Aluminium trim staining

[Gbrowncls55]

Hi
I have a 3 month old C200 Cabriolet the Aluminium trim Below the rear window on the boot over has what looks like water staining has anyone else had this and can it be cleaned
Regards
Bill

I had this blotchy look on my cls 4.7 window surrounds. Tried everything but nothing worked. Then by chance i tried the mcguires perfect clear headlamp coating. Just sprayed a bit onto a cloth and wiped it on to the silver window surround trim. Instantly back to new
Amazing. Also worked on my sons bmw black shaddowline trim which had gone the same way.
Cant say how long it lasts but for now it is literally as new.

 

[optimusprime]

Had this on my BMW, on the rear just past back door pilar ,nothing to shift it - only mask it by using WD40 . Dont know why they use this anodised alloy. It will only show up again in a few weekd time

 

[ljs99]

Yet another brushed aluminium staining issue.
Looked like water marks and white milky finish. Mainly on the trim by the boot that the convertible roof closes onto.
This is what I tried (initially in a small area):
1) Meguiars Ultimate Compound - didn’t touch it. When dried, it looked just as bad.
2) T Cut - Same as 1)
3) Magic eraser- Same as 1)
4) WD40 - interesting, this works. I guess it’s masking the stain with a film of oils.
5) GT85 - this also worked. Must be the PTFE coating
6) Gtechniq C2V3 - Same as 1)
7) Meguiars Ultimate Liquid Wax - this was promising, seems that having a coating from the applied product helps. Especially in masking the marks.
8) Peek Metal Polish - OMG, This worked great. It does also clean and protect in one. Once polished off, the marks had gone and looked like new again. Just to be on the safe side, I added a coat of gt85 to help protect all the trim.

All this was applied by hand. The conclusion is, use Peek when marks are visible, After washing use GT85. Don’t use autoglym Polar Wash snow foam (contains traffic film remover).

 

[optimusprime]

Good post .I found WD40 only hids it like you say .

 

[TooFunny]

Not sure about exterior aluminium trim but I've put some Autoglym Magma on a cloth and applied it to stained aluminium interior trim, left it for 5 mins and then cleaned off and it has removed the staining entirely, though to be fair the water spots were fairly light.

 

[ljs99]

Good post .I found WD40 only hids it like you say .

I agree, it just hides it. Some very helpful info on this forum. From my experiments, and previous experience with the black window trims on my SL400, this staining is a real pain. Time will tell if my solution above works long term. With my SL400, my only solution was to get the trims wrapped in black. Fixed the issue. Has lasted over 5 years

Yet another brushed aluminium staining issue.
Looked like water marks and white milky finish. Mainly on the trim by the boot that the convertible roof closes onto.
This is what I tried (initially in a small area):
1) Meguiars Ultimate Compound - didn’t touch it. When dried, it looked just as bad.
2) T Cut - Same as 1)
3) Magic eraser- Same as 1)
4) WD40 - interesting, this works. I guess it’s masking the stain with a film of oils.
5) GT85 - this also worked. Must be the PTFE coating
6) Gtechniq C2V3 - Same as 1)
7) Meguiars Ultimate Liquid Wax - this was promising, seems that having a coating from the applied product helps. Especially in masking the marks.
8) Peek Metal Polish - OMG, This worked great. It does also clean and protect in one. Once polished off, the marks had gone and looked like new again. Just to be on the safe side, I added a coat of gt85 to help protect all the trim.

All this was applied by hand. The conclusion is, use Peek when marks are visible, After washing use GT85. Don’t use autoglym Polar Wash snow foam (contains traffic film remover).

forgot to mention, I also tried 7.5) “bar keepers friend” - Same as 1)

 

[JP79]

if that ally trim is anything like some on some of the american classic cars, there's a way to sort it.

the ally is polished up and then is anodized clear.
the way to remove the clear anodized coating is by (and you have to remove it from the car) spraying oven cleaner on it, leave it for 30min, and then wash it off. sand down with fine grit sand paper. ( I done stages on mine from rough to very fine due to deep stratches)
after that the ally can be polished - you cant polish it when is anodized - but this means using a polishing wheel or give it to a polishing company.
once the ally is polished it will look like chrome, and you can use chrome polish to keep it shiny (like peek. don't use autosol, too harsh).

the above is what I've done on my 65 impala. worked a treat.

 

[DigbyM]

Interesting thread.

I’ve had my 2022 C200 for about 3 weeks now. I’d already turned my nose up at 3 other approved cars as they were too scruffy, mine seemed good. The only thing I regret not spotting before purchase, was the milky window trim. Once I spotted it of course, it bothered me.

I tried various polishes and paint restorers, none worked at all. Other half even questioned why I was heading to the garage with the toothpaste tube from bathroom sink - I evaded the question, but toothpaste didn’t work either.

What has made an enormous difference is to coat the trim with a carnauba wax (I used Collonite 746 from a tin with some dregs in it). Let it dry longer than you’d do on paintwork, say an hour or so. It’s then very hard to remove, but such a small surface area that it doesn’t really matter. After this, trim was vastly improved and remained so day after fay, until I eventually washed the car. At that point the trim had to be waxed again, but easy enough to do any time I want to hide the defect.

If you do try this, open all the windows first, which avoids getting wax on the glass.

 

[ljs99]

Interesting thread.

I’ve had my 2022 C200 for about 3 weeks now. I’d already turned my nose up at 3 other approved cars as they were too scruffy, mine seemed good. The only thing I regret not spotting before purchase, was the milky window trim. Once I spotted it of course, it bothered me.

I tried various polishes and paint restorers, none worked at all. Other half even questioned why I was heading to the garage with the toothpaste tube from bathroom sink - I evaded the question, but toothpaste didn’t work either.

What has made an enormous difference is to coat the trim with a carnauba wax (I used Collonite 746 from a tin with some dregs in it). Let it dry longer than you’d do on paintwork, say an hour or so. It’s then very hard to remove, but such a small surface area that it doesn’t really matter. After this, trim was vastly improved and remained so day after fay, until I eventually washed the car. At that point the trim had to be waxed again, but easy enough to do any time I want to hide the defect.

If you do try this, open all the windows first, which avoids getting wax on the glass.

Good feedback from your tests and observations.

 

[ljs99]

After more research, I’ve read that anodised metal can have an optical effect on the surface of the very hard anodised layer. Engineering tests for this seems to have been researched here https://www.sciencedirect.com/science/article/abs/pii/S1350630708001647

The conclusion being - “The metallographic investigations of the cross section of the transparent anodized layer revealed the presence of pores. That means the stains are an optical effect due..”

as others and I have found, applying a product that adds a layer which coats the surface creating a optical effect (probable filling the pores), thus making the trim look like new.

With my tests, Peek Metal Polish gave fantastic results. Not that I believe it’s the abrasive in the paste providing the solution, it’s the protective layer that peek leaves behind which is fixing the issue. I believe the abrasive clean from Peek metal polish provides a essential ‘Clean’ of the metal before leaving a protective layer attached to the cleaned aluminium.

As quoted from information on Peek - “After use, the polish leaves a gentle, invisible coating on the surface, meaning the metals continue to be protected from moisture and any further tarnishing, whilst preventing dullness and long-term staining”

I believe this optical effect, corrected by a thin film coating, is what we are seeing with WD40, Gt85, Peek and the likes of Wax Polish. Harsh abrasive cutting of the surface is not going to touch the hard aluminium, unless you are intending to completely remove the anodised layer and re-anodised, or leave as polished alu.

I would be interested to hear how this ‘film’ approach works on black anodised trim as I had this issue on my SL400 AMG. I’ve now sold that car. But back when I was looking at the black trim, I ended up having it wrapped in glossy black. Worked a treat, and lasted over 5 years till I sold it.

 

[DigbyM]

I notice Dunelm sell Peek. Which ought to be lucky, as I’ll be in a shopping centre with a Dunelm later.

Unfortunately, with my luck, that particular store’s showing no stock. Think I’ll order some online from Ebay, Amazon, whatever, and give it a try.

 

[ljs99]

I notice Dunelm sell Peek. Which ought to be lucky, as I’ll be in a shopping centre with a Dunelm later.

Unfortunately, with my luck, that particular store’s showing no stock. Think I’ll order some online from Ebay, Amazon, whatever, and give it a try.

Mine was from Amazon..

I notice Dunelm sell Peek. Which ought to be lucky, as I’ll be in a shopping centre with a Dunelm later.

Unfortunately, with my luck, that particular store’s showing no stock. Think I’ll order some online from Ebay, Amazon, whatever, and give it a try.

I purchased Peek from Amazon https://amzn.eu/d/cxAFmWw

 

[Bigdrew]

Had the same problem on one of my car just wrapped it black problem solved

 

[DigbyM]

I’m wondering if anybody has explored whether renewing the window trim is a diy proposition, and ballpark cost for new parts to replace?

Looks to me like most of it might yield to gentle prying, exception being around the door mirrors which I suspect is going to require mirror removal from inside the doors.

 

[ljs99]

for those interested, two pictures attached. First is the milky trim. Second is after applying Peek. As you can see, it resolves the issue. But does need re applying if snow foam goes near it…

 

[OneForTheRoad]

Wondering if Unger rub out, would work ??

 

[Spudgunandy]

I think the trim is anodised aluminium and anything with acid in it will etch the surface. I have the same problem I've tried solvol etc but always comes back

 

[ljs99]

I think the trim is anodised aluminium and anything with acid in it will etch the surface. I have the same problem I've tried solvol etc but always comes back

Agreed.. even new parts will etch. Disappointing that this is the case from a manufacturer. However, as a consumer we need to find ways to make it acceptable. All opinions to help with solutions appreciated