I have some dark water stains on my hardwood oak flooring that I would want to remove. I read here that oxalic acid is a good way to approach this.
The problem is I cannot find any. At Home Depot they looked at me like I awas from another planet and had never heard of it.
Does it perhaps have another name so I can find some?
TIA
Ingredient in some rust removers.
Sherwin williams has it, but I dont think it will work.
Some deck cleaners are oxalic acid. There's usually the bleach based cleaners and then the oxalic acid based cleaners and then the lye based cleaners. Read the labels to get the right one.
If the floor has any kind of finish on it, all bets are off as to what will happen.
-dickm
On Wed 10 Sep 2008 05:07:47a, Norminn told us...
Barkeeper's Friend contains oxalic acid. You could make a slurry of it with water. It is also slightly abrasive. It will take dark stains out of wooden countertops. Of course, whatever course you try, you will most likely have to refinish those areas. Most any product will damage the top finish to get at the stain.
You can get it at Ace Hardware.
If you want almost pure oxalic acid, get Savogran Wood Bleach. Here is a link to the MSDS:
As others have noted, this might not work for what you are trying to do.
But it's probably worth a try.
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I suspect they do have it; just the flunky you ran into didn't know what it was. It'll be in the paint department w/ the strippers, etc.
Look for "wood renewers" or similar type of words.
As someone else said, many of the deck cleaners HD sells are o-acid based--we used one from there by the 5-gal bucket-load on the old barn altho I don't recall the particular brand.
Ace or any paint store or decent hardware store will have the crystals as well which normally is more cost-effective altho for small amounts you're not going to care too much.
As for the application, be very careful--it's a very strong bleaching agent and while it'll help on the water stains, it'll bleach the wood, too. I would _strongly_ suggest finding a closet or other inconspicuous area of the same flooring and making a practice run there before attacking the main floor or you may discover you have a worse-looking white spot to try to match than the existing stain leading to a full floor resanding... :)
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I don't think this is a good idea for wood. If it does remove the water stain, it will leave unsightly marks. Have you tried mayonnaise? If that doesn't work, a refinishing floor job is in your future.
Look for "wood bleach" but be sure to read the ingredients before you buy to make sure it's based on oxalic acid and not something else.
If you can't find it in a hardware store or big box, try a paint store (i.e. one that sells only paint and painting supplies, not a hardware store that also incidentally sells paint).
Common ingredient in automotive radiator flush. HTH
Joe
Hello,
Oxalic Acid can be found as the active ingredient in many deck cleaners. Just read the label. You might also be able to find Oxalic Acid crystals in a good paint or hardware store. It is also found in single component "Wood Bleach". Again, read the label.
You will have to strip off the remaining finish above the water stains so you can apply the acid, as a concentrated Water solution. The problem you are going to have is that in addition to removing the black stains, it will lighten the wood just enough to make it obviously different. That means stripping off enough of the finish and treating a large enough area such that you can make the change in color occur at a visually natural place on the floor.
If you use Oxalic Acid, let it dry over night and don't let any people or pets touch it or eat it. It's fairly toxic. After it has dried and assuming the floor doesn't need a second treatment, wipe it up with a damp rag. The solid will make you sneeze big time so don't dry brush it off the floor. Dry brushing will just sweep the smallest particles into the air. Go over the floor with a Water solution of Borax to neutralize any residual acid. Wipe down the Borax dampened floor with some fresh rags, let the floor dry, and you are good to go.
Good Luck.
Why would you caution against using it on wood? Oxalic acid is the "original" wood bleach. In good paint stores it is sold as wood bleach. It is the best way that I have found to remove iron based stains. Works well on stainless steel kitchen surfaces too.
Oxalic acid is somewhat toxic. However, that is a matter of how much you ingest. Oxalic acid is found in small quantities in green, leafy vegetables like spinach. It's also the precursor of the most common kidney stones (calcium oxalate.)
You are correct sir! The amount you could ingest by touching it and then accidentally putting your fingers to your mouth is significantly greater than what you would ingest from green, leafy vegetables. The bigger issue is actually sneezing. You haven't really sneezed until you've gotten even a little of the dust in your nose.
Good Luck.
Well - just an update to close the loop. I tried some regular bleach on it and now it really looks like hell. The wood was not originally stained, just the verothane or whatever giving it a slightly yellowish oak look with a sheen on it. Now it is white with really dark blotches. lol
I think I will take the tried and true route and pick up a few squares of the hardwood - I'll have to trim a bit since the new stuff is metric and mine is old enuf to be all imperial measurements. I'll just knock them out and replace and then spot sand to the same level and touch it up. Has tro look better than it was and is now.....
thanks for the information anyways!
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