Dark water stains on solid wood.

[Michael Lloyd]

Hello, can someone help me please? This oak, I think, skirting board has been water damaged due to a leaking cistern years ago. I'd rather keep the natural wood, rather than paint over it, but I'd like to make the dark staining less obvious if I can. I've sanded with 60, 80, 120 and 150 and the photos show the current state. I intend to cover with Fiddes hard wax oil, which has a slight tint to it, so it might mask it a bit, but if there's anything I can do beforehand then I'd like to try. I've searched the net and suggestions include: bleach, toothpaste and vinegar, but I don't feel confident without the advice of an experienced woodworker.......

 

[Bingy man]

I don’t have a real answer for you but I’ve never had any real success with water stains as mineral within the wAter can react with the wood . If it was a long term leak it’s even harder . There are few previous posts on similar issues that could help you untill a member with more specific help can help you . Use the search function.

 

[Cabinetman]

It should come off with a plane, couple of strokes should do it, there is a bit more at the bottom further along as well. But this will lighten the wood a little as the rest will have darkened a bit from exposure to light.
If a plane isn’t an option for you, you might find a scraper easier.
Ian

 

[mrpercysnodgrass]

Hi Michael, This is the stuff that will do the job.
https://www.agwoodcare.co.uk/products/liberonwoodbleacher/
Just be aware, oxalic acid is very poisonous so take care if you have young children or pets. Rinse off with plenty of water once the stains are gone, you will probably have to sand again with 150g before applying the hard wax oil.

 

[XTiffy]

I agree with the above use of oxalic acid. Any chemical should be handled with care I have used oxalic for more than 45 years without any problem. Oxalic acid is found in rhubarb (maybe explains why I can't stand the stuff!).

 

[mrpercysnodgrass]

It is only in the leaves of rhubarb which you definitely cannot eat, also in spinach leaves but not so concentrated.

 

[Michael Lloyd]

Thank you all so much for your advice. I've got the Liberon on order as there are also other harder to reach parts of the house that would benefit (beams on ceiling of room beneath the bathroom) but I gave it a go with the only plane I have, but I struggled with that.... I need to learn how to sharpen it, but I also tried a scraper... AMAZING! Took less time than I thought and a decent result.... see pics, before and after. Thanks all, again, for helping someone who knows little, but is keen to learn.