If you’ve ever wondered where swirl marks on paintwork come from, and have never used a mechanical car wash, the answer is they probably come from you.

Okay, so technically it’s not you; rather, it’s the equipment you’re using. And in the case of washing a car, the main culprit for swirl marks and minor scratches is a sponge.

That's because there are sponges, and then there are sponges…

Cheap sponges are your enemy. You may be well intentioned; you may have some costly branded cleaning products on the garage shelves; you may even faithfully follow the two-bucket routine (one for soapy water, the other clean water for rinsing); but if you are using a basic sponge like the one you’ll find sold at any DIY store or petrol station, you will be doing harm to the paintwork.

If you use a cheap sponge, it is likely to drag sand and grit all over the paintwork. Even after rinsing the body with a jet wash and applying a layer of snowfoam before performing a second rinse after another five minutes, dirt will still be clinging to the paint surface and a cheap sponge tends to drag it around.

The hidden danger of a cheap sponge

That’s because a basic sponge has quite a hard, flat surface, relatively speaking, compared to a premium sponge that has been purpose-designed for cleaning a car. This means they press dirt against the surface as you apply pressure to the sponge.

By contrast, a professional-standard car-cleaning sponge is engineered to minimise scratching paint. It may have a top layer with high permeability to absorb cleaning products, as well as a denser middle structure that lets air through, helping create a rich foam. A final layer prevents fluid passing through it, which encourages the soapy water to remain in contact with the car rather than pass through and out of the sponge. Clever stuff, eh?

Premium sponges to look for include the Optimum Big Red sponge, the Soft99, DodoJuice’s Supernatural Wash Sponge and the Kamikaze Collection Hagakure Wash Sponge 2.0.

Mitts are best for washing a car

The alternative is a deep-pile, microfibre wash mitt or a lambswool mitt. These are ideal for cleaning a car because they mould to the contours of a car and, most importantly, have a deep-pile surface which reduces the friction against the paint and helps prevent those swirls and scratches that annoy us car enthusiasts so intensely.

Rinsing the wash mitt regularly during the process in a clean bucket of water is also an essential part of scratch prevention. In fact, at Racing Green Car Storage, we work with three buckets: one for the soapy water, one for rinsing, and the other for washing wheels. (And before you ask, we clean the wheels first, then change the rinse water before starting on the bodywork.)

Wash mitts come in many different suitable types however the ‘gold’ standard is a genuine lambswool mitt. These offer the safest and softest surface when making contact with paintwork. Admittedly, they’re more expensive than a sponge, but for less than £20 you’ll have one of the most important tools of the trade that will help you care for paintwork, trim and glass over the lifetime of the car.

So if you ever wondered where those swirl marks come from, now you know…

If you would like to know more about Racing Green’s services, or arrange for your car to be placed in our care, please speak with a member of the team, on 03330 909722, or email us at enquiries@racinggreencarstorage.co.uk

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