2012 Porsche Cayman S
I have two fairly new black vehicles and was wondering how I remove the spirals in the paint that seems to be prevalent in black-painted cars? – Chester
Swirls occur in all colours; you can just see them better on black.
The degree to which you can correct it depends on how picky you are and the amount of time you are willing to spend. Essentially you have to remove the layer of paint containing the swirls, and re-level the surface – I am talking about microscopic layers here.
Modern clear-coat paints are harder than the older single-stage lacquer and enamel paints used until the 1980s. At that time, manufacturers began using a base-coat/clear-coat system with a protective, hard and glossy clear coat on top of the colour coat. These paints are more resistant to fade and last far longer – because they are much harder.
But that clear coat still scratches and those scratches are highlighted and easier to see because they are on top of a clear coat with a colour beneath. That clear coat is the problem, and the reason conventional hand-polishing methods are not successful. Rubbing compounds and some cleaners can remove the scratches and swirls, but leave their own defects.
The answer is a rotating or oscillating sander –yes, sander, designed specifically for automotive paints. In the hands of an experienced pro, these tools can renew a paint job, removing all but the deepest scratches, let alone minor swirls.
Warning: as the saying goes, do not try this at home. An orbital polisher can cause a great deal of damage if not used properly, burning though the paint or creating the very swirl marls you are trying to remove.
A random orbital polisher with a drive mechanism that will both rotate and oscillate a buffing pad at the same time is the best bet. I use one of these dual-action units made by Porter Cable and, if you put too much pressure on or spend too much time on corners or sharp edges, the pad stops rotating.
If you go this way, you need to pick the proper pad and product to use on the paint – subjects unto themselves. You can try removing the swirls by hand using a product like Meguiar's Ultimate Compound followed by a less aggressive product – any of the top-name cleaners. When using this hand method, be careful to apply even pressure and move continually.
When you are through, remember to apply a protective coat of wax. As I said at the outset, it depends on how much time and effort you are willing to put into the project. Machine polishing for greatest results or by hand to remove some of the swirls.
Lastly, remember that 99 per cent of swirls are created by improper washing. Lots and lots of water before, during and after and uber-clean and soft cloths or mitts.
Oil changes for a stored car
I own a 2006 BMZ Z4 and store it from Nov. 1 to May 1. It has synthetic oil and only requires changing every 24,000 kilometres. Since it sits all winter and I only drive the car for approximately 6,000 kilometres during the summer, should I change the oil every year anyway or could I go maybe every second or third year to change it? – John in Toronto
I, too, owned a 2006 BMW Z4, stored it in winter and drove fewer than 3,000 kilometres in the summer. I changed the oil each year anyway – but then I am a bit over the top in caring for my vehicles.
It is probably okay to go for a couple of years without changes in your situation, especially if you are careful to drive the car long enough each trip to get it up to proper operating temperature so any moisture or other nasty fluids or gasses in the engine can be burned off. If, on the other hand, you drive it for short hops only, say less than 10 kilometres or 15-20 minutes, then it might be advisable to change the oil every year.
Send your automotive maintenance and repair questions to globedrive@globeandmail.com