Those Black Stains On Your Stripped Stock

[painter777]

Oxalic Acid

Hi Ten,
Drying up down there or still raining?
My brother has a outside stairway down to his basement that had a running waterfall on it. About 3' of water down there at the worst of it. He's needing my help but I need to stay near home, having some issues with my Mother.

Your RMC Stock,
Good that you were careful. Oxalic Acid can come in many different .... I'll call strengths. I have a 2 part mix we used at work for bleaching out stains on new unfinished wood.
Like those raw stair treads covered in muddy boot prints or single tread that is naturally 3 times darker than the others and about to be finished Natural. Fireplace Mantel tops with coffee rings... etc. This stuff will eat the flesh to the bone...... like Hydrogen Peroxide on steroids.
Usually treat the stain, once gone a quick light wash with it over the entire piece of wood, sometimes having to neutralize it. Best for full strip and refinish jobs.

When possible light precise dobbing and brushing of the Bar Keepers can give great results.
But it can take 6 or more applications on bad blackened spots. Then finish up by quickly wiping the entire surface with it and damp rag it off so it blends. This way the treated area won't stand out.

If I got it on the unstained wood next to the stain it was lightening that area. Maybe it wasn't bleaching the wood as I assumed and was changing the oil color instead

It was bleaching both the wood and the oil. We'd mask off any area we didn't want it to 'Bleach'.
I've seen others instead of masking off, they'd use water and soak the area they didn't want the 'Bleach' to contact. I prefer masking and being neat, unless doing the complete piece.

I'd buy the 2 gallon kit. But advise only using when all others failed. Here's a pic of the kit and a link to some before and after pics. Used 1 part to 1 part it will strip all the old finish to include any rack paint. A last resort thing.



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