An icon is one of the greatest works of art, being a sacredly preserved family heirloom.
A believer must have images of saints in his home. They guard the house and protect its inhabitants.
For most people, an icon is a family treasure that is carefully preserved and then passed on to children. Many images may turn out to be very old; they require the right attitude, both emotionally and materially.
Preparing for cleaning
The preparatory process when cleaning brass from oxide at home allows you to avoid serious problems in the future. The features of this stage are the following:
- To begin with, it is recommended to determine whether the alloy consists only of brass, or whether the composition includes other materials. As a rule, a magnet is used for this, since it is attracted to such an alloy.
- Cleaning brass at home begins with assessing the cost of the product and determining its age. Experts do not recommend treating antique items at home, as patina accumulates on it. This layer protects the alloy from various negative factors. An exception is the case when brass loses its attractiveness due to its roughness.
- Before actually carrying out the work, you should wash the treated area from various contaminants using a regular detergent or soap solution. It is recommended to immerse a brass item for 20 minutes, after which mechanical treatment is carried out using a brush. In most cases, this is quite enough for high-quality preparation of the workpiece.
Brass before and after cleaning from oxide
After completing the preparation of brass for cleaning at home, you can begin to carry out such work directly.
For this purpose, a variety of substances and technologies can be used, all of them are characterized by their own specific characteristics.
Common problems
It would seem that keeping sacred relics at home is very simple and nothing will happen to them, but this is not so. A hot or humid indoor climate can damage icons. Following gradual corrosion, the image of God or other saints will deteriorate, and the family value will fall into disrepair. Therefore, it is important not only to pray before the face, but also to properly care for it.
Common problems:
- in an excessively hot place, the plywood on which the image is written may become distorted;
- growing layers of dust;
- candles next to the icon can smoke it;
- cracking and falling off of the paint coating;
- High humidity can cause mold and mildew to appear.
Minor damage to the relic can be repaired with your own hands at home. But the peeling paint and deformation of the plywood are difficult to correct, so special restoration will be required in the church.
Cleaning process
When considering how to clean brass at home, you need to take into account that the features of the procedure largely depend on the chosen technology and substances. Among the general features, we note the following points:
- The final result depends on the correctness of the preparatory stage. This is due to the fact that too large a layer of pollutants leads to a decrease in the effectiveness of the technique used.
- A product for cleaning brass at home can have very different recommendations for use, it all depends on the chemical composition and some other points.
- When processing antique substances, it is recommended to use safer methods. This is because the surface of antique brass items can be damaged.
Today, brass can be cleaned at home using a variety of cleaning agents. An example is oxalic acid and acetone. In addition, there are also traditional methods, many of them are safe and quite effective.
Oxalic acid
Often, various acids are purchased for the task in question, for example, oxalic acid. Such substances can have a highly aggressive effect on the alloy. When using oxalic acid, you can use two methods to eliminate the oxide:
- The brass is coated with acid and left in this state for 5 minutes. When a chemical reaction occurs, a black coating often appears, which is easily washed off with water and a brush.
- It is recommended to carry out work only when using protective equipment. This is due to the fact that oxalic acid can have a negative effect on the skin.
- The surface should be cleaned carefully, since strong mechanical impact will damage such an alloy.
A wide variety of products can be treated with acid. After cleaning at home, you should rinse the product with running water.
You can find two versions of oxalic acid on sale:
- Special gel with added acid. This design option is ideal for cleaning stains at home, but not long-term stains. An interesting fact is that oxalic acid is included in a wide variety of detergents, as it copes well with various contaminants. After cleaning with the gel at home, it is recommended to apply baking soda to the surface, then rinse off all components with clean water. The good thing about the gel is that it is easy enough to apply to the surface and distribute evenly.
- Pure oxalic acid is also commercially available. Recommendations for dilution are as follows: per liter of liquid there are about 20 grams of the composition. The product is soaked in the resulting solution, after which the brass is cleaned with a brush. Work should be carried out exclusively with gloves and a respirator, since acid has a negative effect on human health.
Oxalic Acid Cleaner
Unlike acetic or citric acid, this one cannot have a negative effect on brass.
Acetone
Among the most common effective means that can clean brass is acetone. A similar substance is sold in a variety of specialized stores. Among the features of cleaning with acetone at home, the following points can be noted:
- To begin with, the brass is thoroughly wiped with a swab to remove contaminants, after which it is moistened with acetone and the procedure is repeated.
- If the product is heavily soiled, the brass is treated in a solution of water, salt and vinegar. You can increase the efficiency of the process by bringing the solution to a boil.
- Boiling is carried out for 3-4 hours. If necessary, water is added to the selected container from time to time as it boils away.
Cleaning brass with acetone
When working with acetone, you need to be careful, as this substance should not come into contact with exposed skin or eyes.
Toothpaste
You can clean brass at home using a toothbrush and toothpaste. Recommendations for carrying out such a procedure are as follows:
- To soften old stains, wash the surface with soapy water. In some cases, the product is soaked for several hours.
- Toothpaste should be applied to problem areas. After this, the stains are wiped off sequentially.
- When using a toothbrush, even hard-to-reach areas are treated. In addition, a soft cloth is used.
Using toothpaste can scrub off fairly caustic stains. At the same time, the cost of the procedure is quite low, since toothpaste is inexpensive.
Acetic and citric acid
Among the traditional methods, the use of vinegar and citric acid should be noted. Both cleaning agents are highly effective in cleaning oxide from brass at home if you follow basic recommendations. Vinegar is used taking into account the recommendations below:
- The vinegar mixture is made by combining flour, water and table vinegar. The recommended concentration is 9%.
- All components are mixed together to obtain a homogeneous mixture. After this, all brass is coated.
- It takes some time for the applied composition to dry. Vinegar eats away even large stains. Flour is added to the composition as an absorbent reagent.
After the applied composition has dried, you can begin to remove it. You can use a soft cloth for this. If not all stains have been removed, the procedure can be repeated.
When considering how to clean brass at home, you should pay attention to citric acid, which is mixed with salt. A brass object is coated with a similar composition, after which the brass is washed.
Sandpaper
In some cases, due to severe contamination, it is necessary to use sandpaper. It is made using abrasives of various grain sizes. It is recommended to treat a contaminated brass item with the finest grain sandpaper. Among the features of cleaning with such material at home, we note the following points:
- Too much grit will cause scratches. That is why you should carefully select consumables.
- The desired result can only be achieved by moving the skin frequently. To do this, use a variety of devices designed for grinding brass and other similar alloys.
- In some cases, to increase the effectiveness of the procedure, special pastes are added, which can be purchased in a specialized store.
Sanding block
You can clean caustic and large stains with sandpaper at home. Mechanical processing increases cleaning efficiency.
Soap solution
A solution consisting of water and soap can be used on a wide variety of brass products. The recommendations are as follows:
- The water is heating up.
- The soap concentration should be quite high. As a rule, laundry soap is added to the water, but other cleaning products can be used.
- It is recommended to keep brass in such a solution for no more than ten minutes. This recommendation is due to the fact that warm water heats the alloy, and after cooling the varnish peels off. Applying protective varnish to brass yourself is quite difficult.
- Brass should be washed using a soft cloth and napkin. Abrasive materials should be used carefully as they may cause deep scratches.
Preparation of soap solution
When cleaning in soapy water, you need to treat even hard-to-reach places, for which you use a brush. It allows you to process hard-to-reach places. It is recommended to choose a version with soft bristles that will not lead to the formation of defects. The final stage, as a rule, consists of polishing, for which special cleaning agents and rags are used.
Salt
Often, salt is used during the procedure in question as an additional ingredient in the preparation of a mixture for cleaning brass plaque at home. An example is mixing vinegar and table salt. In this case, the procedure has the following features:
- The product is washed with clean water and then wiped dry.
- Salt and vinegar are mixed together, after which flour is added.
- The mixture must be homogeneous, otherwise the effectiveness of the mixture is significantly reduced.
- The substance is evenly distributed and rubbed with a soft cloth.
- The cleaning agent should remain on the product for several hours.
After keeping the brass for the required amount of time, you need to wash off the composition from the surface. If the stains were not removed the first time, the procedure can be repeated. Vinegar and salt have been used to remove plaque for a long time due to their high efficiency.
Specialized means
You can find special cleaning products on store shelves. They are characterized by high efficiency of application. Among the recommendations for the use of special polishes, we note the following points:
- Cleaning of oxide at home should only be carried out using personal protective equipment. This is due to the fact that such substances are highly aggressive and can cause a burn if they come into contact with the skin.
- More attention needs to be paid to choosing the most suitable product. This is because the wrong chemical will damage the brass and the item will be ruined.
Various cleaning methods and products should only be used in accordance with the manufacturer's recommendations. The most common cleaning agents are “Delhi” and “Metalin”. They contain up to 20% acid, which allows for high-quality cleaning.
Trilon-B
Among the recommendations for the use of Trilon-B, the following points can be noted:
- A special product is purchased and mixed with water in a ratio of 1:10.
- A small product is placed in the prepared solution and kept for a long period (selected depending on the degree of contamination).
- After soaking the brass in a special solution, it is washed under waste water and cleaned with a cloth.
Often, the product in question is used to clean coins and other small items. In addition, ammonia can be used. Among the recommendations for its use we note:
- Ammonia is poured into a special container.
- The product being processed is completely immersed in alcohol and then kept in it for some time.
- You need to work with ammonia using tweezers; contact with skin or textiles is not allowed.
- After keeping the product in the solution for a long period, you can remove it and rinse it with running water.
After drying there should be no residue. In addition, after using a bath of ammonia, you can carry out mechanical cleaning using special materials intended for polishing. At this stage of the work you should be careful, as careless actions can lead to scratches.
Paste GOI
In some cases, GOI paste can be used. It is not of great value, but is easy to use at home. In the manufacture of such a paste, chromium oxide is used, which can have an effect on various pollutants.
The paste must be used according to the manufacturer's instructions, since failure to follow the operating instructions can damage the brass surface.
Acetone
- Using soap. Soap solution removes soot well. But frequent use can lead to the face being partially or completely erased. As a result, the most valuable icons are lost.
- The yolk of a chicken egg, boiled chilled water, turpentine, and alcohol in a ratio of 1:5:2:2 will help get rid of soot. Mix the composition well and apply with a soft brush or cotton swab. Then wipe the paint layer with a dry cloth.
- How to properly restore an icon yourself if the paint layer begins to peel off? To do this, use 1 chicken egg yolk and 5 parts water. The emulsion is applied to the damaged areas and dried for 1 hour. This manipulation is repeated several times. Then you need to moisten the damaged areas with the same solution and press them against the board.
- Vegetable oil will help return the color to the icon. In the old days they used olive oil. They wipe the face with it once a month. Apply a thin layer.
Aerator key.
Removing varnish
In some cases, damage to the varnish causes the material underneath to become darker and lose its color. It is removed in a variety of ways, the choice is made depending on the characteristics of the alloy. You can remove the topcoat as follows:
- The varnish is removed with hot water. When the surface is exposed to high temperatures, the metal begins to expand; after cooling, the varnish comes off.
- The product to be treated can be placed in boiling water, but for no more than 3 minutes.
- If home methods do not help with removing varnish, it is recommended to purchase special solvents. They are found on sale in special stores.
- If the varnish layer is too thick, remove it with an abrasive material. The movement should be made in one direction and without strong pressure. This recommendation is due to the fact that too much mechanical stress can lead to deep scratches.
After removing the varnish, the brass is cleaned of plaque and dirt. For this, various special means and folk methods can be used.
Storage rules
Proper care will ensure long-term storage of family value. Therefore, in order to avoid having to restore the paintwork and wipe off soot from the icon, it is recommended to store relics only in the appropriate places and follow simple rules. Recommendations from experts on caring for icons:
- Lighted candles should be placed only at a distance of 20 cm from the image.
- As a rule, icons are installed in the corners of the room and far from radiators, window openings, and so on. In this case, mold will not occur, since air circulation will be constant.
- All churches have stained glass windows because the sun's rays slowly destroy the icons. Therefore, family valuables should be kept away from windows.
- Also, there must be a minimum concentration of moisture in the house or apartment. If it is high, then after a while a fungus will appear on the face.
- The paint coating on the front side cannot be treated with alcohol varnish.
- Lye and washing powders are not suitable for washing church supplies, especially for icons.
- Washing with water can lead to the destruction of the icon. In this case, the paintwork will appear with whitish spots. Such care will not lead to anything good.
- Dust is removed with a brush or soft cloth.
- If there are frequent temperature changes in the room where the icons are located, the paint on the icon will crack and the wood will swell. Loss of original appearance is guaranteed. Therefore, it is better to install the icons in another room or fix the problem.
- Flies crawling along the surface of the face leave “spots” (bulges) on it. They cannot be scraped off because they are partially absorbed into the paint layer and can fly off with the paint during mechanical cleaning. In this situation, only a restorer can help.
By following simple rules, the icon can be preserved not only by children, but also by grandchildren and great-grandchildren. If small cracks have formed in the image, you should urgently go to a church restorer or other experienced specialist. To get detailed advice, you should visit a church and get advice from experienced people. One of the duties of true believers is not only keeping the commandments, but also carefully storing icons and other sacred church utensils.
How to clean severe darkening?
Severe darkening can be cleaned using a variety of materials. The combination of lemon juice and a pinch of boiled salt is highly effective. Among the features of this method, we note the following points:
- Before cleaning, the surface is washed with clean water and then wiped with a dry cloth.
- If the surface layer is varnish, you will have to remove it. This is due to the fact that during long-term use of brass, plaque can form under the varnish.
- After preparing the product, you can begin cleaning. Lemon juice is mixed with table salt, thereby increasing the effectiveness of the resulting mixture.
Polished brass
A surface can only be cleaned until it shines using a combination of several methods. An example is that after applying the mixture, the surface is cleaned and treated with soft sandpaper. It is not recommended to use an abrasive that is too coarse, as this leads to deep scratches.
Mold and mildew removal
The sacred image on the tree can be destroyed due to mold, which spreads very quickly. If mold has formed on the front of the icon, in order to avoid damage to the face, you should take the icon to a restorer. Removing mold in a visible place yourself is very difficult and can do more harm than good.
If the fungus has spread to the back of the heirloom, you can remove it yourself. You will need a brush whose bristles are made of nylon.
How to remove mold from wooden surfaces of icons:
- You need a piece of cotton wool and hydrogen peroxide. The material is dipped into the solution and applied to the damaged area. If the procedure helps, the area is treated again.
- Only vinegar and soda will remove a large amount of mold. It is not recommended to use this method very often, since this is an emergency measure for cleaning the surface from fungus and mold. The infected area of the icon is wiped with a piece of cotton wool previously soaked in vinegar.
- This method involves wetting baking soda, making a paste of it, and applying it to the damaged part of the heirloom. Wait for some time, and then the applied paste is removed with a dry cloth.
Under no circumstances should you wash icons with water, otherwise it will seep into more difficult places, and therefore, within a short period of time, the face and paint coating will be damaged.
What should you not do during the procedure?
Recommendations for processing a brass product are related to its purpose. An example is the following points:
- Costume jewelry, figurines, and other decorations should not be treated with abrasive material. This is due to the fact that a fairly large number of scratches appear on the surface, which are difficult to get rid of.
- It is worth considering that citric acid is highly effective, but can seriously damage the treated coating. That is why such a substance is used taking into account all precautions.
- Brass is susceptible to scratches. That is why you need to be careful when carrying out work.
Result of careless cleaning
In addition, when using special cleaning products, you must follow the operating instructions. Some substances are highly aggressive.
What not to do and use
It is not recommended to use products with hard abrasive particles or thick fabrics for cleaning. Before cleaning, you need to rinse things in a soapy solution to wash away dust, which may also contain abrasives. Do not use brushes with hard bristles or rough fabrics. Such things can leave scratches on brass products, making them look less attractive.
Do you believe in the benefits of visiting cosmetologists?
Not really
It is not recommended to wash brass utensils, as well as jewelry and figurines in the dishwasher, as they will quickly lose their presentable appearance and begin to darken. Do not leave the caustic composition on the product for a long time. You should constantly check how the brass has been cleaned and whether the product should be washed off.
You cannot use acetic, citric and hydrochloric acid in high concentrations, as they can damage the item. Also, you should not use alkaline-based products, since in this case the darkening will only worsen as the copper will react with oxidation with the alkali.
Do not wash varnished items in hot water, as this will remove the entire coating. However, they should not be polished either. Instead, it is recommended to remove dirt using a soap solution.
Precautionary measures
When carrying out the work in question, it is recommended to pay attention to several recommendations. Let's call the main ones:
- A waterproof film is placed in the treatment area.
- When working you need to use special clothing.
- It is recommended to carry out cleaning with gloves. This is due not only to the fact that the substance can have a negative effect on the skin, but nails can cause scratches.
- It is necessary to carefully study the scope of application of the chosen product, whether it is recommended to use it in a particular case.
- It is recommended that before starting work, you determine what substances are included in the alloy. If the brass contains impurities, the cleaning procedure may be slightly different.
Experts do not recommend cleaning old items. Restoration should be carried out exclusively by a professional, since if a mistake is made, the surface may be damaged.
Traditional methods
- The aerator consists of a rubber gasket, a mesh filter and a clamp with which the structure is attached to the tap. This fastener is unscrewed with a key for aerators. This must be done carefully, since at this stage the filter may break, especially if it is made of plastic. If there is no special key, this can be done using pliers, having first wrapped the aerator in a piece of cloth so as not to damage the surface.
To preserve the relic in its pristine beauty for a long time, follow simple rules:
What to do if there is no result?
If, after cleaning with improvised materials, the result does not live up to expectations, then you can remove the coating and reapply the brass. The procedure is carried out taking into account the following recommendations:
- To begin with, prepare the place where the work will be carried out. To do this, the base is covered with film.
- The surface layer is removed using a special liquid. It is worth considering that such liquids can be easily flammable.
- The second step is to polish the brass. To do this, a special polish must be used, which is rubbed into the surface. Polishing can be carried out after cleaning using various materials.
- After this, the surface is varnished. The substance should be applied evenly; a brush or cotton swabs can be used for this.
After completing the previous operation, the surface is wiped with almost any cloth. In order to eliminate the possibility of fingerprints appearing on the surface, work should be carried out with cotton gloves. By infrequently wiping the surface and removing dust, you can eliminate the possibility of rapid plaque formation.
In conclusion, we note that each case is unique in its own way. That is why you need to carefully select the most suitable cleaning method.
For example, products with complex shapes are often treated with a brush; in some cases, the use of acid is prohibited, as it can damage the brass.
What is brass and where is it used?
Brass is an alloy of copper and zinc. The material contains elements such as manganese, tin, aluminum and lead particles, which change the characteristics and color shades of the metal. Zinc was discovered in the 16th century, but brass was discovered in ancient times. The metal was obtained by melting copper and zinc-containing ore.
When making the alloy, up to 30% zinc is added to the composition, but to improve technical characteristics, up to 50% metal is added. Brass practically does not wear out and is used in the manufacture of automotive spare parts, serpentine elements, heating radiators, as well as stamped parts and various accessories. Alloy brass is used for the production of aircraft, ships, watch parts and main pipes.
Using tombak (an alloy with a zinc content of no more than 10%) insignia is made. To protect elements from corrosion, cast brass is used. It is used to manufacture bearings, shut-off valves, and separators. Thanks to the properties of the alloy, compasses and heating radiators are produced. Cleaning of brass is carried out without the use of additional equipment and special products.
The metal is used in jewelry in the manufacture of costume jewelry, as well as counterfeit gold jewelry. The alloy content of up to 15% zinc and the addition of 5% aluminum allows you to obtain a material similar to precious. This condition is used when making frames for icons, as well as other items in churches.
Cleaning icons made of different metals
Repairing an icon is not an easy task, but it is doable. To minimize the risk of new damage, home restoration should be carried out with the utmost care.
How to clean copper icons, as well as silver, gold and bronze:
- Tooth powder is great for cleaning copper coins and relics. Copper, gold and silver heirlooms are difficult to clean, especially if they have carved textures. For proper washing, special products are sold that are used to treat jewelry made of all kinds of metals. To clean copper products, use Goya tooth powder or paste.
- To make silver and gold images shine, you need to use alcohol and vodka, previously diluted. Specialists clean the icons with cotton swabs soaked in a solution. To check whether the prepared mixture will harm the relic, it is recommended to coat the area that is almost invisible. If the varnish or paint has not come off, you can safely wipe the product.
- There are combined icons, for example: wood and metal. In this case, barrel tomatoes and cranberries will help. In order not to spoil the image, washing should be done without haste and carefully. First, cranberries and sour tomatoes are applied to the metal, then the dirt begins to come off from the metal surface, and then it is wiped with a dry cloth. The procedure is carried out over and over again until all the dirt is washed away and the metal becomes light.
- The surface of the relic is well cleaned with ammonia. Take a regular brush, which is used by artists, and then the solution is applied to the entire surface of the icon. Its owner must wait some time and wipe the church item with a dry cloth. When finished, use a hairdryer to dry, but at the lowest power, since the flow of hot air can damage the image.
- Gold items are cleaned with acetic and citric acid. If the icons are made of bronze or copper, then the acid is slightly diluted with water. After cleaning the surface, you will need a dry cloth.
Experts categorically do not recommend washing church items with kitchen detergents. You should not use hard powders and so on, since the surface may be scratched during the washing process.
Colorful coating
Images should be washed only with soft cloths: napkins and rags without coarse lint. Church experts advise washing icons in the following ways:
- A soap solution helps remove soot. But often such a procedure is not recommended; repeated wiping can damage the holy face. And this is the most valuable part of the icon.
- There is another recipe that perfectly removes soot: alcohol, egg yolk, turpentine ointment and cool water with a ratio of 2:1:2:5. The mixture is stirred until smooth. A cotton swab is soaked in it and the cleaning procedure is performed. When finished, the solution is wiped off with a dry cloth.
- To prevent paint peeling, you should use a simple recipe: take chicken yolk and boiled chilled water in a ratio of 1 to 5. Apply the mixture to the damaged layer with a cotton swab, wait 60 minutes, and then wipe the coating with a cloth. The process is repeated several times to bring the paint to a shiny state.
- Vegetable oil restores the color of the heirloom. You can use olive oil. It is enough to wipe your face monthly to form a thin protective layer on it. If this does not work, a church restorer will help.
Important! The water used to wash the icons is not poured into the sink or onto the paths. It should only be poured into the garden - in a place where people do not go. If you do otherwise, then, as the clergy say, it is a sin.
If cleaning icons on your own at home scares the owner, then it is better for him to resort to professional services. Incorrect procedures can further damage the coating.
How to clean a brass samovar?
A beautiful samovar turns an ordinary tea party into a celebration. But often dirt appears on the sides and inside. Methods for cleaning them depend on the material of the device.
An alloy of copper and zinc is often used to create samovars due to their strength, aesthetic appearance, and ease of processing. With a long period of operation, old products become dull and become greasy. Household chemicals can ruin it, so you should make formulations from available products:
- A solution of ammonia (1 tsp) and water (1 l) helps.
- Yogurt without additives gently cleanses. It needs to be applied to the device, wait until it dries and rinse off.
- Moisten the samovar with vinegar and add salt. Rub the coating with a cloth dipped in vinegar.
Do not use abrasives on the device. After treatment, the outside should be polished with a dry cloth. It must be left in dry rooms. Excessive humidity causes dark spots to form.
Basic rules for caring for brass products
By following these simple recommendations, you can maintain the shine of brass items and avoid serious contamination:
- If the product is often used at home, try to maintain constant cleanliness . Regularly wipe things with a damp cloth or rinse them under running water.
- After washing, it is better not to leave items to dry naturally. This can cause unsightly cloudy spots to appear on the surface of the metal. Be sure to wipe the products dry with any material, preferably with a natural composition.
- Try not to touch metal with dirty, greasy hands . Fingerprints may not be immediately noticeable, but if you do not adhere to this rule, in the future the marks may become more obvious and will be much more difficult to clean.
- If you wear brass jewelry, we recommend storing it in a closed box and occasionally wiping it with a soft cloth such as velvet or suede. a special cloth for silver objects , which can be easily purchased at a jewelry store, is ideal for cleaning and polishing
- , ammonia-based compounds or other aggressive agents for cleaning
- Caring for a brass chandelier is also easy. Remove dust regularly with a clean, dry cloth. For more intense contamination, wipe the brass elements of the chandelier with soapy water. At the end of the procedure, do not forget to wipe the product dry.
- Brass door handles are the most susceptible to stains. Street dust, dirty hands - all this negatively affects the appearance of the product. In order to avoid heavy contamination and make it easier to care for the metal, it is recommended to coat the surface of the handles with a special varnish . Please note that over time, the varnish may begin to wear off - do not allow this to happen, check regularly and, if necessary, renew the coating layer.
If you follow these rules and inspect your products regularly, you can avoid most problems. If contamination does appear, we recommend the best methods for cleaning brass.