Black Rust Stains in Wood

[Guest]

Any old salts out there got a cure for reducing black rust stains in mahogany prior to varnishing, I tried bleach with little effect.

 

[Guest]

Try oxalic acid. I think you can still get this from a chemist. It's in fine crystal form, soluble in water. I don't remember the ratio but 3 to 1 by volume should work. Paint solution over bare affected surface, leave for a minute or so and then rinse with water. You may have to repeat. Go easy and try on a test patch first.

 

[Guest]

Many thanks Syd for the info.

 

[Guest]

Oxalic acid isn't very effective on mahogany. Try 'Rustins Two Part Wood Bleach' from any good (trade) paint supplier. Did the job for me.

Ian.