readily wiped off. – Graphus Nov 15 '20 at 8:08
  • Graphus-Thank you for the insight. – user9409 Nov 16 '20 at 21:24
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Formby's were1 rather infamous for their "Tung Oil Finish" because it isn't tung oil and actually never contained any. It's a cornerstone example of how product names in the wood-finish market are unregulated and can be very misleading!

"Tung Oil Finish" is instead a product very similar to (or identical to) what other manufacturers sell as "Danish oil" — a simple blend of oil and varnish, with added solvent to make it thinner.

And it's the solvent component that is likely the main culprit here as any product with some solvent in it2 can redissolve partly dried oil-based products that were applied previously. While you let the stain dry for 3 days even in warm and dry conditions this might not be long enough for complete 'drying' (i.e. curing). Curing takes considerably longer than the touch-dry time.

Also, if the door is indeed maple this is a dense, close-grained wood that doesn't absorb stains well. So it's likely to be contributing to the problem as some or a lot of the Old Masters stain may simply be sitting on the surface of the wood, readily wiped off. If you didn't thoroughly remove the excess as per the applications guidelines3 you could find that even wiping with a dry cloth could noticeably colour the rag or paper towel.


1 Now Minwax.

2 And there's more than 50% in "Tung Oil Finish"!

3 E.g. "Before the stain dries, wipe off excess stain with a soft cloth, first across the grain, then with the grain."

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