Sharpening files with vinegar - Before and After

[Davefr]

I read about sharpening files with a vinegar soak and was very skeptical but tried it on a 16" Sandvik ******* file that would barely cut. I soaked the bottom 1/3 of the file in vinegar solution. I used 45% commercial grade vinegar cut about 50/50 with water. Prior to the soak I cleaned the file as best I could. Soak time was about 10 hours. Here's images of a soaked section of the file and an unsoaked portion. I tested it on a scrap piece of steel and the section of the file that went thru the soak cuts way better than the unsoaked portion. The file was almost unusable before but now it cuts. I wouldn't say it cuts like a brand new file but it's way better than it was and no longer ready to scrap.

 

[KnurledNut]

Thanks for following up from the previous thread. This has basically been the same results I have had. Just be aware that vinegar flash rusts bad, so need to neutralize it immediately.

 

[autobon7]

Thanks for following up from the previous thread. This has basically been the same results I have had. Just be aware that vinegar flash rusts bad, so need to neutralize it immediately.

What do you recommend to neutralize with?

 

[KnurledNut]

What do you recommend to neutralize with?

I have used vinegar for all kinds of things, not just files. Where possible, I will wash with a strong mix of dish soap which also aids in getting all the remaining rust flakes and nasty black residue off. Also helps safely wash that junk off your hands. Some dishwasher liquid has a higher alkalinity if needed, but I wont use it with bare hands.
If its a smooth object, hand dry, air dry, sun dry. If something textured like a file, I have tossed them in the oven to quickly dry.
Then follow with oil or grease where applicable. For something I'm using immediately, sometimes just WD-40.
There may be better more scientific methods, but this has worked for me.

 

[slowtwitch73]

Think I'd call that teeth cleaning rather than sharpening... but looks effective regardless.

 

[M635_Guy]

That's pretty cool - will try it!

 

[Davefr]

Think I'd call that teeth cleaning rather than sharpening... but looks effective regardless.

I agree, they call it "sharpening" but it seems more like aggressive cleaning. I don't exactly understand the chemical process between the metal and the vinegar other then some etching?

 

[nadogail]

The mild Acid in the Vinegar removes the surface film from the teeth of the file, but it cannot restore it to like new condition

 

[amgent57]

A file card with solvent or mineral spirits is also good.

 

[four.cycle]

NOW you tell me.
I put about 30 old beat-up files in a Craigslist "FREE" ad and they were gone in 30 minutes. Advertised it as "knife maker's special!".

 

[tncatadjuster]

Back in 1975 when I went to university there was a myth that if you placed your shaving razor underneath a pyramid it would become sharp again, you just had to give it a few weeks to do it's magic. A friend in the physics lab did image tests and found the the blade would roll over and loose the edge after a few shaves. The pyramid did nothing but time would corrode the rolled edge and you would again have a somewhat sharp edge for a few shaves.
I can see where an etch would have the same effect on the file.

 

[Steve_P]

If you soak something in acid, rinse when removed. Then submerge in a water filled container. Then rinse. Then neutralize in a hot water and baking soda mix. Make sure to turn the item multiple times.

 

[amgent57]

I used 45% commercial grade vinegar cut about 50/50 with water.

No water on any steel, cast iron, etc

 

[Zewnten]

That's why he said it will surface rust fast after taking it out of the solution and to clean it off.

 

[Davefr]

That's why he said it will surface rust fast after taking it out of the solution and to clean it off.

Thanks, I scrubbed the file with a toothbrush and a baking soda solution to neutralize the acid then gave it a light protective spray of oil.

 

[amgent57]

Why stop at files?

Let your lawn mower blade soak in vinegar,
It'll be nice and sharp,

No need for those pesky grinders.

 

[Zewnten]

Why stop at files?

Let your lawn mower blade soak in vinegar,
It'll be nice and sharp,

No need for those pesky grinders.

Other than proving the old saying about keeping quiet so people don't think you're a window licker I'm not sure what you're accomplishing.

 

[ecotec]

Other than proving the old saying about keeping quiet so people don't think you're a window licker I'm not sure what you're accomplishing.

Well, hell… now I’m laughing… and the dog is staring at me.

 

[Wamsutta]

Why 50/50 ? I use it straight. But then again I'm using grocery store vinegar. I never heard of commercial grade.

 

[Davefr]

Why 50/50 ? I use it straight. But then again I'm using grocery store vinegar. I never heard of commercial grade.

I had this on hand and thought 45% might be too strong and food grade too weak.

 

[Wamsutta]

I had this on hand and thought 45% might be too strong and food grade too weak.

Let me tell you, food grade WORKS. I was amazed at how sharp my files got, but then again, I left them soaking for 3 months.

 

[Meursault74]

Why 50/50 ? I use it straight. But then again I'm using grocery store vinegar. I never heard of commercial grade.

Step up to lab grade >99% and singe your nose hair when you open up the bottle. Don't ask how I know.

 

[pcrov]

No water on any steel, cast iron, etc

Absolute nonsense. Water is what I use to remove rust. It's the largest ingredient in faux-vaporust. Alternatively, when I take a wire wheel/cup to something a spray of water on it first gives much more aggressive removal.

The rust and water makes a slurry that acts like an angry version of jeweler's rouge. It is a night and day difference. Oil works too, but it's a hell of a mess to clean up. Which would be done, by the way, with detergent and you guessed it - water.

You know the secret to safely using water on steel and iron?

Spoiler

Wipe it off.

Step up to lab grade >99% and singe your nose hair when you open up the bottle. Don't ask how I know.

Been there. Tried it with some focaccia, a little olive oil... just made everything taste like blood.

 

[seber]

When I do gun bluing, I use distilled water to boil the steel and protect the surface. Water can accelerate corrosion, but not always.
Now that I think about it, the next time I have to deal with rust, I think I will try boiling first instead of just removing.