Is it possible to repair finish to exterior aluminum?

[Gunta10]

I wanted to remove some key scratches around the door lock to the trailer. Unfortunately I used the wrong product and wrong buffer and it removed the patina from the area I was polishing. I bought a little bottle of clear coat to protect it.

Now I am wondering if there is a way to return the patina to the spots. Or did the addition of the clear coat prevent that from happening? I am attaching a photo to show the defect.

[ROBERT CROSS]

RAT'S...I've gone to far.

Choose one of these and consider the lesson learned.

POI...if you can feel the blemish with your fingernail, all you can do is make it a little better.

I've used this, using a microfiber cloth with the grain you see on the trailer. Be patient & gentle just as SWMBO likes.

Good Luck...

Bob
🇺🇸

[tominphx]

In the metals business that is known as a "short grain No.4 finish" your best bet would have been a very fine grit flapper wheel on a angle grinder with very light pressure and stroke in direction of the grain. Depending on where you are you may be able to find an architectural metals fabricator that has someone that could take care of that.

Cheers, Tom

[ROBERT CROSS]

Originally Posted by tominphx

In the metals business that is known as a "short grain No.4 finish" your best bet would have been a very fine grit flapper wheel on a angle grinder with very light pressure and stroke in direction of the grain. Depending on where you are you may be able to find an architectural metals fabricator that has someone that could take care of that.

Cheers, Tom

Realize that he has already compromised the clearcoat.

If you want it to disappear, spray with a little automotive clearcoat, and cover with a decal from the above link.
Many have done it...like me have.

Bob
🇺🇸

[rwood]

Be patient & gentle just as SWMBO likes.

Good Luck...

Bob
🇺🇸

"SWMBO"???


Blow me over with a feather!!


Didn't think there were any Rumpole fans left

[ROBERT CROSS]

Originally Posted by rwood

Be patient & gentle just as SWMBO likes.

Good Luck...

Bob
🇺🇸

"SWMBO"???


Blow me over with a feather!!


Didn't think there were any Rumpole fans left

She Who Must Be Obeyed
We do go pretty far back.☮️

Bob
🇺🇸

[LNBright]

Will admit, tho' we watch a lot of Brit TV, I'd not heard of Rumpole, but I have known SWMBO for a very long time (decades ago, I hung out in old Series Land Rover forums, picked it up there, w/o knowing the source).

[FMSports]

I did some PDR today on a 6" scratched area at the back of our Classic. The PDR worked well. Then I used some 2000 grit with water to prep and fill the scratched area. But I had a bit of a high point and I lost the clear in a quarter sized spot. It went glossy and darker than the orignal finish.

It is a clear over fine brushed alum, but to match is going to be crazy difficult.
We use 3M green pads in the shop for a brushed metal finish on alum etc but it didn't work here, and the spot got larger .

I did another PDR fix by a window and I'll just brush in some clear on the scratch.

[tominphx]

Unless you can duplicate a short grain satin finish, you might be better off just living with the scratch and sealing it if it's through the clear coat. Scotch brite on a drum wheel or flapper wheel would be your best bet to match the grain but it will take some practice.

Cheers, Tom

[ROBERT CROSS]

You will only be a 'new owner' for a year or so.
That progression will soften your anxiety and make imperfections, self-induced or accidental, much easier to accept.


“Time will bring to light whatever is hidden; it will cover up and conceal what is now shining in splendor. “
Horace

Pick out a decal you like and cover it... Normalization will occur on its own. (The location is a natural for it)

Sweet Streams...

Bob
🇺🇸

[FMSports]

Yeah, I was not expecting to wet-sand with 2000 paper through the clear into the alum and gloss it up. But because I'm using water and the clear is thin and not great, so here we are.

I have alum sheet in the shop, we've worked with it for years. So now onto a bit of a deep-dive into the science. I thought, well I'll just match some paint since the area is small but that looked bonkers, because of the behaviour over light direction.

The AS fact finish is a stock production alum sheet finish which is a bit grey. In the shop we (discovered) using the 3M green pads gives a nice brushed finish when the factory plate is scratched. But that is a fine long hair type of grain.

I got a good short grain finish going by using a sanding wheel and 150 grit. Smooth out with the 3M cloth, it's not bad but too silvery straight on. Angles it looks good. I need to tone it down somehow. (Google says use bleach!)

I've been doing clear coat for my Beetnik VW van project, so I have clear and spot blender on hand. And polishing gear.

[FMSports]

Ran some trials, it makes sense but complex to figure out.

1. Native Alum texture - I used a small 150 grit drum (Dremel) to get some grain. This is too harsh, so knocking that down with the 3M green cloth is better. The 3M cloth is probably enough to provide the req'd matte alum surface.

2. Color - The alum needs some oxidization vs fresh cut. Fresh cut is too silvery. I applied Oxy Bleach (H2O2) and this was good. It brought the silver into more of a gray tint.

3. Clear coat - I'm using "Scratches Happen" (Amazon) or 2K Spray max clear with a 1K Spray Max spot blender as directed.

Also found this after doing the tests. I let the Qxy sit for an hour but probably should have gone longer:

https://www.youtube.com/watch?v=becvsopdhNg

[FMSports]

Updating spot repair:

1. Native Alum texture ->> The 3M cloth is probably enough to provide the req'd matte alum surface.

2. Color - Oxy is optional, leaving it overnight is probably good enough, to take the fresh cut sheen off.

3. Clear coat : this is the main issue. I think the factory clear is tinted a blue/grey, which is why an "automotive" clear doesn't match, because it's transparent. So to achieve a factory coloring, some matching and mixing is required > then airbrush on.

Shops are having to tint clears for special paint colors. The steps they are going through involve test equipment, test panels and matching cards. Pretty neat stuff.

[maxx92]

Wouldn't a ceramic coating restore all blemishes plus protect it from new ones? Then it might be worth the money...