1. Damaging to paint: bird droppings etc.
Not all blessings come from above. Bird droppings and other kinds of animal excrement are corrosive. “And the longer corrosive substances are allowed to work on the car paint, the greater the damage can become,” explains Martin Jaworski, Product Manager BMW ColorSystem.
Equally damaging to car paint is the sticky film that covers cars parked under lime trees in spring. This phenomenon is known as honeydew. It may sound sweet, but it makes drivers bitter, for honeydew is the excrement of aphids. They suck the sap from lime leaves and secrete sticky sugar. This film can burn itself into the paint in direct sunlight.
“Such damage is irreversible and has to be repaired professionally,” warns the paint expert Martin Jaworski. His tip, therefore, is to wash bird droppings or honeydew off as soon as possible.
The same goes for insects. A specialised insect remover will stop the insect remains sticking to the automotive paint and they can then simply be wiped away when the vehicle is washed.
2. Neglect for paint: the commonest error
Those who love their cars wash them at least in weekly intervals. According to Martin Jaworski, failure to provide regular care is the commonest error that car owners make. “If the car paint is looked after properly, it will also be more resistant generally to external influences,” he says. This means expensive repairs with car spray paint or touch up paint can be reduced significantly.
“How often you should wash your car depends on the type of car and how you use it,” says Martin Jaworski. But one thing is clear in the BMW expert’s view: “Frequent washing does no harm as long as you bear a few things in mind”.
3. Lover of paint: the perfect car wash
Some car washes have brushes and some have cloths. One type is not inherently better than the other, says Martin Jaworski. But have the brushes or cloths been made dirty with sand, so that they act like sandpaper and damage the paint surface? For this reason, it is extremely important that the car wash itself should be clean and well maintained. Who would want to walk into a dirty bathroom? You should also take time to have a closer look at the brushes. If the nylon threads are brittle or torn, dirt can gather in them.
And should you follow the wash with a wax? Definitely! “The wax seals the top coat of the car paint and thus protects it against external influences,” the BMW paint expert explains.
And at what intervals should wax treatment be applied?
The expert’s rule of thumb is that as long as rainwater drips off the car paint normally, there is no need for any fresh waxing. However, the weather is also a big factor. If you keep your car in a garage, you protect the wax coat for longer than you would under a carport or in the open.
When using a pressure washer, the motorway principle applies: keep your distance!
Martin Jaworski
Product Manager BMW ColorSystem
4. Paint and a cloth: the right way to wash by hand
Do you prefer to wash your car yourself? You are a model citizen! “Among car lovers, washing by hand is considered the kindest way to do it,” Martin Jaworski observes. The important thing here is to use mild cleaning agents with a low pH value, as well as soft, clean sponges, brushes and cloths.
“When using a pressure washer, the motorway principle applies: keep your distance!,” Martin Jaworski says. This is because if the water pressure is too high, it damages the paint. “In this case, the correct distance between the spray head and the car paint will depend on the individual appliance and model.” As a rule of thumb, if the water jet is painful to your hand, it will also be harmful to the car.
5. Back on the road, shining brightly: polishing
Is your car’s paint no longer as shiny as it was on the first day? Or can you see slight scratches? If so, it is time for a polish. Car polish contains micro-fine abrasives. They gently clean the paint surface without damaging it. The polish simultaneously preserves the freshened paint and protects it against the weather.
6. Touching up the paint: car scratch repair with pen or spray
Is the scratch still visible even after you have polished your car? Then the next step is to touch it up – or rather, to have it touched up. “The best way to carry out the paint repair will always depend on the specific circumstances,” Martin Jaworski says. “For this reason, the car paint repair should be performed by trained specialist staff.”
You may not want to buy a new car straight away just because of a scratch, but your BMW dealer can also still help you to help yourself, in the form of advice as well as paint pens and spray cans. You need just the correct colour code for your vehicle, which on all BMW models you can find, for example, on the identification plate, which is affixed to the B-pillar or inside the engine compartment, depending on the model. But you can also obtain the colour code from your BMW dealer. Paint colours can normally be identified easily from the vehicle identification number.
Matt paints need to be cared for in a totally different way.
Martin Jaworski
Product Manager BMW ColorSystem
7. No sheen: matt paint is a special case
“Matt paints need to be cared for in a totally different way,” Martin Jaworski stresses. For example, polishing is a no-no. This is because the abrasives in polishes remove a matt paint’s distinctive rough surface. Over the long term, the brushes of car washes also have a smoothing effect on matt paint, and wax sealants damage matt paint, too. For this reason, we emphatically recommend washing by hand or pressure washer, with specialised cleaning and care products.
However all other types of automotive paint such as metallic or effect paint, do not need any special treatment. “They have a clear coat layer, which means they are not different from solid paints in the kind of care they need,” Jaworski says. Source: https://www.bmw.com/en/automotive-life/7-tips-on-paint.html