rust removal

[Jerry V Lape]

Bought an old Craftsman fixed blade knife at a garage sale for $3.00.  It is typical knife which I recall was popular in the whitetail forests in the 1930 -1940.  Handle was stacked leather with black, yellow and red bands at each end, aluminum butt and guard.  The leather was totally withered, and I think it lived in a toolbox in the Arizona heat all this time.  Blade does not appear to have ever been sharpened and the steel has a black patina with virtually no rust.  I plan on replacing the handle with a couple antler scales and would like to bring the blade back to a high polish.  The question is there a way to remove the patina short of polishing it off.  The steel is unmarred, and the high carbon steel will make an excellent hunting knife again.   

[Hungry Horse]

 I’d start with Evaporust and see how much it will remove. That is about the safest rust remove I’m aware of.

Hungry Horse

[Gemmer]

Another vote for EvapoRust.

[Jerry V Lape]

 I am sure the Evaporust would be great. Ican only find it in gallon size jugs at about $31.  There for I accomplished the task with find #M abrasive film which I have on hand.  Thanks for the information about Evaporust.   

[T*O*F]

Ican only find it in gallon size jugs at about $31.

Be aware that it is NOT a one time use product.  It can be used until the ingredients are depleted.  I keep it in 2 different jugs, the factory jug and one that I pour the used stuff into.    Then if I have a particularly nasty job, I use the used stuff first.

[Pukka Bundook]

Never used evaporust, but if you want to keep any surface finish on anything, a bath in caustic soda works best to my knowledge.
Another name for it is lye.
Place part in a plastic container, pour boiling water over it, and add a tablespoon of caustic.

Out of doors and wear rubber gloves. Don't sniff the fumes.
Tablespoon should do for a gallonofwater at any rate.

It will act real ugly and boil.
If surface was real rusty it might have to sit a few days.
It won't rust in that solution if it sat for weeks.

Then empty solution down the drain. V good drain cleaner.
Wear rubber gloves as caustic eats organic matter and that includes your hands.
Flush parts in fresh water and scrub with soft wire brush or wire wool.
Any blued parts will still be blued.
Oil immediately, as caustic removes all oil and grease.
It works by dissolving the oils that bind rust to the metal.

All best,
Rich.







It doesn't remove pits though! 

[coopersdad]

Another good rust removal method is electrolysis.  It won't hurt the metal like using some chemicals (like citric acid, which works great but will eat your parts if left too long DAMHIK ) and works well, especially if the item is large and you don't have (or want to buy) enough evaporust.  I'm sure it will remove bluing, since it's just rust, and it will remove loose paint. 

There are a number of videos, etc out there, but all you need is a non-metallic container, a battery charger (non-automatic is best, ie with a "manual" setting), some washing soda, wire and pieces of rebar or some other sacrificial pieces of iron or steel.  These should be rust and grease free for a good connection.   

Put enough water in the container to completely cover the parts.  Mix a handful of washing soda in it. The soda just helps the electrons flow through the water better.   

Place the rebar or other pieces in the tank, not touching each other or the part.  Wire the rebar together with electric wire.  Attach the POSITIVE clamp of the battery charger to those. 

Hook the NEGATIVE clamp of the battery charger to the part.  I usually put a steel bar across the top of the tank, with a wire attached to the part.  If there are multiple parts, attach a wire to each one individually. 

Turn on the battery charger and you'll quickly see bubbles flowing from the parts to the sacrificial iron.  If they are flowing the other way, STOP and check the connections.  This is essentially an electroplating process and it'll likely mess up your part.   I understand the bubbles are explosive hydrogen gas.  I don't know if enough is produced to be a problem, so I always do this outdoors to avoid any Hindenberg incidents.  The rust is also flowing from the part to the sacrificial pieces. 

Pretty soon the tank gets nasty rusty foam on it.  How long it takes to be done depends on how rusty.  I usually leave it overnight.  Once the rust is removed, the reaction slows and stops.  The part will be clean of rust and the sacrificial pieces will have all kinds of nasty gunk on them.  The part may have some black stuff on it like evaporust does, but it easily washes off. 

I've never done this with any gun parts so far, just rusty tools.  This is a Stanley wood plane I cleaned up with this method.  I used Evaporust on the small parts and electrolysis on the main body.  I also just did a 5" Columbian bench vise that had been outside for years.  That would've taken a few gallons of Evaporust. 

[jim meili]

If you can find it try Zep acidic toilet bowl cleaner. Yellow jug. Cut it with equal parts water. Comes in gallon jug for about $10. I find it at the Menards store. Submerse parts for about half hour and they will clean up with some scotchbrite. Wear gloves or you will find all the little open spots on you hands.

[2 shots]

 if you have a harbor freight nearby they have qts. of evaporust less than $10.00 does work very well.

[Sudsy]

I collect vintage tools so dealing with rust is something I have a LOT of experience with.
I've used ever method possible from vinegar and salt, to citric acid, to all the various the off the shelf stuff, and over the years I've narrowed it down to two:

Electrolysis tank made from a 7 gallon bucket (same as Coopersdad) and for parts too small to hang in the bucket, Evaporust

[Top Jaw]

Gunsmith Mark Novak on YouTube uses a boiling water bath to neutralize rust (conserve) modern firearms he works on.