Summary for removing rust from steel axles Discussion
Removing rust from steel axles and bearing rails depends on how deep the corrosion is and how tight the tolerances are. For Brian Scott’s tractor-trailer axles, Christian Restifo said mild surface rust can usually be cleaned with #0000 steel wool or light sandpaper, then rinsed, dried, and protected with a rust preventative if storage will continue. He warned that scale is harder: it may need grinding, serious sanding, or a pickling/descaling bath using phosphoric, sulfuric, or citric acid, and that long parts or heavy scale may be best handled by a chemical supplier or job shop. Brian later noted the rust was severe on some parts, with scaling, and wanted to avoid removing too much metal. Goran Budija suggested a 5% ammonium citrate bath at pH 3.5, followed by a tannic-acid/phosphoric-acid rust converter and then wax or oil. In the bearing-rail question, the advice was more cautious: if the rail is a precision track for linear ball bearings, rust removal may damage the required surface finish.
Q. I work at a plant that makes steel tractor trailer axles and we have some excess stock that has been sitting in inventory for an extended period of time and has accumulated some rust. Is it possible to remove the rust without damaging the axles. I have heard that phosphoric acid or electrolytic rust removal using sodium carbonate
⇦ on
eBay or
Amazon]
are possibilities, but unfortunately, I know little about either. Does anyone have any information on this topic or any alternative suggestions. I greatly appreciate any and all comments.
Brian Scott
site manager – Marysville, Ohio
2007
A. How much rust in on the parts? And is it just rust or is it scale?
If it’s just some mild surface rust, you can easily clean that up with some #0000 steel wool
⇦ on
eBay or
Amazon [affil link] or light sandpaper. After removing the rust, rinse off the parts, dry them, and apply a light rust preventative (if allowed) if they’re going to stay in storage for a while. This should not affect the axles.
Scale may require grinding or serious sanding, depending on the amount. If you have some tight tolerances, this may affect the parts. It’s hard to say without knowing your specific application.
If you have a lot of parts and are looking to run them in a process washer or bath, you’ll want a pickling or descaling bath. These can be phosphoric or sulfuric acid. Some citric acid
⇦ on
or
Amazon [affil link] baths also exist. Keep in mind that removing scale can be very difficult in a chemical bath, particularly for HR steel.
If this is the case, you’d be best served by contacting a chemical supply company and asking them for a product recommendation. Or you can contact a job shop.
If you don’t have the equipment to run a bath and don’t have that many parts with that much rust, your best bet is to spend the labor and remove the rust by hand. If you have very long parts (say 10′ or more), finding a shop to run them in a chemical bath may be difficult.
Christian Restifo
– Pittsburgh, Pennsylvania
2007
Q. Most of the parts have a severe amount of rust on them plus some scaling, and some have mild surface rust. I was hoping there was some way to just remove the rust and see what we have left. I also don’t want to grind too much off the axles, because as you mentioned the tolerances are tight. I was told that phosphoric acid would even leave a thin layer on the axles to act as a rust preventative following treatment. We will, most likely, attempt all the possibilities. Thank you so much for the feedback.
Brian Scott [returning]
site manager – Marysville, Ohio – Marysville, Ohio
2007
A. Try 5% ammonium citrate/pH 3,5/, after rust removal paint it with 20 gm tannic acid
⇦ on
or
Amazon [affil link] /15 ml phosphoric acid/1 lit water solution /simple homebrew rust converter
⇦ on
eBay
or
Amazon [affil link]
, and you must wax or oil it! Hope it helps and good luck!
Goran Budija
– Cerovski vrh Croatia
2007
Removing rust from bearing rail
Q. I have a machine that saw salty air from ocean and the bearing rail rusted. What is the best method to remove it? It is standard bearing rail material.
Stamati Georgaris
– Ste-Julie, QC, Canada
June 24, 2020
A. Hello Stamati. I’m not sure what this “bearing rail” is, but I’m thinking it’s a shaft or rail-shaped section that linear ball bearings, or cam followers or possibly bronze bushings are guided by?
If it’s bronze bushings or some sort of cam followers that ride the track, I’d say go for it and try Goran’s suggestion of ammonium citrate at pH 3.5.
But if linear ball bearings run on this track (with the tiny balls directly riding on the rail), the track is probably a very hard, low alloy, highly polished surface and I doubt that rust removal will leave you with an acceptable surface finish for those tiny balls to run on. But please let us know, we’re all trying to learn every day.
Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com – Pine Beach, New Jersey
Need quick confidential answers? $25
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June 2020