stopping rust

[Paul V]

I have been tarting up the rover and trying to sort out the rusty arches, I ground out the rust till I had good metal, then welded in new metal on the bigger structural holes and used a small amount of filler of the smaller holes toward the top of the arch. I primed the car and left as it was for a week due to the bad weather and then getting a cold. In the 2 weeks I'm already getting rusty coloured staining through the primer. Is they a way of stopping this? is it just the primer doesn't seal the paint work?

edited to add I painted K-rust over the ground metal and also tried to get as much onto the back of the metal as possible.

Edited by Paul V on Friday 16th February 15:53

[grahambell]

Your problem could well be having left the job with primer only, as normal primer tends to be porous so will let water/damp through.

[Paul V]

if that is the only problem I'll just take it back to metal again then primer and paint on the same day.

Cheers

[Roberto Rica]

Short answer - move to a dry planet with no oxygen - but plenty of oil supplies.

[grahambell]

Paul V said:

if that is the only problem I'll just take it back to metal again then primer and paint on the same day.

Cheers

You might also want to consider using etch primer rather than the normal stuff as that should give you more chance of dealing with any unseen surface oxidisation. More expensive of course, but you can get in in aerosols from Halfords or automotive trade factors.

[XKRacer]

Go to the frost website and get yourself some POR15 fantastic stuff don't worry to much about the degreaser but the rust treatment and primer is a must the stuff goes hard as nails I would highly recommend it.

[Paul V]

say you paint over the top like normal paint?

[XKRacer]

Paul V said:

say you paint over the top like normal paint?

Gring off the loose rust then paint straight over!