16 replies to this topic

[mike.]

My cars had a dodgy respray done at somepoint; the signs of it are starting to comes through now.

In the gutters in the roof and on the bottom of the rear window (where water settles) the paint has started to flake quite badly. I reckon this must have been down to very poor prep work - these areas musn't of been perfectly clean when it was sprayed and so water has got under the paint.

So now bits of the paint have started to just flake away. The paint just cracks and flakes away with your fingers if you rub it.

I want to tackle this before i end up needing a full respray. So i was thinking of sanding the area down with some fine wet&dry then using a brush, paint on a very small amount of primer followed by a layer of paint i'v got in a little touch up pot. Is this the best way to prevent the paint from flaking futher without getting to serious and having to have whole areas resprayed?

[Retro_10s]

If water had got under there you would have rust in no time, and by the sounds of it you don't. So it's more likely that the (as you say) the prep wasn't very good... causing a poor adheson bewtween the primer and topcoat, usually due to grease or dust or both.

Problem with touching up, is that what's to say the rest of the gutter wont start flaking in a couple of weeks?... you can't expect the prep to be any better anywhere else.

The brushing method you describe would be fine,... But persoally I think it'd be best to prep and spray the whole gutter...

[mike.]

Yer the paint hasn't flaked all the way back to the metal (yet!) so yeah theres no rust. Now you've said it thats exactly what has happened, the top coat hasn't stuck properly beause of the prep work.

I think i'll use a brush at first and if it starts getting worse i'll go all out and do a proper job.

If i were to spray it properly what would you suggest? Sand down in and around the gutters, treat any rust, then mask up all the roof and top half of the car, spray a few coats of primer on, then top coat, then laquer?

Theres a few signs of filler round the roof so im abit worried i'll just keep finding loads of filler all over if i start getting too serious with the sanding

[G.T.M.]

Forget the paint brush, do it properly first time

If you want some help drop me a PM, I wont go in to writing a bibel about it here

[mike.]

Well i'll be having a blast at it over this week so i'll put some pics up of what i find under the paint. Thanks for the offer - I'll probably be needing alot of advice if i do it properly. How much do you think i'll need to respray? I was thinking in the gutter and about an inch around the gutter at the most.

Got to remember i'v got the rally stripe going down my car which might be tricky to do...

[G.T.M.]

What youv gotta bare in mind is...

Even if you have a perfect match in paint (take your paint code to a paint motorfactors and get them to mix you up an aerosole) you cant just mask off the area and spray it, because youll have a line of colour and lacquer, you need to think about your blending area, how much of the paint youll have to key, because of your stripe youll get away with going right up to that, and useing it as a line (thats rather handy that rally line to be honest beleave it or not it will make it easyer)

Edited by G.T.M., 01 October 2007 - 07:17 PM.

[mike.]

What is keying? I see what you mean about the rally stripe. But i was thinking what would be hard would be spraying the back gutter that goes across the the top of the back window beause i'd have to mask up the stripe and stuff.

[panelbeaterpeter]

Keying means abrading the surface to the paint has something to stick to. Your paint is flaking because the surface hasn't been keyed prior to paint. If you paint directly onto shiny paint, it will peel off very quickly!

[mike.]

Ok so what do i use for keying? Some fine wet and dry?

[panelbeaterpeter]

Yes, either that or scotchbrite is better if there is no damage to the area, and you just need to abrade it. Can be bought in Halfrauds or any bodyshop suppliers.

[mike.]

Right so how much of the paint will i need to redo, i'd be ok with just inside the gutter itself but if i'm going to have to do most of the roof towards the stripe i wouldn't be confident with that at all.

[mike.]

Heres some pics of the flaking bits. Theres definatly filler under the one at the front

What do people reckons going to be the best way to tackle this?

[panelbeaterpeter]

Hmm to fix that properly, you would need to strip it all back to bare metal, re-do the nasty fillerwork, and respray the roof. I appreciate you may not be able to afford that, all I would do until you can, is to get some flame red or whatever colour that is, and brush it over the flaking bits, as it isn't likely to get to a point where it's going to stop flaking, you can keep rubbing back and repainting but in the long run, it would be better for the car and less time consuming to get the whole roof done, at least then you know it's right

Pete

[mike.]

Yeah i know what you mean exactly. I could get the money for it but it'd be a question of whether i'd want to spend all that on - what essencially is a small cosmetic problem.

I think i'll just have to go round and rub down the flakey bits and touch them up for now. If i was going to pay a few hundred to get the roof re-done - in my eyes i may as well get the whole thing re-sprayed because theres minor imperfections like that all over the car really.

So the best way of touching these bits up would be too:

Use some fine wet and dry (probably a mix of 800 and 1200) to take off the paint and get a smooth surface
Clean up the surfae properly
Brush on a coat of grey primer
Followed by a coat of Ford Radient red

Correct?

Is there anyway of preventing the flaking? I was thinking maybe smearing some vaseline around the gutter and where the water settles. Just a thin layer to repel the water?

[panelbeaterpeter]

Yup that would work, I'd personally use 600 grade wet n dry seeing as it's going to be brushed over. 800 and 1200 is only really for when it's going to be sprayed. I'd forget the vaseline idea, I can see where you're coming from, but if you were ever to get the car resprayed it would play havoc with the new paint! I'd just do what you have suggested, and it would will be fine. Just for the information, it would only cost around £100 to get the roof painted.