How to Sharpen Metal Files
HTML-код
- Опубликовано: 15 апр 2016
- Sharping file is fast and easy. Watch this video and learn how chemically sharpen your metal files.
Give it a try, it really dose sharpen the file. I promise you, you will be surprised. One side note the file must be dull not damaged to work. :-)
Popular mechanics article from 1992 with microscope before and after photos
books.google.com/books?id=seM...
Check out his link on Google books to learn how it works.
Workshop Receipts: For Manufacturers and Scientific Amateurs, Volume 2 page 235
books.google.com/books?id=ApF...
![Finesse2Tymes - Pretty Ricky [Official Music Video]](http://i.ytimg.com/vi/xIoP_mhYRT0/mqdefault.jpg)
![Cordae - Saturday Mornings (feat. Lil Wayne) [Official Music Video]](http://i.ytimg.com/vi/z2GYJua09F0/mqdefault.jpg)
Yup, my father taught me this trick in the early 70’s except he used full strength white vinegar. It took a few days but worked quite well. He also showed me how to forge a worn out file into flint steel to use for starting campfires. Miss him every day.
mine was the same....retired millwright...so many tricks...peace
if youre wasting hardened steel on a flint, youre a fucking moron. "forging"? son all you do is cut a piece off, you aint forging shit.
Sounds like an awesome guy!
So...how DO you forge a worn out file for flint?
I tried using sulfuric acid in my files and now I cannot recover all my data.
LOL
@@chrischiampo7647 Be like Hillary C.
@@papaike2 *killary
OhhNoo! All that Porn gone.. how will you survive?!
...Bruh
I was always taught that keeping files in a drawer where they could rub together was the worst possible thing you could do to it. I always keep my files separate.
There's a reason they're shipped wrapped in waxed paper... each file in its own pocket. Rubbing files on each other is how you get these nice bright curved lines on them.
you know he was making a joke, right. not trying to be rude or anything just really having trouble deciding if you could tell.
File steel is some of the hardest steel commonly available. By keeping files in contact with one another does not necessarily mean disastrous results ensue. File steel also has "toughness" which means that some abuse is normal. The way files are dulled is through pressure and extreme conditions such as exposure to water and other corrosive chemicals not through storage and random incidental contact with each other.
Yeah i was thinking, I've never heard this before. Like you i was taught the same thing. Don't rub them against each other and don't let them rub anything but what you are trying to file and only in the right direction.
@Steel and Tree Design the key to making a joke, is making it obvious. There is no indication of this being a joke. Most average people getting into working with their hands would take this video seriously and be mislead. Kind of a dick move kinda video if you ask me. Just makes this dude look like a fool.
I was given a bunch of old files and decided that I had nothing to lose by soaking them in acid. In my case I used muriatic acid and let each file soak for about ten minutes. I then neutralized the files in the baking soda solution. Some clearly cut better after the etching and some didn't. It depends on what you start off with. And yes, the acid cleans the files beautifully. So for all you trolls who have made negative comments, you have several options: 1) discard all your dull files and buy new ones; 2) Have your dull files hydro-honed where you'll pay to ship them plus the cost of the process; and 3) Try the technique described in this video. It all depends on what your expectations are.
They can send me all the files they like.
You've confirmed what I thought, it depends on what you start off with. A real worn file won't improve from this methode, but a file that is just dirty and/or corroded might. Nice tip, think I do step 3 first to decide which files to discard (and to reforge into something else). Think I'll just use vinigar and let it soak longer though.
I've just done this with all my files - everything from fine needle files right up to coarse rasps, and I'm blown away by how well it works. That's over 40 files I would otherwise have tossed - in NZ about $2k worth (as some were fairly specialized) One thing I would warn y'all of is being careful to neutralize afterwards, and then CLEAN the acidic patina out from between the teeth - otherwise they'll rust up real quick. As a jeweller I'm fortunate to own an ultrasonic bath, which was perfect for this job :)
And BTW yes - they were all clean beforehand - just blunt. In fact some came up sharper than new.
As a retired engineer with a small workshop my files are very important to me, rather than use a file card (which has steel pins) I use a brass bristled brush so it doesn't tend to blunt the file. When I was at school some fifty years ago, the metalwork teacher used this acid method to restore files. If you buy new files always keep one face unused for.use on brass, even files slightly worn files will not cut brass very well. I engrave the word 'Brass' on the uncut part of the file to remind me.
That's a good suggestion regarding the brass. A jeweler I know has separate files for gold, platinum, nickle and steel. Mixing flecks of metal between jobs would completely ruin the product.
I once made brass filings to mix with epoxy for a pottery repair. I spent hours filing a brass pipe fitting to make those filings. It never really occurred to me that brass would be harder to file but that project made that fact very real.
A file is much harder than a file card. You can not damage a file with it.
A file card will not blunten a file, the bristles do not engage with the file teeth, and are soft so even if they do (bent bristle etc) it don’t matter
I've heard that this was possible, but you gave us a great demo complete with safety warnings. It was a very good use of my time. I appreciate your good work.
Well said
Incredible! Wonderful and useful! I was always taught at school to NOT put files together where they could dull each other - but to chalk them (although nobody ever showed me what kind of chalk to use or how to use it!!) and wrap them separately in paper or cardboard. We were told as an alternative to stand them in a block of wood with appropriate holes drilled in it, and placed where no metal would bang against them.
David Chadwick explained that he used French Chalk on files to stop them from loading up. In England, French chalk is another name for what I call soapstone here in the states.
It works great. The soap stone is slightly slippery and stays in the teeth of the file. Chips don't stick to it.
That is exactly what I was taught and still practice that to this day! I do have a handful of dull files and will try the method demonstrated in the video. Worst case, I'll make knives out of them.
@@OldSneelock thanks! that's a good tip.
Wow, this is great! I have a bunch of old machinists files that were my Dad’s, that are all dull but I didn’t have the heart to throw away. This will rescue them, thanks so much!
For those who prefer chemistry a bit less harsh you can use undiluted vinegar instead of 10% sulfuric acid- it just takes longer.
nice! and much faster than they way i sharpen my files (one tooth at a time). esp liked the copper pipe cleaner. i use wood, but I'll have to try copper on the stubborn ones. thanks!
+This Old Tony
Im glade you like it :-)
This Old Tony One tooth at a time? You must have been a dentist in a previous life!
I was taught to use brass to clean.
This Old Tony was
Copper pipe is a great idea
I can even tell by the difference in sound pitches or notes the file produced before and after the process that you actually did a good job on that file, thanks for sharing this tip
Thanks for the comment. :-)
something I do as a blacksmith is I take regular chalk and rub it on the file. it will lubricant and keep the file from filling up and clogging.
machinists also do this when using a smooth file to draw file a work piece to help reduce/eliminate clogging and pinning which can damage the surface finish.
Same thing... except I rub some borax into the file. whatever chalky stuff you've got, I suppose.
+Eagle Bird Knives Never thought of Borax or Soapstone, I have thoes by the pallet loads, thanks I'm going to try them.
Yes, 'load' the file with chalk to prevent it clogging/blocking in the 1st place, totally agree.
Absolutely. If you are filing aluminum and other soft metal that are sure to clog the file, loading it up first with chalk is your best bet. Been doing it for decades.
i was skeptical that it was going to do much, my files are pretty old and used hard, i wasnt amazed , i was absolutely blown away, they are like new ,it worked wicked awesome, mind bottling !
I use a very similar method on my files, but use a 100% salinity table salt brine and DC current to electo etch a few microns off the outer surface. Microscopic inspection before and after shows a clean sharp edge where they had been rough and rounding.
You would be better to use washing soda as the electrolyte as it is less corrosive and not hygroscopic if you fail to rinse some of it off.
It also does not release chlorine during the reaction.
Thanks! After watching the video and realizing what this process was accomplishing, I immediately wondered if using current to blast away the surface would also work!
Although I appreciate this is 2yrs layer, I have some questions, if you happen to get this notification...
- What did you use for the other terminal, and how far away?
- What power source did you use? (and at what voltage, if it is a variable source?)
@@DUKE_of_RAMBLE I used the file for the anode (-) and an old bolt for the cathode (+). I was just using an old 120 volt ac to low amperage 12v dc transformer like you would use to power a cordless phone base. An adjustable power supply would be nice but I did plenty of electro etching and black oxide coating with that basic setup. ( for oxide coating just reverse the polarity to deposit iron from the sacrificial anode onto the part you're coating.)
@@justindunlap1235 Awesome! Thanks.
So if you don't mind, last 3 questions (hopefully lol)
*Duration of time left in there to etch?* Based on whatever length file you were sharpening, and I can try to extrapolate from there to fit my file lengths.
*Was it a long cathode (bolt) or completely random, and approx what distance from the file?* In my (limited) experience, the length of each node, and even their angles relative to each other, drastically effects the path the current takes (electricity liking _"path of least resistance"_ and all that). So a short cathode, even if dangled mid-way, would end up doing more work nearest to it - potentially leaving the file with low spots where more metal was liberated from it.
*Size of container needed (or that you used)?*
Thanks again! 🤘✌️
I would use a plastic container approximately 14x18x4 inches with a very long bolt, long enough to touch the bottom and still protrude from the solution. I noticed I would get the most consistent results when the cathode and anode were placed vertically at opposite ends of the tank, as for duration it's not more than a few (3-5) minutes to get a decent etch on a 12 inch file ,depending on the power supply used, I've tried using a 12v battery charger before and was amazed at how fast it would etch, for oxide coating the longer you leave it the thicker the coating will be.
0:56 Before I was allowed to be enrolled and studying at the High School in Aachen to become an Electrical Engineer, I had to absolve an internship, learning to weld, filing, sawing, etc.
The studies did not work out but what I learnt in the training workshop proved priceless throughout the next 55 years and still do.
Dale,
Thanks for this helpful trick! This afternoon, I've been working on restoring about 8-10 files that I thought were total junk... just tried the first 3 that I took out of the acid bath, and they cut like a new file!
I used Muriatic Acid (hydrochloric acid) instead of sulfuric.
Probably the best tip in this video is to use a piece of copper pipe to make a file scraper... it works better than any file card ever created for cleaning the file... and is probably responsible for 75% of the success of this method.
Thanks again, I've now got about 10 more "new" files for the shop that were destined for the scrap bucket!
Thanks for your comment, I'm so happy you saved those files. :-)
Works like a champ!
I have to say we all should be listening to the old timers more we would all have more knowledge . Those old guys and gals have made my jobs a little bit easier , thanks dude.
Exactly..the right way wasn't always the easy way..but in the end you have a quality product..with quality work
I've been hand filing saw teeth for 35 years or so and I've gone through many files. As such I've been using this method to save a few bucks. It really works.
unclogging or sharpening this is something lots of people did not know how to do and will help them with there files working again and its very easy...nice job.
In an old book I have re sharpening files it says: Immerse file in acid for a short time. Then pass lightly a piece of cork along it to remove acid from the top of the teeth. Immerse again. Pass the cork and repeat as necessary. What is being done is actually to not let the acid eat away the top of the teeth but only the valleys. Never tried it meself.
this would work.... but u would need to go at it a while
That sounds like sound advice.
That is not very rational thinking. First the valleys are not dull the teeth are. Second the second you dip the file into the acid it is back working on the teeth.
@@thinkfirst6431 Actualy, it is very rational. You are just not getting it. Luckily science does not give a rip and it just keeps on doing what it does even though some of us are just a little to invested in cognitive dissonance to understand it. If you really refuse to accept proven concepts then just send all your dull tools over my way. I get a kick out of bringing old tools back to life. Save a grip of cheddar in the process.
@@edstimator1 Actually it is not very rational. no one ever cut anything with the valley of a file unless it was ground down into a knife. The acid is doing the work the cork might at best be wiping some of the sludge off of the top of the teeth speeding up the process an amount not worth the effort. The cork is too soft to effect the metal and would absorb some of the acid so that your just rubbing the metal with a soft material soaked in acid.
The acid is what is doing the work. The acid eats the metal at a constant rate over all of the file. The reason that it works is that the tops of the teeth are worn at different rates. The very thin tops are dissolved at a "faster" rate than the thicker worn parts of the file so that when the worn parts of the teeth approach a sharp edge again the thinner parts and the thicker parts join in a "sharper edge in roughly the same time making the surface of the tooth more or less "sharp". No one gives a crap how deep the valley is, only how sharp the cutting edge of the file is.
The acid dip only works as long as the hardness of the file is uniform in depth. If the hardness varies so will the chemical sharping. Acid dip works, the cork is just BS.
This is a time honored method, and it does help to improve the files cutting ability. The acid etches the file steel. This method does have its limitations though. For example, files that have been abused, stored or used improperly. All of which are a very common issue.
I have seen many a file just tossed in a drawer or bin with other hardened steel tools and files. I have also seen files used with saw like, or in a scrubbing/sanding motion. This will rapidly round/roll the file teeth over. Even milder (softer) steels can have this effect on a file if it occurs often enough.
Or they attempt to file on steel that has been work hardened, think, an edged tool (such as an axe) that has been used to strike something hard such as stone. This high speed impact crushes the edge of the tool, which causes the molecules at the site of the impact to become heated and compressed.
After the impact the molecules at the site of the impact rapidly cool and often become harder than the file being used to resharpen the edged tool. This sharpening attempt literally rounds or rolls the fine edges of the file over, thus, destroying the cutting edge of the file. Files can only cut materials softer than the file itself. If the steel is too hard for the file, the steel must be carefully ground to remove the work hardened steel.
Any action that causes a file's steel to become hot will soften the steel of a file, making the file useless as a file.
To me all of these forms of file abuse are indications of clueless and unskilled workers (aka: greenhorns). Or... people that just don't give a damn.
Every winner was once a beginner…
You weren’t born with natural knowledge of metallurgical science and file maintenance. Greenhorns can learn
wow I've been machining for 19 years and this is the first time I've heard of this. awesome
Thanks
Retired machinist here. This actually does work on your files and it will also work on endmills made of High Speed Steel.
Great video!
For those of you that have one, and are still into analog, this is also covered in The Machinist Handbook
Ive been a tool maker for 30 years and clean my files with a wire brush. I buy new files sometimes, they are a pleasure to use.
I do the same but my brush is on a bench grinder..lol
I learned the same trick as an apprentice, the only difference was that it was a 9% sulphuric acid mix and it was left in the solution for 2 hours. Afterwards, you put the file in cold water and agitated for a bit. It worked well. I never did it a second time but I remember being told it only worked the once. Good post, thanks.
Hi The run Reaper, Thanks for your comment. I like stories like that.:-)
An old machinist taught me many years ago about using a soft piece of metal to clean a file. I’ve still got a piece of brass shim shaped like an L that I use. I’ve used aluminum, it works fine. Had a piece of brass dar stock that I had used for a punch pin that had mushroomed the head, that mushroomed head worked well. Obviously, the copper you used here does the trick. I’ve never used chemicals to clean a file, but I’ve not ever had a rusty one. Well done and thanks for the video.
Maybe people should try it before making comments. It's amazing how smart we think we are. Ignorance is a curse.
I like the vid. Great job.
Thanks for sharing. As Michel Nadon said earlier, it would be nice to have visual proof of the effect of acid etching on the cutting edges of the file. In theory, what you are promoting might work if the acid etches all surfaces equally and a round tip will become a sharp tip as a consequence. However, I think we need to see this happening to be convinced, My feeling is that sharp edges will be strongly attacked by the acid and come out rounded.
I follow your logic and agreed with it, but it dosed sharpen the files. I don't know why all I know is it works. :-)
Hard to believe someone thinks file-to-file contact would *sharpen* rather than dull it.
Also, you have the sweetest vise I've ever seen.
Neat Dale :)My apprenticeship was as an Electrical Fitter (Fitter being the term used in UK rail industry for Craftsman) we did machining, welding, fabrication as well as electrical wiring, conduit, coil winding; at the end of I then worked on diesel locomotives and large fixed plant
+Rich ok
You did a lot that is very cool.
1: never heard of that one with the files self-sharpening in the drawer.
2: That drain cleaner is water, detergent and some acid... you need concentrated sulfuric acid to create that exothermic reaction and the concentrated sulfuric acid looks like yellowish/brown oil or thin honey.
3: removing rust and slightly etching the file to sharpen it with acid - pure genius! Onestly!
Thanks for sharing!
Thanks for your comment. I can't believe you have never done the file in the draw technique before. LOL
concentrated sulfuric acid is clear. no tint.
unless it is adulterated.
You have to read the labels. Some drain cleaner is pure concentrated sulfuric acid.
I always use citric acid, it works just as well but is less bad for the environment. Also, I use a 40volt dc power supply so as to speed up the process like in Electro polishing, the electricity makes more metal erode of the planes than of the points and the file becomes even sharper. After I use the citric acid I bring it to a recycling company, fresh citric acid you can pour down the drain, it will be deluded and become harmless. Citric acid that is used with metal can be full of chrome 6 and 7 so recycle it responsibly. The acid I use comes from citrisurf(brand name) ps. great video not many people know this trick and throw their files away
Thanks f0r your comment
This is electrochemical machining, and probably much superior. Does some iron plate out on the Cathode? Is the cathode lead or stainless or does it matter? I think this is the right path and hope you will publish something.
How do you connect the power supply? I tried something similar with a 12 volt battery charger and just fried it. Didn’t know who to ask but hopefully you can explain the correct method?
Electroetching will be faster *but* the tips of the file teeth have a higher electrical potential and will erode faster and as a result, the files won't be as sharp, it may even dull the file more, depending on the electrolyte, voltage and current. That what the process of electropolishing does, it removes the high points on a surface to produce the polish. There are shops that specialize in electro deburring.
Interesting! I may have to try that twist..
Thank god for you tube and passing this old timers trick onto the next generation! Keep up the good work!
A knife salesman taught me that 40 years ago,To test a file to see if it is sharp lay a dime on the file and press with your thumb,a sharp file will dig into the silver and it will not fall off.Leave te file in the acid over night and you have a smooth scrapper with no teeth.
Great video
+Walter Poley I wonder if that works on the 'new' Cu/Ni dimes? Or was this with a real Silver dime?
Real silver or silver coated
+Walter Poley
It hard to find a real silver dime now a days. :-) great comment
yes, I am a swordsmith, and I really go through files (filing spring-hard steel a lot). copper and wood both work. For small files, get a popsicle stick to clean them out. Same trick.
Am pattern welding files into knives with high nickel saw blades for contrast put into nitric to reveal. I imagine the nitric acid(dilute) would work nicely and quickly for file sharpening.
Can you show us a close up of the teeth before and after the cleaning? I'm intrigued what this actually does to the file.
It dissolves the surface which brings the teeth back to a sharper point, if you try it yourself you’ll see what I mean, if the teeth were rounded before, the two intersecting planes of the tooth dissolve evenly bringing the two planes closer together and therefore deleting the rounded tips of the teeth, I agree, if he has the close-up cameras ability to show it, it would be helpful to explain using the visual aid to show this effect. Even a drawing would be helpful
@@b2manufacturing Thanks for the explanation. It seemed sort of improbable but now you explain it the process makes sense.
I think it’s actually cleaning the file I think the acid loosens debris from the tooth relief .
@@b2manufacturing the rounded cutting edge will as fast resolve as the surfaces. I don't think it will make it sharper, but the proces will clean it more up, so the teeth will become more corse regarding the high and lows of the teeth, so it feels like it's sharper again.
Better buy a new file, they are not that expensive.
We were taught to use blackboard chalk when filing , this stops the teeth from becoming clogged with metal filings . Regular brushing & reapplication of chalk to the teeth while in use & storing of files protected in cloth help make a file stay sharp for a very long time
I have a drawer full of old files that are VERY dull but being a pack rat I didn't have the heart to scrap them. ( always thinking I could do something with them)...
Now I have a mission. when I get a chance I will try your idea out.
thanks for your video and knowledge It's amazing that if you get a chance to spend some time with your elders what they can teach you. They didn't get old sitting under a tree.
I am a retired auto tech and I have 4 sons. when ever we are working something and we are stuck on how to fix the problem most of the time I will come up with a plan on how to get around the problem. Its to the point now that they teach me things. When I do and it works I just tell them that I "Read it in a book once" The book is----" life experience. "
their book is growing also.
try this, take one random file and leave it soaking in white vinegar for a couple days. compare it to the experiment above. i'm curious to the results. :)
ive used vinegar to achieve the exact same results as this vid so Id appreciate a 3rd party opinion.. thanks Greg
You could always make them into knives.
Lol, I buy a lot of garage sale files to make tooling and knives out of, but after cleaning they work too well as files. If I make a knife or something out of one of them - seems like I always find a use for the file I just destroyed.
Great information and education, thank you. I now have 3 generations of files to clean up.
Is a generation still 20yrs ?
A similar process I tried does sharpen dull files. Whether the system used here sharpens them depends, I suppose, on how badly dulled they are. The copper cleaning tool is a great tip. I used muriatic acid from a masonry supply house and vessels made of PVC sewer pipe with an end cap cemented in place. I left the files in for many hours which ate away a lot of steel, too much in some cases. Worse, the fumes seemed to alter the chemistry of my shop. Here in a dry part of the country I'd never had rusted tools. Since the acid etch everything wants to rust so do it outdoors.
This a common problem with hydrochloride (HCl or muriatic) acid - even the fumes from an imperfectly tightened lid on the HCl bottle can cause corrosion through your shop - best to store strong acids in their own steel (sacrificial) cabinet with a bunch of seashells in it.
@@mikelastname Sounds like wise advice. Thanks.
Thanks for sharing the old timers instructions with us. I just love this sort of thing, because if you didn’t know anyone who knew how to do this…then you didn’t either.
I heard about this trick many years ago from an old time sharpener. He also used files for a living to sharpen very fine cutlery. He said they would be ok but not great. I guess i will have to try it for myself.
When you get new files, keep them separated and dry where they won't bump into anything. I have my own handmade rack I keep them in, much like a knife block. Card your files often and keep them chalked. Use the proper file for the job at hand. If you take good care of your files, you won't have to resort to dipping them in acid, which only works for a little while (the file will quickly dull again) with diminishing returns. For all this trouble, you might as well just purchase a sharp new file and take good care of it rather than handling caustic chemicals.
At last!! someone with some common sense.
Start at 1:40 if you wanna skip opening comments.
Thanks
I did it and works really fine! Thank you very much! You save my old files.
Thank you…looking forward to trying it. The most important takeaway was the gentleman sharing lots of knowledge with you!!
Good video, I've never heard of using acid. I keep my files clean and not banging around but this will keep them more usable longer, then I'll make knives or tool bits out of them, great steel.
I have been doing this for many, many years, but I now use a piece of 2" pvc drainage pipe, capped at one end, so I can fill it to cover the whole of the cutting parts of the files!
Great Idea, I'm going to have to start doing that.
@@BuildSomthingCool Can you also teach me how to sharpen each file tooth too please. My 5th and 7th tooth are blunt and it's making a funny sound, kinda like it's out of tune.
Excellent advice and a real money saver. I like your file cleaner made from a copper pipe cleaner. One of my old file cards has a 2" long copper pick that stores in a slot along the top of the file card. Helps remove the embedded pins from the files but slower working than your copper pipe. I always check my files for pinning before doing draw filing to prevent ruining my work. Thanks for the file restoration tip.
+Paul Jones
thanks for your comments
How timely. I was only this morning thinking about sharpening files. I had heard of this years ago and wanted to look up how to do it. And here's your video showing me exactly what I needed to know. Thanks a lot.
Mart.
+martsrods
IM glade I could help
Great tip! Old files can be recycled into scrapers, knives, lathe bits & makeshift vise jaws too! Thanks!
The steel in old files is also a favorite of custom knife makers
Nice comment :-)
Do NOT use them as lathe bits ---very dangerous
@@davidwrighton3914 You are right. Files are too hard and brittle for lathe bits. But they might work if you tempered them to make them just a little tougher and less brittle.
Old files can make great knives that how I sharpen mine.
@@jerryking1434 fukkin idiot ... You turn it into a knife. It's called recycling.
You cannot sharpen any file... unless you have equipment to cut such fine, angled, and uniform angles...
Or have you mastered Nicholson ??
Kenneth Kustren your either super slow on the uptake and can't process humor, or you're just a super big asshole that wants to spread his asshole comments around and put people down. William Miller was making a fucking joke, and yeah wasn't the funniest but it made me laugh. You need to get some help with that because it's going to end up destroying you one way or another.
William Miller I've made several knives from old files myself. Just remember to do both heat treatments so they aren't so brittle then to put temper back into the file.
But how do you use the knife as a file after you turn a file into a knife.
@@kennethkustren9381 your mother
That was awesome!!! I have so many of them that won’t work anymore and always wondered if we even possible to re sharpen files but you came to the rescue!!!! Thank you! ❤❤❤❤
This is how I've sharpened files for 45 years but I didn't know about the copper pipe. Thanks!
Glad I could help
People arguing whether or not this actually sharpens vs. cleaning, have forgotten all about how we used to "acid dip" our muscle car bodies to make them lighter. Acid evenly removes metal from all exposed surfaces. That includes points, ridges and valleys. Let's picture ridges and valleys of a file. If the file is dull, the ridge will be a mini plateau. If you acid etch, the sides of the ridges will eventually wear away until the plateau becomes a thin ridge again. Thus, making a new point or ridge. Likewise, the valleys get deeper.
If you leave it in solution too long, you'll end up with flat bar. And if the file isn't extremely clean and wire brushed, all the etching action is happening on the left over crud, and not much on the actual file.
Thanks for your comment. :-)
My last year and a half in the US Air Force I worked at the largest rocket sled track in the free world. This is at Holloman Air Force Base in New Mexico. The time I was there we tested components for the F-16, the Space Shuttle orbiter and the B one Bomber. The unit number for the squadron has changed in the last few years, but there are several videos on YOU TUBE under high speed rocket sled track. It was the most interesting job I ever had.
thanks for you sharing your story
My Dad who was a sheet metal man for over 50 years used to tell me you can sharpen a file with acid but I never knew it was that easy. Going to break out the stack of dull files I have and get busy now.
Good luck with that, this video is a joke.
Theoretically speaking, using your files correctly should keep them sharp... this is a great instructional on how to clean them up, which is also necessary!
thank s
You forgot to mention that before the acid wash you must clean and completely degrease the file before dipping it in acid!
Acid will not touch metal that is oily or greasy.
good point
Actually acid dissolves oil and grease too
Mostly it does not, oil needs to be removed with a caustic solution or soap, acid will mix with water but as it is mixed with water it will not mix with oil.
@@Mentorcase For the price of cleaning a file before etching it, I'll clean it first with TSP. Thanks
Do this outside. The fumes from the acid are HIGHLY CORROSIVE do not do this process inside. The fumes from the acid will settle on anything metal and corrode the surface and you will have rusty tools or machinery. I do decorative acid etching and found this out the hard way when i did some etching under a cabinet that held all of my taps and drill bits. It corrodes the protective coating and made everything rust.
In a similar way I found that bleach vapors will rust any steel that they touch. My binoculars were stored in a cabinet. The laundry soap was moved to a lower shelf in that same cabinet so it would be easier to reach. When I found my binoculars that fall it took quite a bit to clean off the surface rust. Good thing my guns weren't in the same cabinet.
Do this outside! Or in your toilet!.......... >.>
You must be a bachelor. 😈😈😈😈
.... It's drain cleaner for crying out loud. Nice haircut though.
Big Dan No slam intended Big Dan. I just know if I ever used the toilet for sharpening files I would have to have a food taster for the rest of my life.
Despite that it has it's merits. Fresh water anytime you need it. Self rinsing. Porcelain bowl that isn't bothered by acid. If it wasn't for winter hitting Michigan 6 months out of the year I'd be seriously thinking of installing one in the shop for just such uses. :-)
I bought a Nicholson file a few months ago, that thing was used SO often, it’s getting dull, I think I’ll try this. Thanks!
My gramps taught me to do this years ago only using white vinegar. If you use household which is 5%, the files need to soak for up to a week, depending on how bad they are. Although this does take substantially longer, it is much safer and less expensive than using sulfuric acid. You can also use industrial vinegar or acetic acid but it is much more expensive and a lot stronger at 30% and requires the same saftey precautions as sulfuric acid. I have also used muriatic acid and it works just fine. Just keep the dilution to 10 to 1 or ten to 1.5 water/acid and keep an eye on progress so as not to let it go too far and ruin the files. Keeping files all piled together is a sure way to dull tgem quickly. Store them separately in a rack or make covers for them to protect the teeth
the solubility of sodium bicarbonate is around 100 g/L at room temp. So if you have a water volume of ~4 L, like it looks like you do, you would need right around a pound of baking soda before it reaches its saturation point (Ksp). Just letting you know.
Btw, ego in their right mind would think that storing files I drawer, and letting them rub together, would sharpen them? That makes no sense whatsoever. It would do the opposite.
It does make them duller. Been around them for 40 years, using them for 30.
thanks
Andrew Delashaw pretty sure it was sarcasm.
Bah! If you'd rinse the stinking files off first, you'd only need a little bit, it doesn't have to be saturated! Just throw some in there.
A soft aluminium strip, run across the full in the same direction as the cut in the surface will form teeth and clean the old filings out allowing it to cut again . A blunt file is usually just a clogged up file . If it's dull , you cannot sharpen it
A strip of brass, pushed across the file at the same angle of the teeth will work even better.
Doesn't the sulphuric acid dissolve the metal making it thinner at the teeth sharpening it in a way?
or a stiff brush, everyone has that laying in their shop anyway.
Yup - it's known as 'chemical sharpening'. Even etching of the tooth surfaces leaves them with a sharp edge. Cleaning the file first is essential, however, as gunk in the teeth will protect the faces, meaning you'd only etch the tips, rounding off and blunting the file.
It will make them slightly sharper for a short time, it can only be done a few times and it will never be close to factory new
I remember this method being used by file cleaners on the streets in Old Delhi India. Thank you Dale..
I gotta try this, I have a few old files at home and at work that thankfully I just couldn't seem to throw away.
Thanks
Can I use this to clean my criminal file?
Bleach will work much better than acid. BleachBit in fact. The top criminals in this country used it successfully.
Da L. that's what Hillary uses?
Antifoul Awl
H
Antifoul Awl ACriminal file is nothing else than history.
Great series . Thank you .
+SOCOLVN
thanks
Metal Tips and Tricks .
Best file sharpening video I found so far and I've watched a lot of them
Using that file without a fitted handle is file safety No.1, you should know that a file tang in the wrist hurts my friend.
Old golf balls make great file handles.
I found having my old rusty files hard grit blasted cleaned them perfect and restored cutting performance. Experimented with grits and found silicon carbide grit in medium(80) did best job.
If the gullets are deeply packed with rust then yes grit will remove that but it will also Nick any sharp edge tooth that you've already have. Especially large coarse Grit . Anyone trying ball shot or well used Steel split shot will just peen over the sharp edge. 80 grit will make a really jagged Cutting Edge serrated should try something a lot finer or even use baking soda as the blast medium which is softer than the steel and won't dull the sharp edge but will remove the rust and oil , crud , Etc.
Mechanical engineer.
my father taught me to use muriatic acid for sharpening files. baking soda is a great neutralizer.
thanks of ryour comment
I use that in my garage to get rid of mill scale. I came out the next day to everything rusted. If only I did research first!
I had no idea a file can be sharpened, only cleaned (using my file card).
Thanks! ;)
So fortunate to run into a person with knowledge and stories from the 50s. TU on vid.
I have done this using plain cheap white vinegar. Leave the file in the vinegar 10 or 12 hours then rinse well and oil it or use some WD40. I know all of the anti- WD40 stuff but it works for me so save your keyboaed
my keyboard is already blunt... WD40!! pff!
Thanks for your commnet
Great video Dale! Could you show close up shots of the metal piece being filed before and after? It would be great to see the difference.
Great comment. next time :-)
Yeah what a shady ending geez!
I heard about sharpening files over 50 years ago but forgot what type of acid to use, thanks for the refresher. Too bad that I am now too old to need the information.
I have successfully done this but not in such a clean and safe manner as you demonstrated. Thanks for showing me the right way.
LOL
Thanks for finding the Popular Mechanics article. That answers the "I won't believe it without photomicrographs crowd." I wonder what their next objection will be?
LOL
funny thats the only article that says this is sharpening that ive seen
Thanks for your comment. I wouldn't have looked in the description otherwise. Why doesn't this work for knives, chisels, or drills though?
Hey guys, if you don't like the idea of acid sharpening don't use it.
It does not matter to me whether you need to find reasons to contradict the idea or not, but some of your comments are really a bit thoughtless.
Technically you probably could use acid to sharpen knives etc, but you would not use it. The knife is a thin tool and eroding away some of its thickness is unhelpful. Chisels do not suffer from a lack of thickness, but eroding metal would alter its dimensions, also the erosive process is not very uniform, so getting a nice even sharpen will not happen. Drills also do not want to have their dimensions altered. Also with the drill bit the angle of the cutting area is quite large, unlike the angle of the cutting part of a file. The result would be minimal sharpening for significant loss of metal and loss of dimensional accuracy of the tool.
Surely, the proof of the pudding is in the eating. Just try it.
The idea of sharpening drill bits as a test of the process has been brought up before. The differing actions of a file and a drill bit are the reason it isn't used to sharpen drill bits.
Drills use the width of the point to define the diameter of the hole that is drilled.
Acid removes metal from every surface it comes in contact with. The drill bit will become smaller in diameter just as fast as it becomes sharp. You end up with a drill bit that is sharper but with a random sized diameter
The same, two surfaces being eaten away, process exists because the diameter is the measure of the distance between the two sides of the bit.
It will work on a knife but who wants a thinner shorter knife?
Besides each of the other suggested arguments against using acid, points out a device that is normally sharpened in a different way, as an example of the acid process being a failure. If it were as easy to run a stone down the edge of the files teeth as it is a knife we all wouldn't bother with the mess of acid sharpening.
Milling cutters are ground on center grinders because they have fewer flutes than a file would have in the same distance.
The operation of the file doesn't depend on it's width or thickness as long as it is sharp and strong enough to not break during use. 😊
If you would like a good history of files, how they are made, and used I recommend The File It’s History Making And Uses by Henry Disston & Son. Upload of a copy from the Stanford University Library is available here.
play.google.com/books/reader?id=1mNBAQAAIAAJ&printsec=frontcover&output=reader&hl=en&pg=GBS.PA7
who said rubbing file against file at the incorrect angle will sharpen them? iv never heard that
Miles11we
I think he was joking
Laurence Rilling I doubt it, I have heard a couple people saying it will work, similar to how you can "sharpen" knives by running their edges against each other.
@@danielnapast4955 he was definitely joking, problem is that this joke has weaseled its way into the shops of some people who are unaware and have gone on to repeat it. Whether they said it as a joke or not it was passed along so often that at some point certain people began to believe it.
It is always said sarcastically by some old salt claiming that he sharpens his files by throwing them in the drawer with the others and they sharpen each other, meaning, ...he doesn't sharpen his files. I would bet that some new blood heard it and could not identify the tone. Same guy that spends 6 hours of his shift looking for the blinker fluid and can't figure out why everyone is giggling under their breathe.
Its sarcasm....sheldon.
You can use the end grain of that 2x4 to clean the file, much like you used the flattened copper tube. I have been cleaning my files that way for forty years, works well.
thanks for the tip
Pretty good bet that guy knew Mr Murphy of Murphy's law fame.
Mr Murphy used to work on the rocket sled.
After a very expensive rocket sled test where he didn't get any test data, he is purported to have said "If there's a right way and a wrong way to hook something up, sooner or later someone will hook it up the wrong way."
Interesting bit of trivia.
Thanks,
John
+John Bazaar
Thanks for your comment
As a licensed tool and die maker I can tell you that you did not sharpen your file. You simply removed material that had loaded up in the gullets of the teeth. A "loaded file will not cut, so removing that material will make it cut better. To sharpen a file you must remove metal. Files are very hard but being the same hardness means that rubbing them against each other (as in a drawer) will actually dull the cutting edges. A good way to prevent loading when cutting soft metals is to first rub chalk onto the file. This will prevent the soft metal from sticking in the gullets of the files cutting teeth. The teeth on a worn file look shiny instead of dull. When THAT happens, throw it away. There is NO way to resharpen it.
It really dose sharpen the file. Give it a try, you have nothing to lose. I promise you, you will be surprised.
One side note the file must be dull not damaged to work. :-)
If the teeth are rounded and the acid strips away an even amount over the entire surface area, it will make the teeth more narrow and remove the rounded tops, therefore making it sharper.
I was wondering about that as well, if it removed the material evenly, if that wouldn't keep the edge intact.
If this were true then you could take a razor sharp knife and put into acid and expect it to come out razor sharp but it would actually erode the thinest part first which of course is the sharp edge. Working as a toolmaker since the 1980s I have a strong background in metallurgy and how metal can be sharpened or lose its fine edge. As said earlier, the file may seem sharper but this only because acid has removed material from a clogged file not by making the edges of the teeth sharper. A clogged file will not allow teeth which are still sharp to cut.
its going to remove the sharp tops faster than it removes the rounded tops.
Hi Dale, nice tip, but using the file without a handle... you were specific about safety with acid & wearing protective gear but not mentioning file handle ... tut, tut,
Yeah Excellent information. I never considered being able to sharpen? a dull file. I have always discarded files when they wouldn't cut anymore. Thanks so much. I will certainly be giving this a try!
Have fun I know you will like it
I worked in a machine shop and we would just get a new file. We had a thousand files at least. When industry makes a lot of money they do not care. The other parts of the video are right on. Keep up and make more V's.
Looks like it works OK. I would be interested to see what a high powered microscope on the tooth profile on the file looked like before and after. If it just cleans the file, it would be useful enough but if the effect of the acidic bath alters the tooth profile it may be even better.
I just put that question in. I'd like to see that too. Maybe someone has done that already on YT. We should look for it.
I belive is called chemicaly sharpening, is a method used to sharp fising needles, razor blades, because it takes less time and is cheaper than going through multimple grits of sanding materials. They just sharp them up to a point, then dip them in accid, this will disolve the steel and leave the edges as sharp as steel can be. I wouldn't say is better because it also weakens the teeths of a file, and if you do this multimple times, i would say more than two times, it will affect the flatness of the file and it will eat the teeths. Is good method, i never tried it, but i played with accid to remoe some rust. For old files, is better to give this treatment then throw it away. And old files can be turned into other kind of tools, such as chisel, or marking knives.
A clear explanation of this process and several similar metods can be found at page 235 of Workshop Receipts: For Manufacturers and Scientific Amateurs, Volume 2. It's available free from Google books.
thanks for sharing this information. :-)
Happy to. When I first learned about the process from Jim Thompson on the Old Tools Mailing List I was a bit skeptical. It sounded too good to be true. Jim had never steered me wrong so I tried it. It worked. I had some growing pains learning how long to leave the files in the bath. A couple of Swiss cheese files convinced me that forgetting them was a sure route to failure. :-)
When I knew it worked and had finalized the process I decided to share it. I expected a hundred or so people that I regularly corresponded with on the list would be interested. Little did I know it would be one of the most viewed videos on my channel.
Then along comes Colin Riley on your channel. Next thing I know your video is at a quarter million views and climbing. My video is at sixty thousand and climbing, and my channel has passed three quarters of a million views overall.
Colin may be a pain but I really appreciate him starting the whole "It's only cleaning" meme.
The machine shop I used to work at sent our files out to be resharpened, it did a good job but you could still tell the difference between sharpened and new. They always came back a darker color than when they were sent out, now I know why (acid etching). Thanks for the info i will be hunting for drain cleaner and baking soda next shopping trip!
+Davlok
You can get the drain cleaner at Lows
I was taught this same method back in the late 60's by an old machinist who was still using his fathers files.
excellent lesson thanks..
Thanks
B
i was taught that if a flie dose not cut clean it with a file card .
but how dose acid which eats /erodes material actually sharpen .
as a file is hardened you would need a diamond sharpener
more important never use a file with out a handle. you are showing your true professionalism
please correct me if im wrong so i can throw all my qualifications in the bin
If you're the type that always grabs the file brush when they grab a file, you may never need to do anything further. This is for when the rust and gunk build up so much that the file card won't cut it, (while a file brush removes chips well, it doesn't do such a great job of polishing the grooves). As soon as you remove the oxidation from steel, it comes back. If the rust gets to the point the brush can only remove the rust from the very edge you'll find yourself using the brush more often. Just the act of using the file helps to clean the edge. Like I said, using the brush often means you might never have a problem. Rusty garage sale files? They need more than a brushing. The deep groove in a file is just as important as the cutting edge - the chips need a place to go or they act like bearings - not good if they are full of rust.
During use the tips of the file teeth wear away. That is normal wear. As the file wears it begins to skid over the metal rather than biting in. At that point it is a viable candidate for either hydro-honing or acid etch sharpening.
If the file is abused, banged around in a box full of tools, run against hardened steel, or dropped so that the teeth are broken and chipped they are not candidates for hydro-honing but only because of cost. They can still be acid etched. Without shipping costs and the time involved, if you are able to save only one in three it's a good deal. Perhaps most of the file is okay with just one side screwed up, or one end. With no appreciable cost involved, what do you have to lose?
If the file is a little rusty or dirty, use a file card or perhaps a soft steel bar, like I use in my file cleaning video, to scrape the rust and dirt out of the teeth.
Something I haven't noticed in these discussions is any comments on pinning. It's not the topic of the video but if we talk about cleaning, as nearly every post has mentioned, then describing the things that create the need for cleaning should be defined. Pinning is when the gullet between the teeth becomes filled and stops the tooth's cutting edge from contacting the surface.
If you are having this problem then cleaning will be an endless effort. It is caused by the teeth being too fine for the chip load. Go to a larger file with bigger teeth.
Duncan Harris: I think one reason to throw your qualifications in the bin is that they should have taught you to look into statements/ processes offered on this video before posting negative statements of your own, just try it, then you can post a valid comment! (I would have thought that anyone with any kind of qualification would not be an armchair critic).
tell me where the shapening comes in ? as pointed there is an etching effect am i not the only one question. but as a professional my kit is looked after ( may be a snob having separate compartment for tools so they don't get damaged ) when you have worked in motorsports doing silly hours come back an then call me an arm chair critic
Duncan Harris As soon as you clean steel it starts to oxidize. An oxidized edge isn't as sharp as a clean edge. Whether we sharpen the edge by rubbing, scraping, grinding, or chemically treating the oxidation away - if the edge is sharper as a result we have sharpened it. Clean tools are always sharper than rusty tools, even if the difference is negligible.
It doesn't matter how organized and clean you keep your tools, when it comes to cutting edges made of steel, they will cease to work at an optimum level the longer they are exposed to oxygen. Leave a file in the tool box for 5 years, and even if it was spotless when you put it away, it's going to take some work to clean up. Will it need an acid bath? Maybe not - but if somehow sat in water a couple of those winters it will - and a file brush won't be the tool to use. Don't worry about it too much. I'm sure somebody out there has a tank hooked up to their toolbox to keep it flooded with nitrogen, I don't.
I wouldn't be happy until I know how, and why, it works.
Thanks for a very clear and simple demonstration. This is the one I will follow.
To all you doubters (which I also was) ... this actually works - I've even checked under the microscope..
thanks for your comment :-)
Sure. It works great at cleaning out the teeth. Not sharpening though.
No shit cleaning a rough surface so clogged full of shit it feels smooth makes a surface rough again.
But that’s not sharpening its cleaning
I use electrolysis to sharpen files. Works well !
I have too. I like it as a cleaning steps before the acid bath.
***** I also did with the acid but hot phosphoric acid, really effective. Keep up the good work, your videos are very interesting.
Electrolysis uses much less materials. Only table spoon of baking soda is all you need.
How is it done?
Yup . Add some degreaser to the bath , and it'll take off all the baked on stuff that comes of buying used files . Found that 12v 6a will pit a file very quickly .
I did think you could have elaborated on exactly what happens when you add water to acid, but then, people got the right to do that sort of stuff. 😃
A nice little video, I'll give it a go. Thanks
Found this one in PM Shopnotes and have used it, works ok. Liked the copper tube, I'll have to try that.