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Author Topic: Rust on sills  (Read 468 times)

Offline rubdub

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Rust on sills
« on: October 21, 2021, 04:01:32 pm »
Hey lads, so I have a bit of bubbling paint just above my side skirts, hoping not under my side skirts as well..

Here's a pic, small bit like this on either side of the car



First time tackling something like this, so any advice is greatly appreciated!

Planning on taking off the skirts, sanding back the bubbling to see what's there. Hoping it hasn't eaten too far into the metal!
Should I use a rust remover/preventer on the area once it's been stripped back? Would an etch primer be best for an undercoat?

Thanks!

Offline Clarkj93

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Re: Rust on sills
« Reply #1 on: October 21, 2021, 04:18:57 pm »
I've done this recently. Like all rust repair jobs, when you start treating you find more in places you didn't expect! While mine looked pretty nasty when I uncovered it all it was all entirely still just surface rust so no hard-core corrosion to worry about so worth doing but didn't need doing immediately like I initially thought.

I sanded down what I could and left any bits in extremely tight fiddly places and then covered all in por-15 rust converter. Then primed, painted and lacquered on my drive. Not a bad driveway paint attempt but certainly not proffessional outcome, and I got fed up with my knackered side skirts not fitting so now run no skirts at all lol! Mine is function over cosmetics though so doesn't bother me.

It may look bad below and make you worry about yours but remember it's all surface still and I bet you majority of cars on the road even "rust free" ones look this when you peel away a bit of flaking paint or sealer or wheel liners.

Here's some snaps:























Offline rubdub

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Re: Rust on sills
« Reply #2 on: October 21, 2021, 05:10:18 pm »
Ah cheers for that write up, yeah defo just thinking it's just surface rust.. but want to nip it in the bud before it gets any worse. I have an old rover mini which I'm dealing with a whole new front end at the moment.. so I think that's what's putting a fire under me with the golf now  :grin:

You took your wings off as well? Hadn't actually even thought of that!

What did you use to take back the paint? don't know if an angle grinder and flap disc is too handcore for such a tight area...

Offline shail

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Re: Rust on sills
« Reply #3 on: October 21, 2021, 05:14:03 pm »
Mine was very similar to the above photos.  I didn't take off the whole side skirt, just undid the screws on the underside and pulled just the end of the skirt away - saves having to re glue the whole thing.

I also took the wings off, as you'll have rust behind them.

Offline Clarkj93

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Re: Rust on sills
« Reply #4 on: October 21, 2021, 05:22:37 pm »
As said you need to take them off to get full access.

I used metal wire drill bit for most of I think and various sandpaper grades for exposed areas like the sills. Alot of what you see is either the paint had flaked away so just a bit of any old sandpaper will get rid of the flaking paint and also the seam sealer simply peeling off leaving un touched clean metal under neath. And for anything that is not covered in seam sealer or not hidden away then yeah would use some far more fine material to get a good finish.

The metal wire was more than up to the job, would only want something less coarse really as it was a bit much from time to time but it was hidden away areas anyway so just painted over it and no one will know. a angle grinder flap disc may be a bit much unless you have a very steady hand!
« Last Edit: October 21, 2021, 05:24:38 pm by Clarkj93 »

Offline rubdub

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Re: Rust on sills
« Reply #5 on: October 21, 2021, 06:22:05 pm »
Cheers for the advice fellas!

Yeah think I might just loosen the sideskirts and try do it that way with the arches off. I heard they can be a right ball ache to remove old adhesive and refit!

Think I might have some of those little drill brush attachments in the shed as it happens!

  :happy2:

Offline Pudding

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Re: Rust on sills
« Reply #6 on: October 22, 2021, 08:20:48 am »
The sill had actually rusted through on mine, just by the rear wheel.  Seems a common place for them to go, also on the MK6 as well.  And no doubt the MK7 as VW appear to have done nothing to prevent this problem through the years.  My MK4s went there as well  :grin:

Removing the side skirt isn't too bad but removing the old adhesive is a pain.  Get yourself a toffee/caramel wheel from Amazon which makes light work of it.

When it comes to sticking the skirts back on, get this stuff specifically.  Cheaper stuff just comes unstuck soon after.  Don't ask how I know  :grin:

https://www.amazon.co.uk/gp/product/B01DVWCXWG/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

It can be a pain getting the skirts back on, but pay particular attention to the rear arch.  Make sure that end fits flush to the bodywork before pulling the backing tape.  If that end doesn't fit flush, it won't go well.  Hard to explain, but hopefully it will become clear when you do it  :happy2:







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Offline rubdub

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Re: Rust on sills
« Reply #7 on: October 23, 2021, 10:14:04 pm »
Ah cheers for that tip Pudding! Had never thought about one of those wheels, deadly!

Yeah was originally hoping just to peel back the ends where I noticed the bubbling. But now I've noticed some more right in the middle 🤦‍♂️

Offline Pudding

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Re: Rust on sills
« Reply #8 on: October 27, 2021, 01:56:04 pm »
I'm afraid to say, if you see bubbling above the sill cover, it WILL have spread under the paint behind the cover as well.

In hindsight, I would have saved up and let a bodyshop do it.  Mainly because rattle can paint is NOWHERE near as tough as proper bodyshop stuff, and neither is DIY preparation unfortunately, which is key to preventing it coming back.

Thing is though, DIY repairs are fine to eek a few more years out of the old girl but if you want it gone for good, I'd recommend letting the pros do it because it's virtually impossible to get the finish right on that thick rubbery paint VW use.


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Offline rubdub

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Re: Rust on sills
« Reply #9 on: October 27, 2021, 04:37:12 pm »
Totally agree.. and I suppose that is the plan for possibly next year as I've a feeling the arches are starting to go. But  I have an old mini which is cleaning  out my bank account with new panels, welding and paint this year 😂

Offline Pudding

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Re: Rust on sills
« Reply #10 on: October 28, 2021, 11:14:38 am »
Oh dear, British Leyland rust is on a whole different level  :grin:  I had an Allegro eons ago and I could feel that getting lighter every time I drove it  :grin:


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Offline rubdub

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Re: Rust on sills
« Reply #11 on: October 28, 2021, 03:24:14 pm »
Haha.. it's even worse than British Leyland rust.. It's 90's Rover rust!!! 😂