Using Coca-Cola to fix rusty files

[agaboric]

I was wondering if anyone of you guys and gals ever heard of using coke to "fix" rusty files. Since I have some that were given to me I thought I would try it out, but I sprung for the cheap stuff and I do not think that it worked real well. So does anyone have any input on this, and how should you take care of files so they do not get all rusty, should I coat them with a little bit of oil or just leave them in a bucket of water like I have been doing (just kidding). Let me know what you guys think.
Thanks,
Andy

[omark]

actually, coke makes a pretty good penetrant. ive never used it on files, but i would give it a try. i know it is pretty rough stuff (and i keep drinking it).   mark

[Mark Elliott]

You need to actually use real, original Coca Cola.   That product has phosphoric acid in it.   That is what dissolves the rust.    It actually alters the molecular structure of steel.   

Mark E.

[agaboric]

You need to actually use real, original Coca Cola.   That product has phosphoric acid in it.   That is what dissolves the rust.    It actually alters the molecular structure of steel.   

Mark E.

When you say I changes the metal, does it change it in a bad way that I should not use coke? I do not want to damage these files but some of them may not be any good anyway so I guess it does not matter to much.

[heinz]

I think Mark meant to say it changes the molecular structure of the iron oxides, the rust.  It is fairly gentel on the steel itself altough it does have some minimal activity.  Phosphoric acid in much stronger form is an active ingredient in Parkerising, which may get you in some touble with traditionalists  Be sure to remove all of the coke residue.

I oil my files for metal working whem I am done.  The ones for wood use I jaust brush off.

[T.C.Albert]

I have never poured it on my files, but Coke will clean a battery terminal so an engine with a corroded one will start..
wicked stuff....
(and we regulate the sales of alcahol while the soda flows free...  )

[Mark Elliott]

I actually meant that the phosphoric acid affects the bonds between crystals.   I don't remember the mechanism.   It has been over 30 years since college chemistry and metallurgy, but I remember the warning about keeping Coca Cola away from stressed steel.    All engineering students at VA Tech were told the story of some researchers at Tech that were working with high pressure vessels.  The steel in these vessels was extremely stressed.   One a researchers spilled Coke on the vessel and left it over night.   In the morning, the lab had been destroyed.   The Coke had caused the pressure vessel to fail with explosive force.   The take away was to never have Coke or anything with phosphoric acid in it anywhere near steel under pressure such as in metalurgical test cylinders.   Perhaps someone else could enlighten us as to the mechanism.    

That said, there should be no danger to files as long as you clean them off after removing the rust.    By the way, Naval Jelly does the same thing as Coke given the same active ingredients.  

Mark E.

[Dennis Glazener]

I have used muriatic acid to clean rust off metal. I have also heard that some use it to clean/sharpen files but I have not tried that. You can buy muriatic acid at most hardware stores. Its commonly used to clean brick.
Dennis

[The other DWS]

Most of the commercial "rust away" rust stain removers found in the supermarket or hardware store home cleaning products areas have some form of phosphoric or "muratic" acid in them.

While they may remove rust they are dilute acids that present other hazards and must always be neutralized after use.

As to "sharpening" a tool it is only in the sense that they will remove rust that is clogging the teeth of old files and rasps.  Its not a magic potion.  If you have a rusty worn and battered file you may get rid of the rust but it'll still be a worn and battered file when you're done. 

[PIKELAKE]

I use muriatic acid all the time to clean files. It will not only remove rust but will remove all the crud a file card can not get out. I threw a file in the juice that I had loaded up with pewter from a knife bolster I poured. It cleaned the file just fine. I have never oiled them after but I guess you could. I wash them with soap and water. I think the acid etches them to a point where they seem to be sharper. Sometimes I leave them soak a few hours and sometime over night. I would not leave them sit forever though, just check em once in a while.

[John Archer]

Boggs Tool Sharpening in California use an acid process (they call it liquid honing) to sharpen files. They come well-recommended on some of the woodworking forums. Cheap too...which is always good.

John.

[KNeilson]

Not too long ago (beginning of the 20 Century) when files were hand cut,good files were expensive and hard to come by. Sharpening in acid (vitriol, or muriatic) was fairly common, as opposed to sending it to be reground and recut .You could squeak a bit more use out of dull or plugged file with this method. I have hand cut files and rasps and experimented with this technique, but have found that nothing will touch a new good quality file. IMHO keeping your files clean and protected, and sorted for use, will make them last much longer than abusing them , or buying used ones and attempting to sharpen them in this way......  Kerry

[agaboric]

When using muratic acid to redress the files do you need to dilute the solution or just put them in and be done? Also how long do you leave them in the acid? It sounds like I will give this a shot and like one said if the file is wore out and then pit it and move on. Thanks everyone for the good advice.
-Andy

[Dphariss]

I may have posted this before but here goes anyway.
While working at Shiloh Wolf bought a acid file sharpening system.
Yes it will sharpen files. BUT it also puts a "tooth" on the surface and material be it wood or metal bonds to this with wonderful tenacity. So one spends about as much time trying to clean the file as using it.
So when a file wears out, be a it a $5 mill file or a 50 dollar item it goes to the scrap file pile.
Though I admit I tend to hang onto the Pattern Makers rasps even when pretty dull.

Dan

[heinz]

Dan, the only thing I would question is the "scrap file pile"  I always think of it as the new knife and tool stock pile 

[rich pierce]

I use dilute nitric to clean files.  It does etch tyhem as dan said, but it will give a file fome new life till your replacement comes in.

Dan, if you have any Grobet pillar files in the scrap heap, they are worth about $10 a pound to me.  Make the best tools.

[Dphariss]

Dan, the only thing I would question is the "scrap file pile"  I always think of it as the new knife and tool stock pile 

I don't actually throw files out for obvious reasons.
But for most tools I have found its usually less time consuming to start with a piece of annealed O-1. It makes superior chisels and scrapers. As a result I use fewer files for tools now.

Dan

[heinz]

I agree on the 01.  I like the old file stock for scrapers, strikers and frizzen soles.  I haver never liked it for knives.  I also suspect some of the newer files have strange parentage and  I do scrap them.

[Dr. Tim-Boone]

Dan, the only thing I would question is the "scrap file pile"  I always think of it as the new knife and tool stock pile 

I don't actually throw files out for obvious reasons.
But for most tools I have found its usually less time consuming to start with a piece of annealed O-1. It makes superior chisels and scrapers. As a result I use fewer files for tools now.

Dan

Dan, Where can one buy O-1 steel online??

[John A. Stein]

Use white vinegar to clean and sharpen files. Soak them overnight, they will be covered with a fine soot-like coating, wash them in running cold water while brushing with an old tooth brush, dry with a clean rag or paper towel. Give them a light coat of oil.  The vinegar is dilute (3 or 4 per cent) acetic acid. The fumes are harmless, and the action is slow so if you have let them soak longer than overnight no harm is done. Use the cheapest vinegar, no need to get some fancy name brand.  Muriatic acid is hydrochloric acid, using it calls for some precautions. The fumes are very dangerous to breathe, and the liquid will burn your skin. To top it off,  the fumes will cause all the iron or steel in your shop to rust. Nitric acid is even worse.  John

[Birddog6]

Where can one buy O-1 steel online??

You can get the O1 steel here.

www.texasknife.com/

[josephprivott]

or you can get it from Fastenal for pretty cheap

[oneshot]

I've heard that sulfuric acid is good for sharpening files. I don't know about concentration -- never tried it.
Oneshot

[Bruce]

     I concur with Mr. Stein.  I soak my files in white vinegar till it turns black.  After removing the files I let them dry and the coat them with chalk.  Simple and inexpensive.

                                                             H. Calsore Cozgrave, a good friend of Notary Zojack.

[jim meili]

A toilet bowl cleaner that goes by the name of "The Works" has hydrochloric acid in it. About a 15% solution, I believe. Dilute it again with water, about 2 parts water to 1 part Works. It will take off rust, browning and bluing like you wouldn't believe. This is the stuff in the gray bottle and can be had for a couple of bucks at the grocery store. Check the label.

I also use it to etch barrels before I put the first coat of browning on. Wash the barrel down with this acid solution and let it set for a time then rinse completely and wash barrel with a grease cutting soap and rinse and dry. The acid will just etch the barrel a tiny tiny bit and give the browning solution a good bite. Not a necessary step but it helps me.

I found a finer toothed cabinet makers rasp, #50 I believe, at a second hand store for a couple of bucks. It was pretty rusty and in bad shape but after soaking it in this stuff overnight and cleaning with soap and water I got it back in service. Good enough to shape horns with.

A must is to use rubber gloves when messing with this stuff. If you have cuts or abrasions on you it will burn like crazy and cause an infection type sympton in a big hurry.