I recently used tap water mixed with Timbermate grain filler on some red oak. The iron in the tap water reacted with the tannins in the wood and caused dark spots to appear all over the wood (doh!)
I’ve tried oxalic acid to remove the stains, which worked beautifully. However, when I went to neutralize the acid (with a mixture of borax and distilled water), the mixture began turning dark and caused a lot of the stains to re-emerge.
Have any of you experienced this? Is there a solution to keeping the dark spots at bay? I feel like I’m going in circles.
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Replies
This just happened to me and I am trying to find out what to do. What happened of this?
I didn't use distilled water and I thought that maybe the iron in the water reacted and stained, but if you used distilled and it still happened then that can't be it.
Any help would be appreciated!
Oxalic acid is mostly neutralized by the use of lots of rinse water. For further assurance, you can use a weak solution of water and baking soda or household ammonia. I've never had any problems with using plain tap water. So, I can't address that. I would assume that the distilled water with the baking soda would be OK.
If it was due to iron content of your water then the iron is there forever. Unfortunately there is nothing that will get rid of the issue. Them little molecules tuck in there and stay forever.
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