Bronze candlesticks and figurines give the interior an uniqueness and a special aroma of antiquity. They can be extremely beautiful, but they have one drawback. Bronze objects under the influence of moisture and air, as well as other unfavorable factors, become covered with a blue-green coating of oxides. This is especially true of things that were stored in basements or attics. Bronze items can be brushed to give them their original appearance.
It is necessary
- -sulfuric acid;
- -potassium bichromate;
- -ammonia;
- -acetic acid;
- -water;
- -wood sawdust;
- - soda ash;
- -protective glasses;
- -glassware;
- -latex gloves;
- - woolen rag;
- - wax or paraffin.
Instructions
Step 1
If the bronze has not oxidized too much and only individual spots on the surface need to be cleaned, use the following method. Degrease the item by rinsing it in warm soda ash solution. Rinse with water.
Step 2
Make a porridge with acetic acid and sawdust. When the sawdust is swollen, use the resulting mass to wipe the bronze object with a woolen cloth. At the same time, acetic acid corrodes oxides, and sawdust polishes the product. At the end of processing, rinse the item with cold water and dry thoroughly.
Step 3
If the surface of the object is heavily contaminated with oxides, prepare the following composition. For 1 liter of water, take 10 g of potassium dichromate and 20 ml of concentrated sulfuric acid. Pour the solution into a glass vessel not to the top (taking into account the volume of the object). Dip the object into the solution and observe the process of dissolution of the oxides.
Step 4
As soon as areas of clean metal surface appear, immediately remove the item and place it in a solution of ammonia to neutralize the acid. Then rinse the product with water and dry thoroughly. The process with sulfuric acid and potassium dichromate requires some care and skill to avoid damaging the metal.
Step 5
After cleaning the bronze, it is advisable to wax its surface. This can be done with wax and a rag or an alcohol solution of wax or paraffin. This treatment will protect the surface of the object from oxidation.
