Corrosion Treatments - Recommendations Please

[Sloppysod]

Hi All, I have spent a fare bit of time under the car recently and have noticed a lot of Corrosion/Rust on various pipes, I intention is to clean, treat for Corrosion/Rust then repaint with hammerite or something similar.
Any suggestions on treating the corrosion/rust appart from a wire brush, I remember years (decades) ago using something called Killrust or was it curerust. Anyway, is there anything better out there these days?
Thanks in advance.

[mickthemaverick]

I still use Kurust now, I have two pots in the garage, still works for me as the same bit of Kurusted corrosion on the MX3 has remained solid and passed the last three MOT's without further attention!!

Own work

[bobins]

Kurust and similar products are tannic acid based and this is a well known rust converter, though it does have its drawbacks in that it'll only 'convert' a very thin layer of rust. This may be enough to stabilise the metal, but it's not a miracle product ! There are other products such as Vactan (note the 'tan' in the name - tannic acid !) which appear to be in a stronger suspension of PVA glue or similar - these can provide a more durable treatment.

[moizeau]

I've got some FerTAN. It's very thin, needs to be left for 24 hours, can be left unpainted for up to 6 months, can be recovered. It contains some nasties so don't drink it or chuck it down the sink. My brother has a barge and all the boatyards use it.

These are some bits that I wire wheeled back to base metal ready for painting. It can be used as a primer. It turns black, violet when done, needs rinsing in water afterwards and can be used even if the to be treated area is wet.

[bobins]

Evapo-Rust is a truly excellent product but is designed more for immersing items in it rather than painting it on. The downside is - it ain't cheap

https://www.evapo-rust.com/

[Michel]

I use XCP Rust blocker on my bikes. Gave it a proper clean and rust-blocking today. Now I don't have to clean it over the winter, it can stay filthy

[bobins]

+1 for XCP rust products.

[MattBLancs]

I thought Kurust and the like were based upon Phosphoric Acid? - I bought a couple of 5 litres bottles of that. Seems to work best if things are dipped into it, but can brush on. A bit thin. Mind your eyes if working overhead!

Note for dipping: don't use a tin can (e.g. bean tin, not aluminium can) and even better yet, don't leave the tin with the acid in it on a shelf for a few weeks.

I did and it ate through the bottom! Then made by a mess of the chipboard shelf too!

Came in HDPE containers so I've used margarine tubs since (or glass jars) and they survive.



On the mechanical rust remove side of things:
Flakey rust = "twist knot wire wheel" on the 4.5" /115mm grinder.
Thin rust of the surface = angle grinder flap disk.

Both the above much more effective than conventional wire brush and massively more so than drill powered wire brush.

Matt