Rustspots on roof of 3/4 year old car

bigmal9, Sep 4, 8:03am
Can any professional Panel Beaters confirm what would be the cause of these ?

r.g.nixon, Sep 4, 8:21am
Easy:
The oxidation reaction of iron and oxygen to form the substance that is commonly called rust occurs according to this equation: 4Fe + 3O2 = 2Fe2O3.

elect70, Sep 4, 8:31am
Result of todays low quality factory paint application , only supposed to last until warranty runs out .

bigmal9, Sep 4, 8:33am
Thanks for the equation.
ok so can I expect so called "stone chips" to cause rust spots on the back section of the roof on a SUV in its 3rd year

budgel, Sep 4, 9:05am
I thought your title meant that the car was 9 months old, silly me!
If they are not stone chips, I would complain to the dealer.
What brand Vehicle?

vtecintegra, Sep 4, 9:07am
I'm guessing it's a Mazda - probably in one of the darker colours.

bigmal9, Sep 4, 9:25am
Yes sorry , I meant after owning the car from new in the 3rd year I discovered the rust spots , I'm no paint expert and have hand washed the car from new regularly , I'm almost certain they are not stone chips as dealer would like me to believe !

oldboyjohn, Sep 4, 9:30am
Any chance they are metal filings from something, maybe a commercial building or industry etc near you, that were sitting on the paint then went rusty?

kazbanz, Sep 4, 10:41am
bigmal-it wont be hard to work out if they are stone chips or not.
Pick one in an unobtrusive place grab some jif or toothpaste and rub away at one of them till its cleaned up. Then look to see if theres a chip of paint missing, if not then has the rust spot gone with rubbing or can you still see a rusty line?
basicly if its had metal filings scattered all over it then that cut should get rid of it. if its a stone chip you will see the bare metal

bigmal9, Sep 4, 11:48am
Its not a commercial vehicle so there should not be any metal filings and am familiar with what stone chips look like as I have a few on the bumper and bonnet , would I be wrong to think they are from manufacturing paint defects ? I am aware of how thin the paint can be on new cars now days but did not expect to have to re paint the roof of our car in its 4th year

kazbanz, Sep 4, 11:50am
bigmal--tell that to the people that parked downwind of the rainbows end rollercoaster repaint or all the similar fiascos.

skull, Sep 4, 12:04pm
Why don't you tell us what the car actually is, some brands/models have been known for similar issues. I had one back in 2004 that had roof paint issues, my mate was a painter and he had seen it before so the dealership repainted the roof after their claims of stone chips fell on my deaf ears.

dutch9, Sep 4, 12:37pm
I am a car groomer and this is often a problem . Cars parked near road sides or railway lines are often worse . Rust fallout from other cars disc brakes and rail tracks and as said commercial fallout . We use a special rust killer to remove or a clay bar .

marte, Sep 4, 1:48pm
Grinding sparks are Death to a windscreen.
They are hot & melt into the glass, then they rust. this expands & chips out the glass, or to remove the steel shaving you have to chip it out of the glass.
This leaves a crater (or a abrasive chunk of metal oxide) that rips wipe blades to shreds in seconds.

It does a similar thing to paint.

Welding sparks do the same thing.

keith190, Sep 4, 4:09pm
We had a Nissan Murano which developed rust on its roof rails at 3 years old.Nissan told me to go away so I did but came back armed with many internet stories of similar problems of that model and they then saw it my way

intrade, Sep 7, 12:33pm
I guarantee you if you have a VW rust is your last problem

intrade, Oct 2, 8:54pm
Good accurate comment