Page 2 of 2 FirstFirst 12
Results 11 to 20 of 20

Thread: Resolving salt corrosion on ratchet straps

  1. #11
    Join Date
    Jan 2006
    Posts
    686

    Default

    I had the same question about the yellowish iridescent color on zinc plating. Yes, it is a chromate coating, but did it really do anything?

    I tested it by taking some identical washers, all of which were zinc plated, but only some had the chromate passivation. To speed up the test, I dunked the parts in dilute HCl. Plain zinc parts started bubbling immediately, and the zinc was gone in a few minutes.

    Passivated parts did nothing for maybe 10 minutes, when they started bubbling slowly. Once they started bubbling, the zinc was gone in a few minutes.

    My conclusion was that the chromate passivation does help, at least in a dilute acid environment.

    Ed
    For just a little more, you can do it yourself!

  2. #12
    Join Date
    Jan 2004
    Location
    Missouri
    Posts
    31,348

    Default

    Your issue is the chloride part of salt. Acids and bases will not help, they will probably attack the chromate, which you do not want.

    Soak them in some water, change water, repeat. Dry off, and go back to normal life. Anything the chloride was gonna do it done did already. The water is so you know you did something. And it will get rid of any remaining salt that has not reacted with anything.

    The Chromate is a thin coating which is quickly removed. Galvanizing is better, and with that, go heavy, or go home. Hot dip is the only thing to consider. Electroplated zinc is a short term coating for "sorta damp" areas. Hot dip has some mass to it, and with galvanizing, only the mass of zinc is of interest, it is a sacrificial coating.
    1601

    Keep eye on ball.
    Hashim Khan

  3. #13
    Join Date
    Jan 2010
    Location
    Germany
    Posts
    6,749

    Default

    Quote Originally Posted by BigMike782 View Post
    Apply some phosphoric acid.
    Have you actually spplied phosphoric acid to anything galvanized? I don't think so because if you had you would know that it will corrode the galvanize coating extremely fast as in minutes. I know that from sandblasting and then spraying phosphoric acid on machines. All the galvanized fittings on hydraulic hoses corroded with in minutes. The fittings are electro galvanized the same as would be the ratcheting strap mechanisms. I could be off but that has been my experience.
    How to become a millionaire: Start out with 10 million and take up machining as a hobby!

  4. #14
    Join Date
    Jan 2006
    Posts
    686

    Default

    Most acids will attack zinc. Phosphoric is fairly strong.

    Ed
    For just a little more, you can do it yourself!

  5. #15
    Join Date
    Oct 2014
    Posts
    445

    Default

    I am finding out that Fluid Film is pretty good stuff to have around. As for stainless ratchet straps, why not make them? Use an old steel one for the pattern. Looks like a good project if you want no rust ratchet straps.

  6. #16
    Join Date
    Aug 2009
    Posts
    6,272

    Default

    Quote Originally Posted by ed_h View Post
    Most acids will attack zinc. Phosphoric is fairly strong.

    Ed
    I've always used muriatic acid to burn zinc off parts that I have to weld.

    JL...

  7. #17
    Join Date
    Jul 2017
    Location
    Buffalo NY USA
    Posts
    343

    Default

    They use salt here in Buffalo..lots of it. At work they bought some new straps and hosed them down with bar and chain lube, the tacky stuff. Messy, but effective.

  8. #18
    Join Date
    Jan 2003
    Location
    On the Oil Coast,USA
    Posts
    19,410

    Default

    I never have issues with ratchet straps rusting....my brother borrows them and never brings them back
    I just need one more tool,just one!

  9. #19
    Join Date
    Jan 2006
    Posts
    686

    Default

    Quote Originally Posted by J Tiers View Post
    Electroplated zinc is a short term coating for "sorta damp" areas.
    ASTM defines four "Service Categories" for zinc plating, which basically refer to the thickness of the zinc. The highest category is SC4, which they deem suitable for "very severe" conditions. SC4 requires at least 25 um thickness (about 0.001 inch).

    I've tested some hardware store fasteners, and they barely complied with SC1 ("very mild" conditions). Clear or colored chromate passivation improves durability, but it's still no wonder that zinc electroplating is often not well regarded.

    There is no doubt that hot dipped galvanizing is better yet, since the coating is quite a bit thicker.

    Ed
    For just a little more, you can do it yourself!

  10. #20
    Join Date
    Jan 2004
    Location
    Missouri
    Posts
    31,348

    Default

    yah.... 0.001" is not much, but may be more than many electroplated things have.

    Hot dip is maybe 5 thou or more, up to 15 thou in spots.. Zinc has a bit of "throw" to its protective characteristics.... so a hole in the coating is not always terrible.... but it is worse for spray or intermittent immersion than for direct immersion of large areas.
    1601

    Keep eye on ball.
    Hashim Khan

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •