• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Phosphoric acid question

  • Thread starter Thread starter GSJake
  • Start date Start date
G

GSJake

Guest
I filled my rusty tank with a 1 part phosphoric acid 2 parts water solution. Does anyone have an idea how long i need to leave the solution in there to get rid of all the rust?
 
Until all of the rust is gone.:-D

Actually, I have no idea. But I'm sure someone will come along and deliver a fact rather than a smartassed comment.
 
It really DOES depend on how much rust you have. Peek in periodically to check it out
 
How long depends on how strong the acid is and how much rust.

I used POR metal clean (phosphoric acid) in one of my tanks and it took several days - rotating the tank several times each day. The rust was eventually converted but it left a chalky residue on the metal. Dumped in a bag of aquarium rocks, along with some denatured alcohol followed by vigorous agitation, and the tank came out clean. I don’t trust the metal to stay rust free after all this monkey motion so I used Caswell tank sealer to lock it all down.

The key to doing this job is to come up with a positive way to seal off the tank while the solution is doing it’s job. I used a rubber stopper in the main tank opening and a plate with rubber gasket over the petcock holes.

Good luck.
 
I worked in a factory that made oil seals. One of the early stages was making steel stampings. The steel coils often had some rust on them. Steel can get quite warm when it is stamped, which increases the rate at which it rusts. Stamping oil covers the parts, but it only slows rust, it won't eliminate it. So we had to remove rust all the time. Roughly about a half ton of parts were put into a cylinder with perforated walls. This was put into a tub of hot caustic (sodium hydroxide, pretty concentrated) to remove the stamping oil. The caustic was washed off, and it was then put into phosphoric acid to remove rust, then into a solution that would leave a phosphate coating that both inhibited rust and left a surface that rubber adhesive and rubber would stick to. Finally, it went into a rubber adhesive.

If one trip through the bath didn't removed all of the rust, we'd run it through again and again. Once in a while something was too badly rusted, and we'd have to throw it out, but that was rare. So try it, and look at it, and try it again until you can't see any rust, then leave it about twice as long to get the stuff that you can't see.
 
Back
Top