Follow these steps to remove ink stains from wood:
- Dilute oxalic acid in warm water and apply with an artist's brush to the stained area. Caution: Oxalic acid is poisonous, so wear rubber gloves when applying it.
- On painted surfaces, wipe with a cloth moistened with detergent suds.
- For unpainted or stripped surfaces, after applying the oxalic acid, neutralize the area with white vinegar and rinse with rubbing alcohol. Allow to dry. Note: Permanent inks are almost impossible to remove.