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VEHICLE OLISHING PAYS

says Alan Smith —Who Reports His Findings on the Qualities of Various Types of Polish and Detergent Shampoo

ALTHOUGH keeping a vehicle clean can be regarded as a desirable end in itself, it is also an economic proposition because of the increase in paint life that results from regular washing and the application of polish. The cost of polishing at intervals of three months, for instance, and of weekly washing, is more than offset if, as is quite likely, the vehicle need not be repainted for three years, instead of two.

Paint wears because of the abrasive action of dust,, the corrosive effect of traffic and industrial fumes, and the oxydizing action of air and rain. Fading, however, is a phenomenon that no amount of washing or polishing can arrest, as i,t is caused by sunlight. Broadly, the more complex the formula of the pigment in the paint, the lower its ability to resist fading.

It is notable that black is the best colour for resisting

fade, because its pigment is simply the element carbon. Other colours with good-fade resistance are cream, grey, orange, yellow, signal red and medium-dark greens. and blues. The colour stability of maroon, beige and light greens and blues, however, is not as lasting.

Polishing is not a practice widely followed among commercial users, probably on account of the time involved. It is not unknown, nevertheless, even among operators whose vehicles work under dirty conditions,

Protection Prime Function

An important point to be realized 13 that the prime function of a polish is to protect a finish; to provide an attractive gloss is only secondary. Therefore those operators whose vehicles work a good deal in dusty areas, such as brick or cement works, are probably pursuing a sound policy in going to the expense of polishing.

The polish manufacturers have recently been turning their attention to the problem of ease of application, and new liquid polishes are notable in that they may quickly be applied either manually or by a simple spray gun. Also, wiping off can be done with a buffer accessory and an electric hand drill.

Although these new products make polishing a more attractive proposition to fleet owners by virtue of the great reduction of time entailed, it remains generally true that the more elbow grease involved in using a polish, the better its protective and lasting qualities.

I have formed this opinion after trying a variety of different brands a18 on my own car, but recognize that although the protection given by an easily applied polish may .be shortlived, this disadvantage is counterbalanced by the short time spent in putting it on. One polish that remained effective for about a fortnight took merely half an hour tia use on my Standard Eight saloon.

Another entailed fairly hard rubbing for an hour and lasted well over a month. A third product occupied a whole Sunday morning in applying, but showed no signs of wearing off after six weeks.

The period over which these polishes were used was more or less consistently rainy, The car is kept

out in the open at night and is washed wiffi a shampoo detergent every week. Each product's lasting properties Were tested equally rigorously.

Some polishes are prepared to appeal to owners who require a quick shine. These consist mainly of light oil and can he detected by their smell. My experience was that the gloss wore off very quickly and the appearance of the car after a few days was dull and unattractive. Whilst the film of oil might well have had good protective properties, it tended to be sticky and hold dust.

At the other end of the scale are the long-lasting polishes of the paste wax type—that is to say, hard wax— usually sold in round flat tins. These are normally marketed in conjunction with cleaners for the preparation of a neglected paint surface.

The cleaner contains a little abrasive and special chemical for the removal of oxydized paint but, being intended for use in conjunction with the polish, leaves little or no protec tion for the finish. Similarly, the polish itself will not clean, a fact which, if not recognized, may lead to disappointment.

It is necessary, if best results are to be obtained, for a paint surface that is not new and has not been particularly well cared for, to be treated with a cleaner. Seen under a microscope, an oxydized and weathered surface is irregular in contour, having a series of indentations that can harbour dirt.

Most of the liquid polishes marketed contain an abrasive or cleaning agent and are, indeed, sold as combined cleaners and polishes. These are the products which have been developed for vehicle owners requiring a polish that lasts a fairly long time and is easy to apply, and are probably the most attractive to commercial-vehicle operators, because mechanical methods can be used for their rapid application. In addition, there is a new liquid cleaner sold in conjunction with a liquid polish, each of which ha" a single function.

A product of the cleaner-polish type is often judged by its powers of removing old paint, this being wrongly thought to indicate an excessive abrasive content. No preparation of this kind, however, can really damage the layers of good paint beneath that which is oxydized, especially if it is applied with light rubbing or simply sprayed on the surface.

Avoiding Abrasions

Other factors cause abrasion in the application of a cleaner-polish and are not always remembered. One is the quality of the cloths used: soft stockingette is advisable. The surface must be free from dirt, for any dust or grit that lies on the surface is abrasive. Nevertheless, taking all due care, I did find that the powers of paint removal of different types of cleaner-polish varied.

Most liquid polishes are of the wax type. Wax is Nature's protective medium. In the ear it prevents the penetration of water into the drum. Wax on the skin of an apple (which can be polished) discourages the penetration of germs from outside, whilst many plants, such as cacti, that grow in arid countries, have wax on their leaves to prevent their water content from escaping.

A problem in the preparation of a wax polish is to obtain a product that will give an even, continuous film with no microscopic pinholes through which water can penetrate. This is

usually overcome by incorporating a .spirit that promotes smooth spreading and dries out when its purpose is fulfilled.

Other additives are included to give hardness to resist abrasion by 'dust, and a small content of silicone is often included, as it is in many paints, to assist the spreading of the polish without smears. A wax finish is inherently water-repellent, as indicated.

Liquid polishes dry fairly quickly after application and leave a whitish haze. This is caused by what is termed the trace element, a fine nonabrasive similar to cosmetic face powder.

Shake the Cloth It shows where the polish has been applied and the operative can therefore not fail to miss wiping odd corners; also it presents a large surface area to the atmosphere which assists drying. When the dried polish is being wiped off, the cloth must be shaken often to get rid of this powder.

In recent years, a polish of the silicone type has become highly popular on account of its ease of application and good cleaning powers. Numbers of fleet owners are using it, applying it by spray to the coachwork, leaving it to dry and then flicking off the trace element with a clean duster. No rubbing is needed.

When applied by spray rather than by cloth, no advantage is taken of the cleaning properties of the polish, the object being merely to spread a protective silicone film over the paintwork.

Ideal for Windows This film is akin to glass in molecular structure, but is not so thick as to be capable of being shattered. It is highly water-repellent and I found the product ideal for cleaning the windows of my car. When it rained, the water beaded rather than form a thin film.

On the paintwork, the polish compares favourably with liquid wax cleaner polishes, particularly as regards time and effort needed to apply it, but its lasting powers did not seem to be as long as those of wax finishes.

This silicone product, however, was the most easily applied and wiped off, and on account of the short time entailed would strongly appeal to fleet operators. One company with a fair-sized fleet of vans wash their vehicles daily and apply the polish once a month.

Some difficulty arises when sur

faces treated with silicone polishes have to be repainted, for the silicones cannot entirely be removed from the metal, even with sanding. Paint will not adhere evenly to a siliconed surface, but there is sold a liquid preparation for washing silicones away. It also shifts old wax and makes the surface perfect for paint treatment.

Whether or not an operator is convinced about the economics of polishing, and, to be frank, there is little concrete evidence upon which to base any judgment on how much can actually be saved, there is another means whereby an efficient operator can reduce painting costs. This is the use of detergents in water used for washing. There is evidence that this arrests oxydizing of the finish.

Value of Detergent One large company have fleets of delivery vehicles based in different towns, and at some depots pure water is used for washing and at others a detergent solution. It has been found that the paintwork of the vehicles cleaned with a detergent is kept in far better condition than that of the others. The vans are washed once a week in summer and three to four times weekly in winter.

The manufacturers of the paint confirmed that the detergent did no harm: normally 1 oz. of detergent is used to a gallon of water, but for greasy patches the strength is increased to 8-10 oz. per gallon.

Nevertheless, many operators are chary of detergents, usually because they have been using an unsuitable

product. Detergents of the household type are too alkaline for cleaning coach paintwork and will eventually damage the finish.

Washing with plain water will remove loose dirt, but as water has no emulsifying and poor suspending power, grease will remain. Paraffin will dissolve grease, but is most difficult to rinse away, because it will not dissolve in the water. Soap is unsatisfactory because it is fatty and leaves streaks.

New products specially for vehicle washing have been introduced since the war and may generically be termed shampoos. They wet the dirt quickly, readily emulsify grease and hold loosened dirt in suspension. Used at normal strength, they will not greatly affect a silicone or goodquality wax finish.

Physical Removal It is always necessary for a detergent shampoo solution to be applied by hand or with a mop, for some patches of dirt need actual physical removal. No amount of highpressure hosing will shift them. The secret of effective washing is, however, thorough rinsing with a copious quantity of water, preferably from a hose. Rinsing must be done before the shampoo water has dried.

Natural and synthetic sponges are excellent for washing vehicles. but linen scrim, such as is used by window cleaners, is probably superior. The dressing has to be removed by washing. Sheepskin mitts can be recommended.

These special shampoos are sold mostly in liquid form and one popular brand is capable of application for general washing purposes in solutions stronger than when used for vehicles. Some operators, however, may find powder detergents easier to dispense than liquid, and there is also one special product sold in jelly form.

If the skin of the hands is sensitive, it would be advisable to wear rubber gloves when washing with a detergent, but many people suffer no ill dermatitic effect through not doing so.