Aluminum Cleaning

[-dirt-]

Hi all:

I purchased a used aluminum jack plate (boat part) that is fairly grungy/corroded/nasty.

It came from the factory with a lacquer clear coat finish...

I'd like to clean it up good before installing it on my boat.

Here's what I'm thinking (3-step process)

1) Citristrip or aircraft paint stripper to remove grime and old clear coat

2) Eagle One Mag etching cleaner

3) Mother's Aluminum Polish

Am I on the right track?

Thanks!

 

[drivesitfar]

Dirt: with a handle like that i won't doubt you. i'm kicking your thread up in the hopes of another member either agreeing with your plan or giving you (us) a better one because i own an aluminum trailer that needs a bath.

any pictures of the part to post to show what you are talking about? here's my little aluminum trailer that has a 4 x 8 piece of marine plywood for the floor otherwise all aluminum.

 

[toplessHO]

soda blast?

 

[F124C]

I heard that 'vapour bead blasting' was one of the best ways to clean corroded aluminum, its used afaik a lot on aircraft and motorcycle al. parts, not sure if it's suitable for large parts like trailers.It leaves a nice smooth sheen, not like conventional bead blasting.

(Not an expert so just my 0.02c worth)

Al.

 

[F124C]

soda blast?

Isn't soda alkaline? would this be ok on aluminum? (Idk)

Al.

 

[kramarj]

I have cleaned up some aluminum wheels before and you are on the right track.

I used aircraft stripper to take care of the clear coat. That stuff is nasty, use gloves and safety glasses! I found a hose works good to take it off too. It may also take a couple applications.

From there I sanded the wheels. I don't remember what I started out with, but I worked my way all the way up to 2000 grit. From there I polished.

For a polish, White Diamond is the best I have used. Mothers works okay, but not nearly as good.

I don't know if I would use anything that etches it. I used oven cleaner on something aluminum to clean it and it etched it really bad. It took way longer to polish out.

 

[zkling]

That's not a bad method. Most of the ones I've seen are anodized with a clear coat top.

I've built and welded on many medium sized jack plates. The best stuff to use when cleaning marine aluminum is a solution of hydrofluoric acid. I forget the name but it is a pink solution they sell for pontoon and truck cleaning.

Note that mothers is an abrasive as it contains aluminum oxide. You are going to want to re clear or at least wax the jack plate after you finish polishing otherwise you will just have bare aluminum. Not sure where you are, but I'm going to assume you are primarily fresh water?

I don't know if I would use anything that etches it. I used oven cleaner on something aluminum to clean it and it etched it really bad. It took way longer to polish out.

Most oven cleaners contain sodium hydroxide with eats aluminum.

 

[LS6 Tommy]

For unfinished aluminum I have had very good results with Aluminox from Orison Marketing. Makes aluminum look like new bar stock.

http://www.orisonmarketing.com/aluminox.html

Tommy

 

[-dirt-]

Thanks all.

So it sounds like I'll go with the aircraft stripper for sure first.

I don't care to have a polished/shiny finish -- I just want to get all the gunk and corrosion off, stop it from spreading, and protect it for future use. What do you recommend after the stripper?

I was thinking etching, but I'm not real certain what that will do vs. the stripper??

I was thinking wax would be the final step, for protection...

 

[-dirt-]

Will get a pic up tomorrow. Installing my bro-in-law's lift tonight at his shop.

 

[Riverside]

After getting the clear coat off, you might try "aluminum brightener". It is a mixture of acids which will quickly clean aluminum and remove oxidation. I think the Aluminox, mentioned by LS6 Tommy, is one example. Read the directions carefully. Be sure to work outdoors, or have adequate ventilation. Don't leave it on the aluminum too long.

 

[Kevin54]

Scotch-Brite and WD-40.

 

[Bobf]

I got some aluminum polish from a friend who worked for Northwest airlines years ago called "Met-all". I used it on my 4X10 teardrop trailer I built a couple times a year. Kept the trailer from oxidizing and stayed shiny the 10 years I owned it.

 

[-dirt-]

Mission: Impossible?

 

[toplessHO]

I still say the first step is blasting it
corrosion may be too heavy for soda,may need something a little more abrasive.
then you can switch to a finer grade

 

[Jagmandave]

Glass bead blasting would leave it looking like new.....

 

[-dirt-]

I'm guessing a machine shop would be able to this blasting? What kind of protectant after that?

 

[CGT80]

Glass bead x2

That is pretty nasty. Have you considered having it anodized or clear coated professionally? They probably have a blast cabinet at the coating/plating shop to prep it as well.

My HF blast cabinet with a **** gun and pickup tube, work well with glass bead, but I think I have only done steel with it. If that thing comes apart into flat panels, it will be easier to blast it. Polish or wax will need reapplied. My aluminum tool boxes (on my truck, from delta/job box) are clear coated with an auto or industrial grade of clear coat and that stuff is very tough. They look almost as good as they did 10 years ago.

 

[Fugio]

When we clean nasty aluminum trailers, we use muratic acid from the pool supply house diluted with soap/water and pressure.

 

[nehog]

...d aluminum jack plate (boat part) ...

I've had great results using phosphoric acid for these types of parts.

 

[F124C]

I still think 'vapour bead blasting' will give a better finish than glass bead blasting. Any aircraft guys on here like to comment?

Al.

 

[gtae07]

I still think 'vapour bead blasting' will give a better finish than glass bead blasting. Any aircraft guys on here like to comment?

For a part like this it won't make much of a difference, especially if OP says shiny appearance isn't required.

I would disassemble, blast each part, and blend out remaining rough areas and remaining corrosion with scotchbrite.

The parts could then be anodized, or etched with Alumiprep, Krud Kutter metal etch and prep, or similar. Since it's a boat part, I'd rather anodize.

After that, prime and paint with epoxy; though I suppose if it's anodized you could leave it unpainted. Be careful to avoid any skin or oil contact with the cleaned/anodized parts.

Reassemble and reinstall.

 

[Dennis Leigh Henry]

I've had decent luck with Aluminum Jelly by Loctite and a fairly heavy / non abrasive Scotchbrite type pad.

http://www.loctiteproducts.com/p/s_trmt_alum/directions/Loctite-Aluminum-Jelly.htm

From the material data, this is primarily a phosphoric acid.. mentioned above I believe..

Epoxy / polyurethane would be best to seal it back up with (clear, colored).

****

Instructions from the web:

Application

Apply between 50°F (10°C) and 90°F (32°C). Brush or sponge aluminum cleaner on liberally. Leave on for 5 minutes. An excessive time period may tend to darken some surfaces. Rinse off aluminum cleaner with fresh water. Repeat application, if necessary for heavily corroded areas. Use several 5 minute aluminum cleaner applications rather than one extended application. Rinse after each application.

Cleanup

Water.

 

[-dirt-]

Thanks for all the great ideas guys!

 

[Mike70]

Quote" I've built and welded on many medium sized jack plates. The best stuff to use when cleaning marine aluminum is a solution of hydrofluoric acid. I forget the name but it is a pink solution they sell for pontoon and truck "

I worked in a minerals lab for many years using hydrofluoric acid. It is EXTREMELY dangerous stuff, even very dilute solutions. Please find something other than this. Acetic acid (vinegar) is good. Not sure about muratic (hydrochloric acid). Be careful please.

 

[over40pirate]

Vinegar and water

 

[Lippyp]

I had some Micky T aluminium valve covers soda blasted, it took the old paint off and left a nice smooth but matt finish. I then handed them over to a guy I met at a car meet and they came back polished to a mirror shine. He said they were very easy to polish up.

 

[38Chevy454]

Quote" I've built and welded on many medium sized jack plates. The best stuff to use when cleaning marine aluminum is a solution of hydrofluoric acid. I forget the name but it is a pink solution they sell for pontoon and truck "

I worked in a minerals lab for many years using hydrofluoric acid. It is EXTREMELY dangerous stuff, even very dilute solutions. Please find something other than this. Acetic acid (vinegar) is good. Not sure about muratic (hydrochloric acid). Be careful please.

X2, do not use hydrofluoric acid - very dangerous stuff. Hydrofluoric acid will etch glass, and will go through your skin to the bone. I can only hope the orig post with this suggestion was a mix-up and he meant hydrochloric acid. Hydrochloric acid is commonly available as a diluted acid version that is called muriatic acid, or commonly known as swimming pool acid.

Any acid will help remove the alum oxide on that part, but some mechanical cleaning to help get the bulk of it off would be a good first step.

Acid will not really etch the surface bad, but it will not be polished. Any hydroxide solution will etch the surface, like oven cleaner which is sodium hydroxide.