WHY MELBOURNE WATER SPOTS YOUR PAINT
You wash the car, it looks perfect, and an hour later it's covered in little white rings. That's not a bad wash — that's the water itself. Here's what's actually happening to your paint.
WHAT A WATER SPOT ACTUALLY IS
Tap water carries dissolved minerals, mostly calcium and magnesium. When a droplet dries on your panel, the water evaporates but the minerals stay behind as a visible ring.
Left alone in the sun, those minerals bond to the clear coat. The droplet also acts as a lens, concentrating heat into the spot underneath. What starts as a surface deposit you could wipe off becomes an etched crater in the clear coat within days.
WHY IT HAPPENS SO FAST HERE
Melbourne gets strong UV for a city this far south, and our summers swing hot and dry. A panel sitting in direct sun can reach well above air temperature, so droplets flash off fast and leave their minerals concentrated in one place.
Sprinkler overspray is the worst offender we see. Bore and tank water carries far more dissolved mineral than mains water, and a sprinkler that hits the car every morning will etch a bonnet in a matter of weeks.
HOW TO STOP IT
Never let the car air dry. Dry every panel with a clean microfibre towel or a blower before the water has a chance to sit.
Wash in the shade, and wash early or late rather than in the middle of the day. If the panel is too hot to rest your hand on, it is too hot to wash.
Do not park where sprinklers reach. This single change prevents more etching than anything else on this list.
A ceramic coating helps, because water beads tighter and rolls off instead of sitting flat. It is not immunity — a coated car still spots if you let water dry on it — but you get far longer to deal with it.
WHEN IT NEEDS CORRECTING
If the spots wipe away with a detail spray and a towel, they are still sitting on the surface and you have caught them in time.
If you can feel them with a fingertip, or they survive a wash, they have etched into the clear coat. At that point the only fix is machine polishing to level the clear coat back down past the damage.
That is paint correction, and it starts from $590 at our Epping studio. Light spotting often comes out in a single stage. Deep etching on a neglected bonnet can take more.