One of the applications of the oxalic acid is to remove rust from metal parts. It is especially suitable for steel parts that have been chrome-plated, such as bicycle parts. The reason for using it on chromed parts is because the oxalic acid will not eat the chromium as it does with other metal cleaners, which contain stronger acids such as hydrochloric acid.
What is a chrome plated part?
Let's see how to remove rust with oxalic acid. As we have already mentioned, this method is very good for all metal parts, and especially useful in the case of chromed parts, as oxalic acid will respect the chromium layer, without eating it.
A chrome-plated metal part is a piece of steel that has been given a chrome treatment to give it a shinier appearance. It has an aesthetic effect on parts. You can see it on cutlery and hardware. In this image you can see examples of chrome plated parts.
How to remove rust with oxalic acid
- Clean the parts to be rusted with soap and water to remove dust and other particles.
- Take oxalic acid (it comes in powder form) and dilute it for a few minutes. 100 grams per litre of water in a basin or bucket
- Introduce the oxidised parts. Depending on the degree of oxidation, you will have to leave them more or less time. On average 2-3 hours should be sufficient.
- Remove the parts and rinse them thoroughly with water to remove the rust.
- Dry the parts thoroughly. This drying is important to prevent them from rusting again.
- To make them last longer, you can apply a layer of grease or grease lubricant. This will keep the parts in good condition for a longer period of time.
This product is especially widely used in bicycle parts. Let's take a look at this particular case for bicycle parts.
How to remove Bicycle Rust
Materials: You will need 200 to 300 grams of oxalic acid400 fine-grit sandpaper, steel wool 00, tools for dismantling the bike, degreasing cleaner, brush, etc.
- Dismantle the bicycle : It is possible to do the work without disassembling but you will not get a good result, so it is better to disassemble the whole bike. Once the bike is completely disassembled, separate the rusted parts. The rusted parts will be steel or iron, as aluminium parts do not rust. It is important not to put the aluminium parts in contact with acid because of the reaction they could cause. Then remove all the grease and oil from the rusted iron or steel parts that you have separated.
- Preparation of the oxalic acid solution: Wear gloves and goggles to avoid direct contact with the acid.. In a cube prepare two tablespoons (about 100 grams) of oxalic acid per litre of water.
- Introduce the rusted parts into the solution: Put the rusted and cleaned parts of the bicycle into the solution. The parts should be placed in such a way that they are completely submerged. Let them stand in the bucket for 24 to 48 hours. The oxalic acid acts by dissolving the layer of dirt on contact, it is not necessary to rub the parts.
- After soaking for 24 to 48 hours, remove the pieces. The pieces will be covered with a white layer that should be removed directly with soap and water.
Review: Check each piece and try to correct any small defects such as scratches. Remove them with fine-grit sandpaper.
Riding the bicycle: Once all the parts are clean and dry, it is time to reassemble it with the utmost care. The bike will be as good as new.