Oxalic Acid ~ Has Anyone Used It?
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Posted by K.Duffy (+1807) 9 years ago
I'm trying to save my Drexel Declaration dining table. I was using it for a plant stand and there's a huge black ring in the middle. I've sanded the finish off, but no change for the black ring.

"On the Internet" I've found recommendations to use oxalic acid to bleach it out. Sounds easy enough, must be true *Internet* but I'm hoping someone like Amorette has tried it before?

P.S. Thanks Amorette for the tip on boiled linseed oil several years ago! I use it a lot (even tried it on this table...)
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Posted by Amorette Allison (+11902) 9 years ago
Sorry. I don't even know what oxalic acid is.
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Posted by Mrs. M (+716) 9 years ago
The problem with it or with any bleach is it leaves the wood whiter than the rest or in my experience a weird yellowish color. Would you want to put a high sheen black painted top on it and seal it? If you decide to do that, I would put a varnish surface down first to protect the wood grain from paint particles. Then scuff it up and paint. That way if you ever what to go back and try to get water mark out there will not be pigment in your wood.

[This message has been edited by Mrs. M (1/3/2013)]
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Posted by Cindy Stalcup (+591) 9 years ago
You could try lemon juice, hydrogen peroxide, or even CocaCola. They each will mildly bleach the black tannin stain on the wood. I would use a Q-tip & just put it on the black part. Place it in sunny window to heighten effect or try a hair dryer.

If it is a mild mark, run a hot iron over a white tshirt on the spot. That will always take off a white watermark from a table.

The Oxalic acid is the chemical in deck restorer. It is quite strong and seems to take a bit of the wood off when you use it. Use a mask. It will take the black mark off though. You will have to lightly bleach the entire top to make your new stain finish come out even.
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Posted by K.Duffy (+1807) 9 years ago
Thanks all! I really like the walnut finish ~ so I think I'll try some of the less invasive suggestions.
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Posted by Richard Bonine, Jr. (+15076) 9 years ago
I have heard that if you repeatedly drop a bowling ball on the table you can give it a "textured" look.
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Posted by worldmom (+416) 9 years ago
I used oxalic acid to get rust stains (from our well water) off our fence, but I don't know what it would do to wood. Can you try it on the underside of the table and see if it bleaches the wood?
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Posted by chizzer yuprod (+20) 9 years ago
If you use the bowling ball, do put that much of hook on it it might "split".
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Posted by K.Duffy (+1807) 9 years ago
See what you started, Richard? Good ones though..
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Posted by Gunnar Emilsson (+17667) 9 years ago
Oxalic Acid is the main active ingredient of OxyClean(tm). Think Billy Mays.

I use Oxyclean all the time. Can't say I have ever used it on wood, though...stainless steel, plastic, it works great.
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Posted by K.Duffy (+1807) 9 years ago
Cindy: I tried every tip, except cola, on sections. The lemon juice was the most noticeable ~ thanks!

Gunnar: I had "assumed" the Oxy was for Oxygen..of course my bottle of it is empty, as I also use it on everything..
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Posted by Jeff Denton (+757) 9 years ago
I bet if you dropped acid and then went bowling you'd get a textured look, too. Ha.
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Posted by Richard Bonine, Jr. (+15076) 9 years ago
Jeff... spare us.
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Posted by Bonnie Boggs (+50) 9 years ago
I was just recently talking to a geologist about cleaning crystals and he suggested Oxalic Acid. I checked with several stores who then suggested a pharmacy. I talked to two pharmacies and they were unsure of where to find it and thought possibly a chemical company. It seems to be a very difficult item to find. I then talked to the original individual and told him of my problem finding it and he suggested a rock shop or catalog selling rock supplies. In the mean time he suggested using white vinegar or diluted clorox. I sort of worry about both as they are pretty strong. Good luck.
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Posted by David Schott (+17439) 9 years ago
Sears has this:

Savogran Wood Bleach

"Contains Oxalic Acid Which When Mixed With Hot Water Effectively Bleaches Unfinished Or Stripped Wood Quickly & Easily Concentrate Mixes With Water. Used for removing black water spots and tannin stains in woodUse on all unfinished woodwork, floors, doors ect. to lighten wood or match different wood color."

http://www.sears.com/savo...ockType=G5

You might want to try Steadman's Ace Hardware, Sherwin Williams, or one of the other hardware stores.
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Posted by cj sampsel (+485) 9 years ago
The only thing I know about oxalate is that is one of the main components of kidney stones.
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Posted by Cindy Stalcup (+591) 9 years ago
You might as well give CocaCola a try. It definitely takes dark black stains from old hardwood floors.
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Posted by Gunnar Emilsson (+17667) 9 years ago
If any of your crystals are calcite, you sure don't want to be cleaning them with vinegar.
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