File work; A few words.

Dean,

An excellent tutorial on filing - TVM. :bow: :bow: :bow:

Marvs comments about safe edges add a little more to this dying art.

My 2 bob's worth is how I was taught to hold large thin flat surfaces which wont hold in a vice without bending or the file can't access the work because of the vice jaws.

Take a block of wood say a minimum of 1/2" bigger all round than the surface to be filed. Place the workpiece in the centre of the block of wood and lock it in place using small brads. When fitting the brads around the edges ensure that only the shank is touching the workpiece, the heads should remain above the workpiece. Filing to size removes the heads of the brads and the work remains securely locked to the wooden block, which is held firmly in the bench vice.

Best Regards
Bob

Everyone, thanks for the remarks on the write up. I'm happy if someone is able to get something from this.
Really appreciate the additions made thus far, too. There are quite a few aspects to this filing thing, many of which I don't think of unless I'm actually doing it. Putting experience into words, I invariably leave things out.

I had this picture of a safe file made up last night, but somehow I erased it and it didn't get put into the original post, so here's another one. You can see the safe edge on one side of the file. No teeth there, as Marv was describing. You can file to your hearts content in a corner without being concerned about messing up the adjacent surface;



You can make your own safe file, as has been mentioned, but you can buy them too. When you buy one, you get a nice smooth safe edge. You can indeed grind a good safe edge, if you're good with a grinder. That's a whole 'nuther subject.

Thanks again for all of your replies!

Dean

For those like me who like to read about stuff.

http://books.google.com/books?id=Dl...xy_is=&as_brr=1#v=onepage&q=file work&f=false


Lots of history and manufacturing how-to's along with info on various types and uses for files.



Kermit

If I may add some to an excellent post...

If you want to file a plane surface and have no shoulders in the way is convenient to file at 45 degree both way to get a cross hatch pattern.
When roughing the 90 degrees change in direction works across the previous ridges and makes the work go faster.
You see better where you are cutting due to the cross hatch marks contrast.
It is a bit easier to reduce the crown (high in the center) that is so easy to develop unless you are really attentive and skilled.

To finish you can use a triangle file, the taper has a convex shape and lets you control the metal removal in the center of the surface without touching the edges.

Awesome Info Dean!!!

Now i know why my file does not work so well anymore... :big:
Off to the stores this weekend to replenish supplies and apparently some chalk too!

Thanks for the most useful info!
I cannot remember the last time i used a file, but i believe it was way back in school in woodwork class... ;D

First class thread Dean, thank you, I've certainly learnt a lot ........... I did know about the chalk, and have used it for years : ............ but the tips you have shown are just priceless 8)

respect CC

Wow lots of info here. I scanned the posts, impressive. I will add a couple of comments . Hopefully not repeating. I am pretty comfortable with a file . When I was in aircraft sheet metal the file was pretty much the tool of choice and the only tool allowed for most of the work. Shears were used for general shaping then files and silicon carbide paper. all edges had to be finished scratch free to 600 grit. But files did most of the work.
Even in the world of cnc there is still a need at times for hand finishing. One of my former careers was what most folks here would call pattern maker. This for for 40ft +- Motor yachts . All parts of a new model yacht had to have a pattern to make a mold. When I first started a the job all work was done by hand. things were built from scratch then hand finished. 6 years later the bulk of the work was a quick throw together sprayed with foam then shaped by CNC. But the final shape was still hand done.
I guess the point I am making here is the hand and the eye are the most used and valuable tools. Also do not underestimate the value of files and sandpaper.
Tin

Dean

Thanks for the tutorial and for making filing seem much more respectable. I have felt at times that resorting to the file was an admission of poor machining but I do it a lot. The tip on using chalk to fill the file rings a bell from deep in my memory but I have never used it. I will now.

I've seen file cards or brushes in the catalogs but I just use one of those cheap brass toothbrush shaped things with good results, particularly with aluminum which seems to gum up the file on every stroke. AHA! I should use chalk!

Another technique that I have found usefull, particularly with small pieces is to put the file in the vise (with soft jaws) and grip the part with a small machinist clamp that lets me control the part as I draw it over the file. If the part is aluminum, I sometimes put a few drops of turpentine (Pine Spirits?) on the file.

Here is a picture of using a file in the vise as a preliminary step in lapping the valve for my Spider Engine. The valve cover is aluminum 1.75" diameter with 1.5" bore turned on the lathe. Two brass pieces, the eccentric and the slide ring rotate in the bore and all three pieces must be dead even so that they make a good seat on the face of the Head plate. I put the brass pieces in the valve cover and usse a short piece of brass rod through the bore of all three pieces to help control the assembly as I draw it over the file. The aluminum valve cover is wider than the file but I rotate it a few degrees on each stroke and take very light cuts until I get bright faces on all three parts. I then flip the brass pieces over in the cover and take a few more strokes, again until I get shiney faces.

Final lapping is done with the valve cover and all components screwed together with the head plate. The eccentric is fixed on the drive shaft so that it can be turned in the bore. I mix a little turpentine and Brasso and put some in the valve cavity and turn the shaft in the lathe while holding the plate still as I screw the cover down tightly to the head plate. After a minute or so, I take it apart and wash good with soap and water and its good to go.

Jerry

I use a small chip brush for cleaning my files. The end of the hardwood handle does a great job of confirming to the teeth on the file and pushing out chips. I cut the bristles down to about 1/4" and brush the file down after I am done with the other end. Always works for me!

So where do I find this hard chalk?

Twmaster said:

So where do I find this hard chalk?

Click to expand...

Kids sidewalk chalk works well.

Try soapstone, sometimes called Welders chalk.

websterz said:

Kids sidewalk chalk works well.

Click to expand...

Sidewalk chalk is pretty easy to find at discount-art and toy stores around here. Sometimes in the toy aisle of the supermarket

I use sidewalk chalk too, Mike. The kind used for blackboards will also work, but it makes more dust and doesn't seem to stay in the file teeth as well, for me.
The sidewalk chalk comes in big fat sticks that will fill a file in just one or two strokes. Comes in colors, too!

Dean

I have never tried using chalk. Now I'm going to have to try it just to see how it works.

Usually, I grab a brass toothbrush (at least that is what it looks like) whenever I grab a file. I file a little, then set the corner of the file tip on some wood and brush the file clean. Sometimes that means every few strokes, sometimes a dozen strokes, depending on the material I'm filing and how fast it loads up the file.

Russ

What an excellent thread - so much good info. - especially for those of us who are less experienced.

I have never had much success in using a file card/brush in removing debris from file teeth - but always had a good result using a scrap piece of brass sheet (like a "comb") as Marvin said back on one of the earlier pages of this thread - well worth trying.

A dumb question maybe - but in several articles published in mags. on filing, it always seems to be recommended that files must be separated into those used on brass etc. and those used on steel. Do not use a brass-file on steel and vice-versa.

Does anyone have an opinion on this - whether this is good practice - is it worth building up two sets of files for ferrous/non-ferrous work?

Peter

standard practice would be to 'retire' a file used on cast iron and alloy steel to working on softer steels, then brasses and aluminums, finally moving it to lead solder working

Excepting that the cleaning requirements are greater - there is really nothing to prevent the use of one file on both metals except widely held opinions

Peter,

I am of the opinion that having files separated for brass, steel, etc. is unnecessary. However, files used on hard or abrasive materials should be kept just for those materials and nothing else.

Cast iron is rather hard on files, stainless steel, tool steels, and pre-hardened can be as well. The files used on these materials wear, and although they can still be used for softer materials, they won't cut as well as they should. Files used on harder materials can also have chipped teeth, which only adds to the problems with cleaning, as pins aren't as easily removed, but are easily formed.

CRS, HRS (with scale removed), low carbon steel, etc, shouldn't cause any problems with a good file that is kept clean and used properly. As mentioned, dragging a file backward over your work will dull it.

I don't recall seeing a mention of handles. File handles are a must-have, and though I have to admit that I will occasionally use a handle-less file, it is not good practice to do so. Your control over the file is much better with a proper grip, and a file tang can be hazardous to your health, especially when filing lathe work. The "proper" way to file lathe work is left-handed with the handle held in the left hand (obviously) to keep from reaching over the chuck. I have never done it this way, finding it too awkward, and in 25 years of working in machine shops I have seen possibly two people filing left-handed. Either way, when you are filing your lathe work next time, take a look at where the tang of that file is pointing and imagine where it will end up if the chuck or the work drives it back at you.

Kevin

joeby said:

I don't recall seeing a mention of handles. File handles are a must-have, and though I have to admit that I will occasionally use a handle-less file, it is not good practice to do so.

Click to expand...

And less of a chance that the file end will be driven in your hand while working on the lathe...

Hi all
Nicely done thread Dean, I have picked up a few tips here. When filing on a lathe even with a file handle I find myself staying to the left of the file as much as possable.I am vary careful of the chuck when reaching over it and check things often to see were I am at. Here is a link to an article a friend sent me I thought may be intresting to some on sharping files I have never tried it.
http://swingleydev.com/archive/get.php?message_id=157695&submit_thread=1

Thanks for a good post
Dave