Register now to get rid of these ads!

Technical Equivalent of Citric Acid for Aluminum

Discussion in 'The Hokey Ass Message Board' started by Reidy, Jul 24, 2021.

  1. Reidy
    Joined: May 13, 2016
    Posts: 177

    Reidy
    Member

    Hello all.

    I first learnt about Citric acid for rust removal from the very knowledgeable people that frequent this site. I am now officially a member of the fan club.

    I was telling a mate about it today and he asked if there was something similar for aluminum. I thought to myself great question, but I don't know the answer.

    So if any HAMBers would like to share their secret brew for cleaning up aluminum castings I would be very grateful.

    Thanks

    Steve from down under
     
    loudbang likes this.
  2. loudbang
    Joined: Jul 23, 2013
    Posts: 37,832

    loudbang
    Member

    Good question. :)
     
  3. And a PLUS if it would help free alum piston and steel pin problem.

    Ben
     
    loudbang likes this.
  4. rusty rocket
    Joined: Oct 30, 2011
    Posts: 4,281

    rusty rocket
    Member

    I never measure the amount of citric I just pour it in give it a mix and soak the parts. I don’t think it matters what metal you use it on. it’s very mild
     
    loudbang likes this.

  5. Bird man
    Joined: Dec 28, 2009
    Posts: 680

    Bird man
    Member
    from Milwaukee

    I have an old bottle of "Aluminum Jelly" around here someplace.
    It is Phosphoric just like for steel.
     
    pitman and loudbang like this.
  6. klleetrucking
    Joined: Nov 3, 2007
    Posts: 76

    klleetrucking
    Member
    from Dalzell,SC

    Depending on what aluminum parts you're wanting to clean I've used Aluminum Brightener, I purchased it from an industrial cleaning supply. It can be mixed with water to the concentration you desire. Like citric acid, it won't cut grease or oil.
    I've used it on the truck and trailer in my avatar many times.
    A quick search shows ZEP products are available in Australia, their stuff is pretty good.
    Note: if it's a dimension sensitive part I'd be very careful.
     
    loudbang likes this.
  7. Tman
    Joined: Mar 2, 2001
    Posts: 34,733

    Tman
    ALLIANCE MEMBER

    Best thing out there for Al is good old Easy Off oven cleaner, not the fancy new safe stuff. The issue is it can work way faster than you can pay attention and etch the aluminum beyond repair. On our Bulk Tankers there is a citric acid etch that can clean them after lime and cement dust makes them look old, the problem is, once you use the process you can never go back. It looks like clean aluminum but the pores are now open and it will always get stained and soiled and need the same wash from there on out.
     
    loudbang and klleetrucking like this.
  8. Hemiman 426
    Joined: Apr 7, 2011
    Posts: 667

    Hemiman 426
    Member
    from Tulsa, Ok.

    Easy Off? Aluminum?... Bad Juju there!! AA lost a multi-million buck 767 Pylon due to someone using it to clean up some hydraulic fluid coking.
     
    loudbang and warbird1 like this.
  9. Tman
    Joined: Mar 2, 2001
    Posts: 34,733

    Tman
    ALLIANCE MEMBER

    As I said, Easy off works but can goo off too quick. We have been using it to remove anodization since the 70s on BMX components. Best to spray some on and do some quick tests instead of letting it go to long and wrecking the part. Don't doubt 40 to 50 years of real world experience
     
    loudbang likes this.
  10. Hemiman 426
    Joined: Apr 7, 2011
    Posts: 667

    Hemiman 426
    Member
    from Tulsa, Ok.

    32 years at AA. Been around enough aluminum for sure!
     
    loudbang likes this.
  11. Hemiman 426
    Joined: Apr 7, 2011
    Posts: 667

    Hemiman 426
    Member
    from Tulsa, Ok.


    BMX !! My boys did that back in the 90's. Still have a Titanium Black Lite and a GHP hanging in the garage!
     
    Tim and loudbang like this.
  12. Barrelnose pickup
    Joined: Aug 20, 2008
    Posts: 1,321

    Barrelnose pickup
    ALLIANCE MEMBER

    Mag wheel cleaner with Phosphoric acid in it ,
    brush it on, it’ll foam up abit the using when scrubbed with a soft brush and hose it off.
    Good for raw unpolished Ali.
     
    loudbang and jimmy six like this.
  13. MCjim
    Joined: Jun 4, 2006
    Posts: 290

    MCjim
    Member
    from soCal

    Had some stuff I got from the weld shop when I worked for AMF called Alumiprep, it was used to clean aluminum before welding, stuff worked great cleaning my old Harley cast aluminum engine cases.
     
    loudbang likes this.
  14. Gofannon
    Joined: Feb 8, 2007
    Posts: 689

    Gofannon
    Member

    This stuff?
    ALUMIPREP 33 (169315).pdf (solvents.net.au)
     
    loudbang likes this.
  15. MCjim
    Joined: Jun 4, 2006
    Posts: 290

    MCjim
    Member
    from soCal

    loudbang and Gofannon like this.
  16. ottoman
    Joined: May 4, 2008
    Posts: 314

    ottoman
    Member
    from Wisconsin

  17. deathrowdave
    Joined: May 27, 2014
    Posts: 2,664

    deathrowdave
    ALLIANCE MEMBER
    from NKy

    Many many years ago , I kept a few cans of a product called “ Mr. Muscle “ . I would soak a carbon covered , piston in a can of it for an hour or so , and God could not determine it from a new piston . This stuff left the shelves many years ago . I have no idea what it was , but it was the best I ever used .
     
    loudbang likes this.
  18. Not quite the same, but sodium hydroxide will etch aluminum. Sodium hydroxide is the active ingredient in oven cleaner. Sodium hydroxide is also known as lye or caustic soda.
    Sodium hydroxide can clean the aluminum, but the aluminum will be dull. It will ruin a polished finish.
     
    Tman and loudbang like this.
  19. Phillips
    Joined: Oct 26, 2010
    Posts: 1,344

    Phillips
    ALLIANCE MEMBER

    Aircraft Spruce has it, but they don’t recommend its use on cast aluminum. Not sure why, perhaps porosity?
     
    Last edited: Jul 25, 2021
    alanp561 and loudbang like this.
  20. clem
    Joined: Dec 20, 2006
    Posts: 3,432

    clem
    Member

    I wonder whether you could let them soak a little in Gibbsbrand lubricant, might help.
    - I’ve had success with steel bolts in aluminium housing on motor bike parts, but may not be as tough as pistons.
    Perhaps others will comment.
     
    loudbang likes this.
  21. pirate
    Joined: Jun 29, 2006
    Posts: 664

    pirate
    Member
    from Alabama

    Most aluminum cleaners/brighteners contain hydrofluoric or phosphoric acid. Sometimes both. These cleaners brighteners are not all created equal depending on the concentration of the acids. I recently bought some Aluminum Brightener by Quality Chemicals from Amazon. I put some in a pump spray bottle and sprayed it on a bell housing and it immediately started to foam and etched the aluminum to a gray color. That was OK because the etched surface provided a good surface for paint which I intended to do. I bought aluminum cleaner/brightener from one of auto chain stores (O’Reilly’s) and it did very little to the bell housing surface. Most say to dilute with water. The big truck companies use brightner/cleaner to clean/wash bare aluminum semi trailers, fuel tanks, etc but I don’t know the concentration.

    Be aware once aluminum is etched it’s a long path getting it back to a polished surface. A safe aluminum cleaner/brightener can be made by mixing equal parts of vinegar and water then adjusting the ratio as needed. Citric acid would probably work well also but I have never tried it. Aluminum corrodes very easily and the corrosion actually protects the surface when it starts to form. If a polished surface is desired it must be protected by wax, clear coat, etc.
     
    Phillips and pitman like this.
  22. Tman
    Joined: Mar 2, 2001
    Posts: 34,733

    Tman
    ALLIANCE MEMBER

    As I said! But, since you have the degree in metallurgy I defer to your expert analysis!
     
    Phillips likes this.
  23. Pontmerc
    Joined: Jul 13, 2013
    Posts: 131

    Pontmerc
    Member
    from Finland

    Muriatic acid.
    Cleans aluminum like citric cleans steel.
     
  24. Budget36
    Joined: Nov 29, 2014
    Posts: 6,998

    Budget36
    Member

    image.jpg Here’s what we used on my dads Truck after washing it, steps, wheels, fuel tank etc. didn’t harm the paint. We’d use a weed sprayer with water and pour a “gulp” in, shake it up and fine spray it on. It would lightly start to foam white a bit, then we’d rinse it off. If we mixed it to strong it would streak a bit, so we’d go over it again and streaks be gone. Sorry for the angle of the pic, the jug is kinda buried;)
     
  25. Rand Man
    Joined: Aug 23, 2004
    Posts: 3,969

    Rand Man
    Member

    I worked in a few of different manufacturing plants in the past, which did powder coating. I want to say we used the same phosphoric acid was for both steel and Aluminum. I could be wrong, lots of water under the bridge since then.
     
  26. pirate
    Joined: Jun 29, 2006
    Posts: 664

    pirate
    Member
    from Alabama

    Phosphoric Acid when applied to steel/iron forms iron phosphate which is a gray/black coating. It’s an excellent base for adhesion when painting. When zinc and or magnesium salts are added to he phosphoric acid the process is called Parkerizing that is sealed with oil or wax for corrosion prevention. This is the same coating you find on hardware such as socket head screws/bolts.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.