Article contributed by Capt. Tom Kenny
Chrome
You do not polish chrome, you clean it. Unlike aluminum and stainless steel, chrome does not oxidize much. It is inert, very hard, and usually thin. People have tried a bunch of polishes, including the expensive ones, and have found nothing that will remove scratches from chrome. You live with a scratch in chrome, or rechrome the part.
If you are very careful not to scratch it, all you have to do is remove the grime and the shiny chrome will be underneath. Use soaps and solvents, but keep abrasives far away from chrome. Be very careful to use clean, soft rags, one embedded metal chip will ruin your day.
Products that could be used are:
- Nevr-Dull
- Stainless Steel
Stainless steel is not 100 percent corrosion resistant. It needs be taken care of. The only way it will be corrosion resistant is when it is clean and in the presence of oxygen.
Manufacturers of some boats are using more aluminum but stainless steel is still the best material in the marine atmosphere. If stainless steel is correctly maintain it will last beyond the life of the boat.
It is a misconception that stainless steel is stainless. Stainless steel will degrade like all other architectural metals. The term "stainless" implies a resistance to staining, rusting and pitting. Stainless steel generally has a higher resistance to the effects of exposure. However, stainless steel performs best when clean. Cleanliness is essential for the optimal resistance to corrosion.
Stainless steel is an alloy of iron that contains more than 10% chromium. Stainless steel resists stains but occasionally dulls or will show oily fingerprints. This steel is noted for its hardness and is used for utensils, tableware, sinks, counter tops, and small appliances. In the process of making it, a little of the chromium in the alloy is used to form the hard oxide coating on the surface. If this is taken off, through corrosion or wear, the steel rusts like regular steel.
Stainless steel has the ability to form its own anti-corrosive coating, through an adherent oxide passive film. This natural resistance only can be accomplished in a clean, contaminant-free and oxygen-present surface. Washing the stainless with fresh-water and a mild cleaner will keep it bright and beautiful. When stainless has a smooth, brightly polished finish, it will be more corrosion resistant. Stainless steel can be cleaned with the following:
- Olive Oil: Rub stainless steel sinks with olive oil to remove streaks.
- Vinegar: To clean and polish stainless steel, simply moisten a cloth with undiluted white or cider vinegar and wipe clean.
- Club Soda: Remove streaks from stainless steel by rubbing with club soda.
Consider these tips for maintaining stainless steel:
- Any cleaner that is safe for glass is usually safe for stainless.
- Remove rust spots as soon as possible with a brass, silver or chrome cleaner. Irreversible pitting will develop under rust that remains on stainless for a long period.
- Never use coarse abrasives like sandpaper or steel wool on stainless. These can actually cause rust.
- Never clean stainless with mineral acids or bleaches.
- Never leave stainless in contact with iron, steel or other metals that cause contamination and lead to rust or corrosion.
Apply standard car wax after cleaning. A car wax will help keep stainless clean and will allow it to breathe. You do not want to put a sealant on stainless. You never want to paint a urethane or polymer to capsulate stainless. It needs to be oxygenated. Rust spots are not a sign of permanent damage and in most cases can be eliminated with any commercial stainless steel cleaner.
Products that could be used are:
Smoothing
If a part is just oxidized and gray, but smooth, skip on down to "Buffing." However, if it is pitted or scratched, it must be smoothed. You cannot polish pits.
Wet-sand the part with #600 wet-dry paper using a little liquid dish soap in the water. Sand for a while, then wipe-off the black residue with mineral spirits and a terrycloth towel and look closely. If you can still see the pits or scratches through the dark, dull gray, you are not done. When you have a uniform, dull gray, you are ready to buff. Do not worry too much about screw recesses and other hard to reach places, they do not show in the finished job if the edges are smooth.
Buffing
The final polish on metal is achieved by buffing it with a rotating wheel that has been loaded with a buffing compound. These compounds are very fine abrasives, usually combined with wax in a bar form. From the coarsest to the finest, they are:
- Emery (gray) - aggressive, usually used on steel.
- Tripoli (brown) - usually used on brass.
- White compound (white) - for fine polishing.
- Jeweler's Rouge (usually pink) - the finest, for a mirror finish.
Many people lean towards using just emery and rouge. Emery is good for a first cut on stainless, or aluminum followed by rouge. Usually you can go directly from wet sanding to rouge.
Buffing is a "feel" thing. Keep the buffing wheel moving and you will see when it is polishing effectively. Wipe-off the black residue with mineral spirits and a terry towel. Different alloys require different compounds, speeds, and pressure. You cannot really hurt anything, so experiment.
Aluminum
Within the aircraft and aluminum RV community there is common agreement that the Rolite product and process is the best for restoring the shine to dull oxidized aluminum. The complete process consists of five steps:
- For surface that have never been polished or have not been polished in many years and show heavy oxidation. Clean the surface of excess dirt, sand, oil residue with soap & water or solvent.
- Start with the Rolite Pre-Polish and the wool pads (# 575). Apply polish by hand in a small 12" x 12" area. Buff on lowest speed setting until polish is gone. Wipe-off the black residue with mineral spirits and a terrycloth towel. Repeat until you get a nice bright shine. The Pre-Polish does most of the work, so spend most of your time with its application.
NOTE - Do not let the black residue remain in cracks and around screw heads for more than 5 to 6 hours or it will be very difficult to remove as it dries very hard. When buffing it is very important keep the pad moving so you do not burn the metal. A burn mark is a deep bluish brown colored haze deep in the metal. The best thing you can do is leave the affected area alone and let it cool then return later to try to buff out the mark. After pre-polishing you will have a deep shine with very noticeable swirl or pad marks which will be removed in the next steps. Pre polishing is sometimes the most difficult step and may take several applications to get the desired results. - Repeat the procedures in step 2 using Rolite metal polish & fiberglass cleaner. After polishing, use mineral spirits to remove as much black residue as possible. The solvent will leave a hazy film on the metal. At this point, it is time to final clean to a brilliant shine.
- Repeat the procedures in steps 2 and 3 this time using Rolite AP300. As before work a small area until you have a mirror finish. Wipe-off the black residue with mineral spirits and a terrycloth towel.
Use a clean soft towel and Windex with vinegar, works great. Spray on and wipe until surface it clean and dry. Hand-rub the haze away leaving the shine. This step must sometimes be performed just to check the quality of the shine and depending on your desire result you may have to polish the area again. - Rolite makes a polish & sealant that helps protect the finish and "seals" the shine. Wipe on a thin coat and hand rubbed off as it hazes dry. It does slightly decrease the shine but it certainly helps in maintaining the shine. To maintain the shine simply use a clean soft towel and the vinegar based glass cleaner.
You will have areas where a big polisher cannot reach. Use a high-speed hand drill with a buffer pad and occasionally a Dremel tool with buff pad around and on window areas and hidden seams and joints. Sometimes, a fingertip and even a Q-tip and a crafts stick with cloth wrapped on it was used both for polishing and cleaning.
Also have spray bottles filled with Mineral Spirits for clean up and a solvent wipe-down. Windex with vinegar applied with a misting spray has also become an invaluable tool for haze removal.