How much adhesion should paint on a bumper have? I have noticed a blister on the front bumper of our C5 today and, whilst it has collected numerous small chips and scratches over the years, that have gone down to the plastic, it has only ever flaked off once before, which was when I first bought it. It will definitely require a repaint to avoid an unsightly patch of black plastic. The car is now five years old. Is this kind of thing inevitable with paint on plastic? Would it be best to get the whole of the bumper done?
Also, there doesn't seem to be any primer coat underneath the top coat. Is this normal nowadays?
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Its difficult to say without seeing your particular bumper but generally speaking the paint should be adhered as well to your plastic bumper as it is to a metal panel. It sounds like your bumper has either had some poor paintwork done to it or it was never very well done at the factory originally.
As for the primer issue, the later paint products don't always require a primer as such. I don't mean that you can spray topcoat straight onto the plastic, but it is not uncommon for an adhesion promoter to be sprayed onto a bumper then the topcoat applied straight onto that. An adhesion promoter is normally clear and not dissimilar to water in its appearance, but you spray it on then wait until it dries, then hit it with the topcoat. That is probably why your bumper looks like it has never had any primer, but rest assured there will have been some other product used to make your paint stick.
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I assume that even light impact would be liable to make the paint flake off though?
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I've had my Bora front bumper's offside edge damaged by a careless unknown driver - the paint was cracked over about four inches but is holding up well after some 12 months.
Hardly seems worth undergoing a repair for what is, after all, a plastic bumper.
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What\'s for you won\'t pass you by
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>>I assume that even light impact would be liable to make the paint flake off though?
The paint shouldn't flake off at all. If you have had a light impact on the bumper then I would expect the paint to scuff or crack but it should not really be flaking off. Flaking is a sign of one thing and that is poor adhesion. It might take a small impact to get that initial crack but that is as far as it should go.
How much is the paint flaking? Is it just a little bit or is it coming off in sheets?
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There is an area about half a square inch, at present. I expect it to come off the next time the car is washed, if not before.
Is this the kind of thing that should be covered by a paintwork warranty?
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I don't think you will have any success trying to chase a warranty claim. They will just turn round and say that it is down to stonechip damage and you can't rely deny that.
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If the paint is flaking then that indicates either poor preparation (bumper surface contaminated or lack of adhesion promoter) or their is insuffucient plasticiser in the paint - making it brittle and prone to flaking/chipping. The paint should stick as well to the bumper as to a metal component.
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I'm sure the surface of my coloured bumpers is part of the bumper material and not paint.
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L\'escargot.
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The car missed its first paintwork and corrosion check, which was due after 4 years, so I will have no joy with a claim on the warranty, I would think. There is a deep scratch just above the paint blister, so no doubt the local dealer would say that it is the cause of the problem and should have been dealt with by now. Personally, I don't see why chips and scratches should lead to blistering and flaking, as bumpers are bound to pick up hundreds of small stone chips over the course of a few years. It is not as though the plastic underneath the paint is subject to corrosion.
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Strangely enough although the front bumper of my Bora drops very low to the ground (it catches on some sleeping policemen) stone chips have been completely absent even after almost 58k.
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What\'s for you won\'t pass you by
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Personally, I don't see why chips and scratches should lead to blistering and flaking, as bumpers are bound to pick up hundreds of small stone chips over the course of a few years. It is not as though the plastic underneath the paint is subject to corrosion.
Moisture finds its way in through the chip / scratch, and then expands & contracts depending on the weather. In summer it's not so bad as the moisture will more than likely evaporate, but in winter it remain there for days and can expand when it freezes, thus lifting more of the paint from the bumpers surface.
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Moisture finds its way in through the chip / scratch, and then expands & contracts depending on the weather. In summer it's not so bad as the moisture will more than likely evaporate, but in winter it remain there for days and can expand when it freezes, thus lifting more of the paint from the bumpers surface.
So, paint is going to come off somewhere, sooner or later then?
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My experience of plastic painted bumpers is that they can be extremely durable. For example a '95 Mitsubishi FTO I look after has got a lot of stone chips on its front bumper - picked up over the last 11 years, but there is no flaking or lifting. They seem pretty durable as regards chips/scratches, the problem usually comes if there is an impact when the bumper flexes but the paint is not flexible enough and so cracks and 'crazes'.
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There is no cracking or crazing in my case, just an area where the paint has lifted, to form a bubble.
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Ever since the earliest days of a particular Porsche model (can't remember which), bumpers have become an integral part of the car and needed to be painted in the identical body colour (whether metallic or non-metallic finish).
Initially and as far as I know still the best system was a tailor-made coating based on polyurethane technology which had both the required hardness, adhesion and flexibility, together with durability to the elements.
Oz (as was)
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I went down to the local Citroen dealer on Tuesday to have the peeling paintwork examined. They don't have a bodyshop, so it was looked at by a chap from a bodywork repair business that they use. His comment was that water had got behind the paintwork because of a stone chip, and that Citroen wouldn't entertain a warranty claim. So I asked how one could be expected to keep the bumper free of stone chips, whilst at the same time keeping water off the car.
The matter was referred back to the dealer who said they would approach Citroen to see what they would, or would not, be prepared to do.
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His comment was that water had got behind the paintwork because of a stone chip.
That sounds like rubbish to me. If the paint was properly adhered to the bumper in the first place, then there's no way water could get behind the paint.
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>> His comment was that water had >> got behind the paintwork because of a stone chip. That sounds like rubbish to me. If the paint was properly adhered to the bumper in the first place, then there's no way water could get behind the paint.
Which is my opinion also. The comment he made completely lacked any logic to me. Stone chips can't be avoided and water on the paintwork can't be avoided. As I pointed out to him, there are plenty of other stone chips on the bumper where the paint is not peeling off.
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I now have an official response from Citroen UK, which is that they will not pay for the bumper to be repainted. They said that all chipped paintwork should be touched up to prevent water from getting behind the paintwork. So, what about the instructions for applying the touch up paint only when the temperature is above 15 degrees C? A bit difficult at this time of the year, when it is also mostly very damp.
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And to repair this properly, you will have to expose a much larger area than currently affected and prepare the underlying 'virgin' bumper accordingly. This leaves it as more than a touch-up and more like a small spra..., no make that a full respray.
I agree with you entirely. Citroen are weasling out of this one.
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It was the Porsche 928 from 1978(?)
What a car!
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Is it really paint? I had a (white) 306 XSi which had black bumpers with some sections which were white. Even just using an ordinary hose during washing it was enough to peel off the white parts. I got the impression that it was a thin plastic film, not paint as we know it.
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L\'escargot.
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There's a hyphen missing from the thread title. Many contemporary cars have what might just as well be paint-on bumpers, providing about as much protection as a coat of paint but costing far, far more to replace.
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It may be that this area of your bumper paint does not have perfect adhesion but you have to be fair to Citroen. Lots can happen to bumpers in five years and you even have that adj scratch as a possible source of the problem.
It may well be that when the scratch was done a less sharp part of whatever pushed very hard on the bumper to break the paint/bumper bond. The paint held up well by not cracking off but over time as mentioned above water and weather have done the damage.
Why not just get in a Mr Chips type person and have it sorted at modest cost?
As a matter of coment I avoid ever buying cars that are painted in the bumper contact area. Bumpers are for bumping not polishing.
M.M
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As a matter of coment I avoid ever buying cars that are painted in the bumper contact area. Bumpers are for bumping not polishing. M.M
But these days you don't get much choice. Most/all cars these days have painted bumpers.
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Quite true... one of many reasons why I choose not to run a these days car. I'm currently changing both our vehicles to last the 2007-2013 period and it is getting harder to meet all our needs... inc black bumper contact points!
M.M
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