Thread: Best way to remove rust fromm HSS

There is a guy on youtube call outsidescrewball who uses CLR to clean up rusty parts. I have not tried it but it might be worth a go.

Cheers

Piers

Search the forums for any of the following:
Electrolysis
Citric acid
Hydrochloric acid
Sodablasting
Sandblasting
Molasses
Vinegar

However, for tool steel (were you want to avoid hydrogen embrittlement), I'd spring out for this stuff:
Evapo-Rust Home Page

For gods sake don't use Hyydrochloric acid (also often called Muratic acid) - it keeps attaching the steel after all the rust if gone. Phosphoric is much safer - converts the iron oxide ot a water soluble compound, and leaves a fine grey iron phosphate coating on the steel which provides a level of corrosion resistance. Phosphoric is also the active ingredient in Coke when you clean with it.

Molasses and Evapo-rust are Chelating agents - Molasses takes 4-5 weeks to work, but is much cheaper than evapo-rust - both do no damage to the underlying steel.

Given that you're dealing with light surface rust and cutting edges, I'd be inclinded to work them with a soft brass wire brush and oil - pretty much every other technique will knock the sharp edges around.

Of course, using them in a nice soft lump of alloy should clean up the threaded part nicely too.

I'd go with Gammaboy,a spray of WD 40 and just use them.

Cant say we have used molassis on something precise like tooling, but I know it does a reasonable job of plain old MS thats just been lying around.

As previously been stated would go the WD. To help keep the rust off in the first place, we use Lanolin. Just be aware it can build up on something like a mill table, not really an ideal thing.

This is part of the running gear on a car I am restoring all done with molasses,and what it was like to start with.







Eddie

Nice job Eddie good to see the project moving ahead, we've been stalled by the heat around here, can't drift too far from the airconditioner

I cleaned up a large rusty HSS milling cutter by boiling it in vinegar. I was amazed how well it worked.

Has anyone heard NOT to put springs in molasses? The reason given was that chelating changes the temper/chrystalline structure somehow. I can't imagine how, but I'm no chemist by a long shot....

WD 40 or light oil and use them.

Of course non of this works if it is flight rust.

Evaporust is excellent - easy to use, waterbased solution, biodegradable over time, clean up with water, re-useable, done in an hour or so. Is a bit expensive, but is probably the best.

Ahhh, I love the sound of flight rust in the morning!

I would just like to add that the most time that the metal was in the molasses was seven days ,but on average 4-5 days and would take it out and give it a wire brush over rinse off and back in the drum, a 1part molasses to 9 parts water does the job, I also use electrolyses on several parts just water and washing soda and a battery charger at about 4-5 amps
has never taken more thane 3-4 days to remove oil paint and rust.

Eddie