After Evapo-Rust ? Tumbling???

[Joe Piro]

I am new here and I noted in "Introduce Myself" that reading your posts has given me a new respect for humble tools. So I have a lot of rusty tools that were in a fire and I was going to just recycle the metal., but I have been persuaded to save them.
I am convinced that the fire department puts a flame suppressant or other corrosive additive in their water. Tools that were not burned but only got wet rusted rapidly and severely. (Any fire firefighters know anything about this???)
I already put a batch through Evapo-Rust (that I learned about here). I was skeptical but now I am a believer. It did a great job and the chrome tools came out beautifully. (Some old USA Craftsman and some Armstrong, Indestro, Herbrand, etc.) Then I oiled everything, but oil is a mess for longer term storage.
However on to my question. I left everything in the solution for about 24 hours (got delayed in returning to the garage). I scrubbed each thing with a 3M blue pad (and a 3M green pad if needed) as I rinsed but they seemed to have a stubborn black coating on, for example, some cold chisels. Could I have left them in too long?
Does anyone have experience cleaning with a vibratory tumbler. For example HB has a five pound Central Mach. for $65 and an 18 pound Chicago Electric for $165.
Choice of media could be not too abrasive and then a Phosphoric Acid etch to finish and then a light oil would do. Any other suggestions?
It's probably not worth the cost of the Evapo-Rust for tools that can be replaced so cheaply such as cold chisels or punches, but I hate to waste stuff. I just saw Evapo-Rust on Amazon Prime for $15 per gallon. May need more for saws, screw driers, pliers, etc.

 

[Machinitect]

Joe, I have never had any luck with small tabletop vibratory tumblers. Any chance you have access to a cement mixer? I’d toss some water, sand, and maybe some rocks, nuts/bolts, into a cement mixer with your rusty tool assortment. Turn it on and walk away. They will be polished when you pull them out.

 

[Ralf11]

stubborn black coating is the intended result

rust is oxidized iron

in chemistry, oxidation reactions have an opposite reaction, a reduction reaction and that is what produced the black coating

plus, IIRC there is some sort of organic chemical in there too

on most of the rust removers sold they will tell you that the the black coating is like a primer and you can top coat over it (I usually put a good primer on top of it, then topcoat)

now, on a chisel you likely don't want to paint it; so, you'll have to rip it off on a belt sander

of course, the newly exposed raw metal will then rust, so...

 

[Joe Piro]

Machinitect: Actually I have a small motorized cement mixer from HF. It paid for itself on one project. The Evapo-Rust did a lot of good on lots of things, but I still have some candidates for the cement mixer.... great idea !
Thank you,
Richard

 

[Machinitect]

Joe, that’s great. You could also fill a bucket with your water, dawn dishwashing liquid, some comet, maybe some simple green, some rocks, nuts, bolts, sand as your media and put a lid on the bucket. Stuff a moving blanket around the inside perimeter of the cement mixer, with the bucket in the middle. That setup won’t be as aggressive. Good luck!

 

[d42jeep]

Evaporust does amazing things. This Plomb socket came out of it’s overnight bath with dark residue. Just use some fine steel wool and a hand wire brush to remove it. I use brake cleaner to finish it off and then coat it with Fluid Film to prevent future rust.
-Don

 

[Private Lugnutz]

The more carbon in the steel composition, the blacker it gets. As others have said, just scrub it off.

 

[humber2]

I am new here and I noted in "Introduce Myself" that reading your posts has given me a new respect for humble tools. So I have a lot of rusty tools that were in a fire and I was going to just recycle the metal., but I have been persuaded to save them.
I am convinced that the fire department puts a flame suppressant or other corrosive additive in their water. Tools that were not burned but only got wet rusted rapidly and severely.

In most fires plastics are burnt, these burn to Hydrogen Chloride gas among other nasties. HCl with water is acidic which creates the rust in bare metal.

HCl also strips the outer chromium plate layer and the base nickel plate is left stained when sockets in their plastic trays or on mats in cabinets get incinerated.

 

[JoCoSawdust]

I cringe a bit at the thought of tools+rocks+concrete mixer but I haven’t tried it so I won’t knock it. I’m an Evaporust fan and also get good results with Metal Rescue gel. Clean up and preservation afterwards are a must. +1 on Fluid Film.

 

[chenry318]

I typically remove tools from the evaporust, rinse under hot water and scrub with a toothbrush, then dry quickly and spray any internal threads or pivot points with oil to displace the water.

Then I have a very soft steel/brass wire wheel in my drill press to buff the tools to a nice shine which I then either paint, oil, or coat with BLO.

Below is an example of some pieces for a vulcan chain wrench I am cleaning up.

 

[Machinitect]

I cringe a bit at the thought of tools+rocks+concrete mixer but I haven’t tried it so I won’t knock it. I’m an Evaporust fan and also get good results with Metal Rescue gel. Clean up and preservation afterwards are a must. +1 on Fluid Film.

Let’s experiment a bit. I tossed some old hammers, rusted and grease caked gears, a brake drum, and a manifold in with some purple power, dawn, sand, gravel, and water. I will check back later this week.

 

[Machinitect]

Hammer after about an hour tumbling.

 

[theoldwizard1]

Vibratory tumblers are great for large quantities of small parts. I guess you can do a couple of sockets at a time. The size and type of stones used is key to the desired finish.

 

[Machinitect]

Hey Joe, I don’t want to hijack your thread with the cement mixer idea. I’ll move this experiment over to a new thread. I’m curious to see some of the other ideas about cleaning after evaporust.

 

[Joe Piro]

Machinitect,
I certainly don't consider it hi-jacked. I actually haven't used the mixer since i poured footings for a project 5 years ago. This will put it back to work. I am shooting for the best results and I will experiment with everything I learn here. Also I have a variety of sizes to do... some small some relatively chunky. Most likely I'll need a variety of methods before I'm done.
Eventually I'll get back with a report, although my personal projects seem to take a back seat to work.
Thank you to you and all the others for your input.