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posted on April 5th, 2006 at 09:45 AM
do I have to get a bare metal paint job
My bug has a few small rust spots, I think someone has done the rust before. The paint job has crows feet etc and needs redoing. Do I have to go to
the expense of having it taken back to bare metal ( I have been quoted $6000 + $1500 for new window seals etc), or is there a cheaper option?
helbus
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posted on April 5th, 2006 at 11:03 AM
There is no 'cheap' option in this case. If you have crows feet or blisters, you must go to bare metal substrate to have any chance of not having
the cracks return.
Paint on cracks will crack again.
Rust must be cut out and new metal welded in the whole area to have any chance of not returning in the near future. The rust eats from the inside
first, so where it is showing, there may well be areas that are 95% eaten through in the same local area that have not shown yet, and shortly after
repainting they can break through.
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posted on April 5th, 2006 at 11:35 AM
Pete can you use rust proofing instead of replacing the metal as a viable option?
I'm just thinking for an area like the top of a bus that might have scattered surface rust across it once you get under the paint and has a couple of
small areas where it has broken all of the way through. Obviously replacing all of the metal would be out of the question, so what would the options
be once it's down to metal.
Sorry if anyone thinks this is a hijack
helbus
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posted on April 5th, 2006 at 03:52 PM
Sensible question.
If it is surface rust that has arisen from the paint surface being worn thin or broken down, then usually the rust does not go very deep. This is
often what you see on hot dry climate vehicles where the paint has literally burnt off the car after many years in the sun. This can be treated by
removing any loose surface rust and treating with a rust converter/ metal conditioner.
If it is penetration rust which has come from the back of the panel, such as what is seen when you have panels close to each other on a seam. Like
bottoms of doors, bottom of nose panel, roof drip rails. This rust is caused by water and dirt/ organic matter which is acidic and being hidden inside
stays wetter longer. Hence why it rusts right through a lot quicker.
Floor pans rust where mud, dirt and organic matter can stay stuck and retain moisture.
The surface rust by comparison is cleaner and drier more often. In fact the layer of rust on there actually helps protect from further rust to a
degree, as rust doent rust anymore, only the new steel will.
Roof panels also get rust from the inside from condensation forming on the inside of the panel, again the seams copping it the most. Like a bathroom
mirror that steams up at the top first.
posted on April 5th, 2006 at 09:45 AM
