acid to remove rust

[Qweaver]

I have several trailer hubs that have surface rust from years of setting in an open shed. I will need to remove that rust before I can put the races in.  I normally  use ospho ( phosphoric acid) to deal with light rust but I think it actually adds a coating to the metal and that may make driving  the races in impossible.  I'm thinking hydrochloric / muriatic acid.  I think farm supply stores carry muriatic.  Almost impossible to clean with sand paper.  New hubs, just old and rusty.

[thecfarm]

Ayup,my store has muriatic acid by the gallon.

[Barebuttminer]

Submerge the hubs in white vinegar for a few days and the rust will will be gone.

[Chop Shop]

Another vote for vinegar.   Not toxic either.

[starmac]

I have not done this, but have read that adding a cup of salt6 to a gallon of vinegar helps speed up the rust removal process.
I have also read to wash in baking soda and water when clean of the rust to remove the vinegar.

[Kbeitz]

I save old battery acid to clean out old rusty gas tanks and to clean up
old metal files that don't work anymore. Then I neutralize it with baking
soda and water. You would be surprised what it does to an old file.

[Al_Smith]

Citric acid also works .

[Qweaver]

I've got the muriatic  working.  We'll see in a little while.

[TKehl]

Just don't leave it too long or it could end up undersized or at least badly pitted.  Muriatic is diluted Hydrochloric.  Don't know if it has an inhibitor or not.   

[Al_Smith]

There's a guy in Australia on another forum of old Caterpillars I used to post on .He goes to the fruit market and gets partly spoiled citrus fruits and smashes them up in an old bathtub and sticks rusty old crawler parts within and lets them marinate for a week .
He has stuck entire frozen up tracks from small machines in a trough and says it completely unsticks them and never etches the base metal .

[Larry]

I occasionally use muratic acid to remove mill scale on hot rolled steel.  It works ok for that but it has a lot of drawbacks.  Getting harder to find the full strength stuff, its dangerous, and stuff flash rusts unless your careful. 

Three much better solutions for rust removal are Evaporust, sand blasting, and electrolysis.  I use all three depending on the project.  Either Evaporust or electrolysis would work on the hubs.  Electrolysis is always the cheapest but takes a little more time to sat up.

[Qweaver]

I used muratic and it worked well, but it does require a lot of care. About $6 for a gallon jug.   I'd like to learn more about electrolysis.  Where should I look?

[Crusarius]

The garage journal forum probably has 900 threads on electrolysis. Huge amount of info, what works, what doesn't. #1 thing is DO NOT USE STAINLESS ANYTHING!!!!! stainless puts off a toxic gas when used during electrolysis.

[thecfarm]

Look no more.
Larry posted way back when.
https://forestryforum.com/board/index.php/topic,6915.0.html

[Larry]

Thanks for finding that cfarm.  I remember posting that way back when someplace.

I only use washing soda anymore.  I also came across a Rubbermaid stock tank that works great.  When the water gets too scummy for me to stand I drain it out and start a new batch.

[thecfarm]

Larry,I got it bookmarked. ;)

[btulloh]

Not familiar with using washing soda to remove rust. Sounds interesting.