View Full Version : Ideas for cleaning aluminum?
Here's the rear cockpit wall:
https://thefactoryfiveforum.com/attachment.php?attachmentid=102638&d=1550942167
You'll notice some corrosion on the aluminum. I believe it is limescale. (It was dripped on). So far, I have tried the following:
- dish detergent
- acetone
- white vinegar
- lemon juice
What you see in the photo is after all of those attempts. Got any good ideas on what would remove the discoloration/corrosion? I also tried combining acetone with steel wool...
Thanks for your input!
3yearplan
02-23-2019, 12:41 PM
I think Scotchbrite would work. Steel wool might be too fine. Won't this be covered by carpet?
Mike
You might want to try C-L-R. It's available at most grocery stores. It stands for Calcium, Lime, Rust. It's a great cleaner, one that I use all the time on our riding scrubber that gets buildups of dirt, debris, and who knows what else, and it's the only thing that will remove the soilage. You might want to test it out on a scrap piece, but I would bet that there won't be any negative reactions.
Rick
If the aluminum is already corroded then it's also pitted. If you want it shinny you'll need to sand & polish it. That will take a lot of sanding to get past the pitting and stain.
If you want it "clean" use an aluminum cleaner such as made by Sharkhide or Eastwood. But be advised, aluminum cleaners contain hydrofluoric acid (not to be confused with hydrochloric acid) which is about the most dangerous acid you will ever use. It's what is used commercially to clean aluminum and every aluminum beer and beverage can you've ever used has been cleaned with a bath of hydrofluoric acid before it was coated. These cleaners will etch the aluminum down past the stain and if you use a high enough concentration or leave it on long enough it will turn the aluminum a silvery white color. It rinses off and is neutralized with water. This is the stuff you use to etch aluminum before painting or coating it. There is nothing better to clean aluminum -- nothing, period, end of story!
Use proper PPE (personal protective equipment) with this stuff and treat it with the same respect you would explosives, rattle snakes, and outlaw bikers.
JohnK
02-23-2019, 01:19 PM
Nothing to add to the OP's question other than to reinforce the need to be extremely cautious around HF (hydrofluoric acid). HF is commonly used in the semiconductor industry so as an emergency first responder at work I have experience being around it and treating exposure to it. It's nasty stuff. It will not burn your skin. Instead, it will absorb through your skin and begin to attack the calcium in your bones. Exposure, if not treated immediately, involves injecting a thick calcium paste into the bones to neutralize the acid. It's about as fun as it sounds.
I think I'll try the CLR. I have some of that on hand. I didn't try it already because there were some indications that it shouldn't be used on aluminum, but I will check that again. Based on the cautions you mention (NAZ and JohnK), I think I'll leave it as is rather than deal with the Hydrofluoric acid. The side of the part with the corrosion is the back or under side. You'd only see it if you crawl under the car. It's not critical, but I thought I should at least try... thanks for the input!
Robodent
02-23-2019, 02:45 PM
If it was me, I would sand it with some 600 or 800 and then buff and polish. Just like you would polishing a grille.
MPTech
02-23-2019, 03:32 PM
If it's the underside of the car, prep it and spray it with some truck bed liner.
If it's the underside of the car, prep it and spray it with some truck bed liner.
I like this idea. Problem solved. Thanks!
David Hodgkins
02-23-2019, 04:40 PM
I like this idea. Problem solved. Thanks!
Don't forget the outside trunk aluminum and the splash guards while you're at it if you want a uniform blacked-out wheel well.
I did it as part of my refresh:
https://thefactoryfiveforum.com/attachment.php?attachmentid=53796&d=1462886869
https://thefactoryfiveforum.com/attachment.php?attachmentid=53957&d=1463146985
https://thefactoryfiveforum.com/attachment.php?attachmentid=54129&d=1463755894
The effect of blacked-out wheel wells is subtle:
https://thefactoryfiveforum.com/attachment.php?attachmentid=92404&d=1535841269
...but once you start looking for it you'll not be able to look at even the nicest builds (and pics) the same way. Missing details can really start to pop out at you:
http://thefactoryfiveforum.com/attachment.php?attachmentid=50593&d=1455296280
:)
Bedliner is a good idea for your application and if you want to do it yourself look at Raptor. For a panel that is on the underside you can use a roller and get a good effect. Raptor can be rolled or sprayed with their proprietary sprayer. It works great and comes in colors or it can be painted. You can get it from Amazon and other retailers.
Wow! This thread really changed direction! (I like it...) I haven't' researched bed liner much, but it is certainly time to do that. I'll check out Raptor, for certain!