Oxalic Acid Crystals
Overview
Oxalic acid is a premium solution for restoring and maintaining wood’s natural beauty. As an oxalic acid wood bleach solution, it lifts watermarks, rust stains, and discolouration without damaging the wood grain. Often chosen over other bleaching methods, this oxalic acid cleaner can freshen wood surfaces, making it a staple for professional wood restoration projects. If you’ve wondered how to use oxalic acid effectively, read on for guidance on mixing, application, and neutralisation steps.
Preparation
- Mixing ratios: Dissolve about 60 grams of oxalic acid crystals per litre of warm water for a saturated solution. Some undissolved crystals at the bottom indicate maximum strength.
- Alternative solvent: Substitute water with methylated spirits for quicker drying and recoating.
- Safety measures: Wear gloves and eye protection, and ensure proper ventilation when preparing your oxalic acid for wood solution.
Application
- Initial application: Evenly apply the prepared oxalic acid mixture with a brush, cloth, or sponge across the entire surface to avoid uneven bleaching.
- Processing time: Visible results often appear within 20-30 minutes, and the bleaching action continues for 1-2 hours.
- Multiple treatments: Reapply as needed until the desired level of bleaching is achieved.
- Neutralisation: Stop bleaching by rinsing the wood with water or methylated spirits. Rinse thoroughly after using spirits.
- Final steps: Let the wood dry before sanding the raised grain. Proper sanding ensures even staining or finishing after using this oxalic acid wood bleach solution.
After Care
Keep the wood dry, periodically clean it with a mild, pH-neutral cleaner, and reapply finishes as necessary to preserve the wood’s natural beauty over time. Using oxalic acid for wood periodically can help maintain consistent colouration and prevent future stains.
Frequently Asked Questions
Who can buy Oxalic Acid?
Oxalic Acid crystals are now classified as a regulated poison, therefore, oxalic crystals are no longer available for sale to the general public.
If you are a business or a professional user, you can still purchase Oxalic Acid crystals providing that you confirm you are a business or professional user.
What types of stains can Oxalic Acid remove?
Oxalic Acid is highly effective at removing iron and rust stains, tannin stains, and watermarks from wood surfaces. It can also be used to clean and restore stone, concrete, and metal surfaces.
Is Oxalic Acid safe to use on all types of wood?
Oxalic Acid is generally safe for use on most hardwoods, including oak, mahogany, and teak. However, it is always recommended to test the solution on a small, inconspicuous area first to ensure it doesn’t affect the wood’s colour or texture.
Can Oxalic Acid be used on exterior wood?
Yes, Oxalic Acid is effective on both interior and exterior wood surfaces. It’s commonly used for restoring outdoor furniture, decks, and other wood exposed to the elements.
How should I store Oxalic Acid crystals?
Store Oxalic Acid crystals in cool, dry place, away from direct sunlight and out of reach of children and pets. Make sure the container is tightly sealed to prevent moisture absorption.
What precautions should I take when using Oxalic Acid?
Always wear protective gloves, eyewear, and clothing when handling Oxalic Acid. Ensure the work area is well-ventilated. Avoid contact with skin and eyes, and do not inhale the fumes. If accidental contact occurs, rinse immediately with water and seek medical attention if necessary.
Can Oxalic Acid be used in combination with other cleaning products?
Oxalic Acid should not be mixed with other cleaning products, especially those containing bleach or ammonia, as this can produce toxic fumes. Always use Oxalic Acid on its own and rinse thoroughly before using any other cleaning agents.
Is Oxalic Acid environmentally friendly?
While Oxalic Acid is biodegradable, it is still a potent chemical and should be used with care. After use, ensure that the solution is neutralised and disposed of properly, following local regulations.
How does Oxalic Acid compare to other wood bleaches?
Oxalic Acid is often preferred over other wood bleaches like chlorine or hydrogen peroxide because it is gentler on the wood and doesn’t alter the wood grain. It specifically targets iron-based stains, making it highly effective for certain types of discolouration.
Can Oxalic Acid wood bleach remove mould or mildew from wood?
Oxalic Acid can help lighten the stains left by mould, but it is not a fungicide. For mould removal, it is recommended to use a dedicated mould remover first, then use Oxalic Acid to treat any remaining discolouration.
How long does Oxalic Acid solution last once mixed?
The oxalic acid solution is most effective when used immediately after mixing. However, it can be stored in a sealed container for a few days, but its potency may decrease over time.
How long does it take for Oxalic Acid to work on wood?
Oxalic acid typically shows noticeable changes on wood within 20-30 minutes of application. The bleaching action continues for about 1-2 hours. Depending on the severity of the stains, multiple applications may be required.
Is Oxalic Acid the same as vinegar?
No, while they are both acids, oxalic acid is much stronger than vinegar so it will be more effective at reviving and cleaning wood than at-home remedies.