Cleaning & Polishing Your Classic Car

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How do you know whether you’re damaging your car’s paintwork by lovely washing and polishing it? We put these questions and more to some of the industry’s experts – and some of the answers will surprise you

The vast assortment of car shampoos, polishes, waxes and cutting compounds on the market have bamboozled many owners into submission. With so much choice, what are the best methods for preserving paintwork and not destroying it with swirl marks and scratches? To find out the answers, we put such questions and more to industry experts including Dom Colbeck of Dodo Juice and Keith Spencer at Gliptone.

Can you over wash a car?

Dom Colbeck

From a technical perspective, no. Mild detergents and soft wash mitts aren’t going to worry modern clearcoat/paint. But in practice, yes, every time you make contact with paintwork, you may endanger it by (unintentionally) rubbing microscopic contaminants into the finish. These particles can be harder than the paint, and therefore mark it. The swirl marks you see in bright sunshine on dark-coloured cars are often simply from unsympathetic wash regimes. The more you wash a car, the more chance you have of marring the paint.

Even a careful detailer using a good technique will not be able to reduce the chances of wash marring to absolutely zero. So the more you wash, then the more you might mar the paintwork.

Washing once every couple of weeks is about right. More than that could be considered over washing, unless you are a chauffeur, taxi driver etc. The traffic police wash their cars every day, from memory. Maybe watch out for the shinier BMWs on dual carriageways!

Keith Spencer

When it comes to washing your car, people often wonder whether they’re washing too much or too little, but it’s impossible to answer that question based on number of washes. Washing your car too little can cause harsh environmental contaminants to build up and damage your paintwork, but harsh car shampoos and bad cleaning techniques can be just as bad, as they can remove protective coatings and leave swirl marks amongst other issues. You pretty much need to use common sense on this one. Wash your car when it’s dirty, but make sure the products and techniques you use are gentle enough to use regularly. It’s also important to keep a layer of wax on your car at all times to protect your paint, and not just when the sun’s shining – waxing your car in winter is just as important (if not more so!).

Are high-pressure jet washers ok to use on a classic?

Dom Colbeck

Essentially, yes – but you should angle the jet and use it from a sensible distance (at least a couple of feet away) to increase safety. But this only applies if the paint is in good condition. Don’t use a pressure washer close to paint chips, flaking lacquer or vinyl stickers. You can remove damaged, flaking clearcoat with a powerful pressure washer, but not paint that’s in a good state of repair.

Keith Spencer

High powered jet washers are fine to use when rinsing you car, provided you use them on a fan setting and you keep the nozzle at least a couple of feet away from any paintwork. Using a jet washer is a great way to remove abrasive dirt and grit prior to hand washing – reducing the risk of scratches and swirl marks.

Just remember to be gentle. If you find yourself getting angry at a stubborn bit of brake dust, tar, dead bugs or any other contaminant, there’s always an answer that doesn’t involve high pressure water or elbow grease, as this will also remove your paint’s coatings

Is just plain hot water just as good as a normal car shampoo?

Dom Colbeck

No – of course not. Hot water for your shampoo is good to use on a cold day, and hot water generally cleans a little more than cold water.

But a shampoo gives you detergents to break down dirt and lubrication to encapsulate dirt and help prevent wash marring. Water will clean a car, but this will mainly be via the abrasion of the mitt. You will get a car clean with water only, but it will be a slower process and one that is more damaging to the paint (as there is a much higher chance of wash marring). A shampoo makes the job easier and protects the paint a little via lubrication. Avoid washing-up liquid though, as this will contain salt and that is bad news for older paintwork (the salt crystals can expand and contract within the surface of imperfect paint, degrading and cracking it further).

Keith Spencer

Absolutely not! A good car shampoo helps to loosen and dissolve dirt, and more importantly it works as a lubricant to stop particles from scratching the surface of the paint.

Hot water is just… well it’s just hot water! You wouldn’t take a shower with just hot water, so why would you clean your car without the right shampoo? Find a good shampoo that doesn’t remove the wax layer from your paint, but still removes the dirt.

AutoMate Bodywork Shampoo and Meguiar’s Gold Class Shampoo seem to do this quite well. Remember, washing your car is not the same as T-cutting it!

How many times can you polish a car annually without damaging the paintwork?

Dom Colbeck

This entirely depends on how much paint or clearcoat there is, and how much paint or clearcoat is being removed in the polishing session.

If there are 40 microns of clearcoat on a new car, and you are tickling it by hand with a gentle polish, you may remove no more than half a micron in a whole afternoon of intensive hand polishing. So you could polish your car as much as 80 times in a year before striking through the clearcoat layer.

But if your car has just 10 microns of paint or clearcoat left due to previous polishing efforts and you use an aggressive machine polishing process (maybe a wool pad and aggressive compound) that may take 2-3 microns off in one go, you could be into a danger zone just three weekends later.

It is really a case of knowing your paint and knowing the history of your paint. A car with a recent respray may have far more detailing potential than a car with original paint that has degraded and been polished extensively in the past.

We’d suggest machine polishing once or twice a year at most, for most car owners. It is rare to need to polish more than this as the car should only become swirled again due to poor maintenance. Once polished you may theoretically never need to polish the car again…

Keith Spencer

While it’s true that polishing a car too much can damage the paintwork, how much is too much greatly depends on the type of polish used and the amount of abuse your paint is subjected to. Intensive three-step polishing treatments are often thought to be the best treatment for your car, but when used too often, these intensive polishes can damage the paintwork.

Using a mild colour-refreshing polish whenever the paintwork loses its lustre is a great way to bring some shine and clarity back to your paint without stripping too much of its protective layers.

Find a polishing agent that also contains carnauba wax to keep your paint safe. AutoMate Colour Refresh Polish (a Gliptone product) is great for most paint types.

Four times a year is a good rule of thumb, but this also depends on the sort of mileage the car is subjected to and the actual condition of the paint. Simply put, if your car doesn’t need polishing, then don’t polish it!

Is there anything to bear in mind when polishing cellulose or two pack paintwork?

Dom Colbeck

Cellulose paint is obviously highly solvent susceptible, so you should only use polishes and waxes that don’t smell ‘solventy’ or of strong chemicals. If your wax smells nice and fruity rather than of paint stripper, it probably uses a gentle solvent. Polishes can contain strong solvents as well, and also watch out for tar removers. But two pack is generally very robust, although a lot depends on the individual paint type and its application. Some two packs will be harder than OEM finishes.

All vintage cars or those painted with old paints should be treated as having a delicate and sensitive finish, and with this in mind, try and avoid strong chemicals. Water based products or those that simply smell nicer are likely to be kinder than those mass-market products destined for modern clearcoats.

Performance can be formidable with some strong-smelling products – like nano-ceramic paint sealants – but there is a reason why carpet glue smells more than blue tack. The solvents help carry certain ingredients, but those solvents may accidentally attack sensitive finishes.

Keith Spencer

Two pack paint and cellulose paint are quite different paint types, with two pack paint being the modern, more durable paint. However, when it comes to general maintenance polishing, your best bet with either is to use a very gentle polish, preferably one that also contains a high-quality wax. AutoMate Colour Refresh Polish is once again a great choice for removing minor swirl marks and revitalising paintwork for both cellulose and two pack paint and gives you the added peace of mind that you won’t be removing more of your paint or sealant than is needed to remove minor scratches.

For more intensive bodywork needs, you might be better using a cutting compound than an abrasive polish. This is a much more involved task of course, as cellulose paint will eventually wear through to metal, and two pack paint will need resealing once you strip off its sealant.

Polish or hard wax – which would you choose?

Dom Colbeck

Polish and hard wax are two distinct things, not an either/or. Polish is a liquid that abrades the paint surface microscopically to clean it, smooth it and create a shine. A hard wax coats a finish to protect it and adds gloss by filling or hiding the defects in the paint already. So you’d use both. Otherwise the polish isn’t going to protect the paint, and the hard wax will be having to work harder by filling more of the defects. Polish for gloss, wax for protection is a good general rule. If you had to choose in a life or death situation, go for the hard wax if your car is a daily driver left outside as it is then protected. But if it is garaged and doesn’t need protecting as much, a polish will make it nice and shiny for the concours you are entering the following day.

Keith Spencer

As with most bodywork products on the market today, the development of new formulations and compounds has blurred the lines between polishes and hard waxes.

As high-quality waxes are appearing in polishes and abrasives are being added to hard waxes, choosing the right product is much more a matter of the formulation than the “class” of product.

Generally speaking, we think that abrasives should only be used on paintwork when they need to. Using abrasives too often will start to wear through sealants and paintwork one layer at a time, resulting in the premature need for a respray. Waxes are quite the opposite, adding a protective layer over the paint and filling in any micro-abrasions.

For this reason, we prefer to use a polish, followed by a non-abrasive wax when it’s needed and a non-abrasive liquid or spray wax when it’s not.

How should you correctly apply polish?

Dom Colbeck

Machine polishing will always give the best results; machine kits cost from about £100 upwards. This is more consistent, renovates paint faster and gives a better shine. For hand application, forget about going around in circles vs straight lines.

If your technique doesn’t mar the paint, it won’t matter. Use a soft microfibre applicator, a suitably gentle polish for the paint type and a soft, clean microfibre cloth to buff the residue. When working the polish, pressure and coverage are more important – this may be easier to control with circular movements. But the swirls you see in cars are rarely from circular hand polishing techniques. They are from poor washing, usually… and if you used a poor polishing technique using straight movements, the reflection from a radial light source like the sun would still give it a swirly appearance anyway…

Keith Spencer

A good polish shouldn’t be difficult to apply; it just takes a little care and patience. Start with a clean, dry car and try to polish on a day without much wind to avoid particles blowing onto your nice, clean car. To apply the polish, simply pour a small amount at a time on a clean microfibre cloth, working in an anti-clockwise motion, one panel at a time. Allow the polish to dry to a haze (10-15 minutes, depending on conditions) before buffing with a second clean microfibre cloth, this time working in a clockwise motion.

The important thing is to work methodically, taking your time and using a product with mild abrasives. It’s also important to give your car a good wax after polishing, even if using a polish that contains wax.

Since polishing will remove any residual waxes, this restores that vital layer of protection. As with all car bodywork treatments, the proof is in the pudding, but if you keep it simple and follow these steps, you can’t go wrong.

When should a cutting compound be used?

Dom Colbeck

Heavy polishing of deep paint defects means the use of a high cut polish, or ‘cutting compound’. This removes a lot of paint but the finish may need refining after using gentler polishing techniques. Obviously, work your way up to heavier polishes (it is easier to cut twice with gentler polishes than to put paint back!) and use a machine polisher if you have the ability.

These can accelerate cut, reducing time and effort. In a nutshell, you use heavier polishing techniques when milder ones don’t work. But be careful chasing out defects that are too deep. A key scratch may need a respray. Removing paint from the defect and neighbouring area may not help your cause and just be a waste of time and effort.

Keith Spencer

When your paintwork is in dire shape and beyond the help of polishes and waxes, it could be time to go for a cutting compound. However, cutting compounds are fairly powerful abrasives and shouldn’t be used unless it’s the last resort. It’s also important to know the kind of paint you’re working with first, as some more modern paints contain a coating that don’t respond well to cutting compounds. Once a cutting compound is used, your paint will be exposed, so you will need to re-treat the exposed paint with several coats of wax.

Does a clay bar really work and why?

Dom Colbeck

Yes, clay really works. It is effectively a rubbery blob of compound abrasives. It’s like asking whether polish abrasives really work or whether they are simply there to make a lot of dust and thicken up the mixture! Clay shears, abrades and sucks embedded contaminants from the (microscopically uneven) surface of the paint. You should use a clay lube when claying to avoid clay marring and to lubricate the contaminant particles.

Keith Spencer

People often ask this question about clay bars because it’s really quite difficult to prove their effectiveness. The idea behind them is that they remove the dirt that you can’t see, which immediately leads people to think they’re a con.

Despite this, they seem to have been growing in popularity in recent years with a murmur that clay bars are the secret that pro’ detailers have been hiding for so long to get that real showroom shine. To an extent, this is true, but it’s really just one aspect of what a professional actually does to achieve the perfect look.

Getting your car to a professional standard takes a lot of time, a lot of patience and a lot of expensive products/equipment, and of course, the right techniques. If you have all of this at your disposal, then a clay bar is probably worth investing in.

However, if you’re like most of us, you need to weigh up the time and money you are willing to invest with the results you expect to get. There are products out there now that do a fantastic job at cleaning, restoring and waxing your car quickly and affordably without causing damage. With most of their products coming in at around £5, (which is a steal when you look at the ingredients and results) we have found that AutoMate ticks all the right boxes for most car enthusiasts who would rather spend their time enjoying their cars than cleaning them.

Is an orbital polisher worthwhile?

Dom Colbeck

Any machine polisher is worthwhile if you have the patience and ability to use it properly. The results can be superb. An orbital is often just a bit gentler than a rotary when people start out. However, choosing an orbital vs rotary is like going front-wheel drive vs rearwheel drive. Both have their advantages. You can get quickly from A-to-B or even tear up a dragstrip in the right front-wheel drive car. Orbitals may be kinder on delicate paint finishes, so they suit a classic audience.
However, you can still damage paint if you don’t know what you are doing, so learn the basic techniques and theory first.

Keith Spencer

When embarking on any intensive bodywork treatments using abrasives, an orbital polisher can certainly make life a lot easier and save on a lot of elbow grease. For routine treatments, however, we would opt for a liquid or spray wax, a microfibre cloth and some good old-fashioned elbow grease. The main downside with orbital polishers (and it’s a big one) is that a lot can go wrong, so orbital polishers are really only recommended for professional use. Along with it being vital that the proper techniques are used, you also need to be absolutely sure you start with a spotlessly clean car and that no particles can blow onto the bodywork whilst you work. You just have to think, if a grain of sand found its way onto the head of an orbital polisher, it would do a lot more damage than a cloth would!

Are waterless cleaning products ok?

Dom Colbeck

The description is misleading because they are often water-based themselves and they use many cloths in the cleaning process which then have to be washed in – you guessed it – water. So they are not fully waterless despite their name. But they are not a con as they can work for some people for some cars – maybe lightly soiled vehicles or for cars cleaned in areas where there’s a hosepipe ban or no access to outside water. What you will do though, is use a lot of product to clean a car safely and to a high standard. This can be expensive. You may use just 8ml of wax to protect a car in comparison.

They can be quite uneconomic and time-consuming, but they do have a place in the market. If you have a tap outlet, get a pressure washer and two buckets and this will generally be a far better route.

Keith Spencer

When you wash your car, the aim is to remove dirt, particles and harmful contaminants, and water is a fantastic way to wash these away and get them far away from your precious paintwork. Proper car washing techniques involve a thorough pre-spray and using a separate bucket of water to rinse your sponge without contaminating your soap bucket with grit and particles. A waterless cleaning product does sound very convenient and eco-friendly, but the risk of damaging paintwork is just too high. We’d steer clear.

Any advice worth passing on?

Dom Colbeck

The two-bucket method is very valuable; a wash bucket with soapy water in and a rinse bucket to dunk your dirty mitt in. Take fresh mixture from the wash bucket, then rinse clean in the other bucket. Very simple and even two 99p builder’s buckets are going to work adequately. Then it’s merely a case of being ‘contact aware’. Is the mitt, pad, cloth or product I am using going to degrade the paint somehow? If everything is soft and clean, you’ll be safeguarding your paint and getting good results (hopefully). And for classic owners, remember the ‘sniff test’. Some of the solvent-heavy products are best avoided on delicate paints and their smell is a giveaway. Finally, have realistic expectations – some paint simply needs respraying – and always stop detailing when it becomes boring or frustrating. Detail sections of a car at a time.

A tired or unenthusiastic detailer is always going to do more harm than good. Your paint should only be entrusted to someone who cares. Otherwise, you might as well take the car to the local hand car wash and take your chances.

Keith Spencer

Modern car care products are very different from what they used to be, so don’t think that just because a product is more time-consuming to use or more expensive that it’s going to do a better job. Spray waxes, for example, were previously only good for using as a ‘booster’ between more labour-intensive treatments, but with the introduction of organosilicones, manufacturers have been able to produce quick and easy-to-use spray waxes with results that rival the hard waxes.

Manufacturers such as AutoMate have adopted the latest technology to produce quality products that are easy to use and less expensive than most rival brands. We urge you to keep an open mind to new technology, and so long as it doesn’t contain anything that will cause damage, don’t be afraid to try new products and techniques!