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From: Robert Bastow <>
Newsgroups: rec.crafts.metalworking
Subject: Re: How to file aluminum...?
Date: Mon, 23 Aug 1999 01:56:02 -0400

The problem you experience is common to all files on all metals...Its "official"
name is "Pinning"

Conventional wisdom is to rub the file with chalk..but in 40 plus years of
filing I haven't found this to be worth a tinkers cuss!!!

A file is a cutting tool like any other, and, like other cutting tools, responds
to the correct lubricant.

Kerosene will work..but is IS SMELLY!!  I use good 'ole WD40 because it is cheap
and handy to apply.

On real heavy duty filing, particularly of tool steels etc., I take the trouble
to fetch my suphurised oil squirter from the lathe.

Even this treatment will not, totally, prevent pinning.  Get yourself a good
"file card" with stiff bristles on one side and wire bristles on the other,
and USE it frequently.  Don't wait for the problem to arise..but get in the
habit of brushing with the bristles every few strokes.  Even EVERY stroke on
critical finishing cuts.

If the "pins" won't come out with the card, then get a 3/4" wide strip of 16
gage steel or brass...Fix it in a handle and keep it with your files.  To use
it, file or grind the end dead square and first rub it a few times along the
length of the teeth, up near the tang where they are single cut.  This will
establish "teeth" on the steel that mirror the teeth on your file.  Use it to
push out pins and other grunge, working carefully, always in the lay of the

New files benefit from a gentle break in period, during which fragile burrs are
worn off, rather than snapped off..taking a chunk of tooth with them.  At the
same time the gullets become polished and less likely to pin up.  I have found
that this process can be speeded up by gentle brushing on a soft wire brush on
the grinder.  Naturally you always work in the direction of the tooth gullets.

A file that has not had this break in process, but is pushed hard, straight out
of the box, will have a short but nasty, lifetime tendency to pin badly!!


Bill Richman wrote:

> (And if anyone says "Under 'A'" they get a free set of aluminum jockey
> shorts, poured in place... ;-)
> I'm having a heck of a time with my files "gumming up" with aluminum.
> When I file a casting, it keeps going "rasp, rasp, rasp, rasp, HACK";
> little globs of aluminum stick in the teeth of the files, and on the
> next pass if I don't notice and stop in time, they leave these lovely
> furrows across the almost-smooth surface I'm filing.  I don't recall
> having this much trouble early on when filing my castings, but I don't
> think they alloy has changed.  I've tried two different cross-cut files
> and a mill file, and they all do the same thing.  The mill file takes
> longer between problems, but eventually it, too, succumbs.  One of the
> cross-cut files is a few years old, and the other is brand-new.  I've
> seen comments about dipping the files in kerosene (first, gotta find
> somewhere I can buy it, and second, gotta convince myself the smell is
> worth it.)  I've also seen something about files with curved teeth;
> haven't been able to find one at any of the hardware stores, and haven't
> made it to the industrial tool store before closing time in the last 10
> days.  Just poured the head stock for my Gingery lathe, and don't want
> to hack it all up trying to clean off the fins.  Any suggestions?
>       -Bill Richman (
> - Home of the COSMAC Elf Microcomputer
>        Simulator, Fun with Molten Metal, Orphaned Robots, and Technological Oddities.

From: Robert Bastow <>
Newsgroups: rec.crafts.metalworking
Subject: Re: Files
Date: Fri, 30 Jun 2000 06:06:45 GMT

harrop wrote:

> Can anyone fill me in as to the carbon content of hand files as well as a
> run-down on how they are manufactured? Thank you in advance. Rob

Good Quality modern handfiles should run about 1.1% carbon.  Poor equality may
simply be case hardened mild steel..this applies especially to imported rasps.

Files are stamped from bar, straightened, annealed. surface ground and then the
teeth are cut by chisel type cutters in automatic machines.  They are then heat
treated, inspected and packed.

Not too long ago, files were being hand cut by File Cutters, one tooth at a time
with chisel and a special file cutters hammer while resting on a lead block.


Newsgroups: rec.crafts.metalworking
From: (Russ Kepler)
Subject: Re: Files
Date: Fri, 30 Jun 2000 04:56:03 GMT

In article <8zU65.2181$>,
Robert Swinney <> wrote:
>Files are quite high in carbon content, although the exact percentage
>escapes me now.

Older files are basically W2.  Newer files are being made with a
simple carbon case on a lower carbon steel core.

Russ Kepler                                    

                      Please Don't Feed the Engineers

Newsgroups: rec.crafts.metalworking
Subject: Re: Cleaning Files
From: Robert Bastow <>
Date: Mon, 02 Aug 1999 05:39:33 -0400

The file cleaner doesn't need to be as soft as brass or copper!!  Remember that
files are "Dead Hard"...60-62 Rockwell!!

My file "comber" is a strip of 16Ga Mild steel, 3/4" wide.  It is so successful
that it now sports a custom turned cherry wood handle with a chic polished brass
ferrule and occupies acoveted slot in my file rack.

By The Way..The old saw about chalking files to prevent "pinning" is the biggest
heap of "dump" ever perpertated on unsuspecting metal shifters.

I also recall reading a couple of times that a file, ""contaminated with oil
would never cut again!!


A file is a CUTTING TOOL!!  

A Linear Broach!!!

A "flat" Milling Cutter!!

I spray my files with WD40..Before,  during, and after "filing for effect"

Not only does it prevent rusting (the file's biggest enemy)..BUT...It almost
totally eliminates pinning, promotes easy, fast and smooth cutting..AND..With a
bit of practice, leaves a surface finish that rivals that of surface grinding!!


Go get yourself a new, SHARP, file of good quality..Nicholson, Grobet,

Treat it like GOLD!! (Hey...Try MAKING one!!)

Break it in for a coupla years, filing only Non-Ferrous materials.

Spray with WD40 and get down to some SERIOUS filing...Say a double rifle action
body from solid steel..."Striking" (draw filing) a set of Purdey
barrels...Sinking, fettling and detailing a mold cavity before handing off to
the Polishers....

When finishing, wipe the file with the ball of your thumb, against the "cut",
every few strokes.  Brush the file clean and re-spray every dozen or so...Enjoy
a new dimension in metal smithing!!

Brush her down, spray her down, and "Put her up wet!!"

I other words, treat your files like any other precision tool in your shop.
Learn the skills and the art of filing...

The back wall of my bench sports a rack of over fifty files..some as old as I
am????  They get a daily workout and good treatment..They will see my lifetime
out..and a couple more generations too..if handled right!


Thinking about it.  I do not recall EVER, walking into a store and actually
BUYING a file!!  The hundred plus I have, have just been "Accumulated" over the
years!!  Curious Huh?


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