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From: arno@utu.fi (Arno Hahma)
Newsgroups: rec.guns
Subject: Re: Best Knife Sharpening System is WHAT???
Date: 28 Apr 1995 23:00:27 -0400
Organization: University of Turku
Lines: 51

In article <3nhbjm$2cl@xring.cs.umd.edu>,
Tim Lau <tlau@orion.oac.uci.edu> wrote:

#1. Lay your knife edge flat or almost flat against a coarse stone.
#2. Scrub the side of the blade until you can see a burr on the edge of
#   the edge of the blade (on the top side) running the entire length
#   of the edge.
#3. Repeat for the other side.
#4. Then, using a fine stone and about a 25 degeree angle (this will
#   vary depending on how you are going to use your knife), make
#   alternating strokes from the bottom of the knife up to the tip.
#   An edge guide would be very useful.

This is how knives should be sharpened and this is the way I
always do it. Result: I could shave with the swiss army knife I am
carrying in my pocket.

The list ignores a couple of hints that help make an even sharper
edge:

5. Use a _good_ stone. The best I have found this far is the Hard
Arkansas Oilstone. At least Norton sells and makes them. The Arkansas
stone is really fine, it should be used only to finish the edge.
Coarser grinding should be done with a silicon carbide stone or
equivalent.

6. The final polishing is best done with a leather belt. I use the belt
I am wearing. A tiny amount of some extremely fine polishing powder can
be spread on the belt (you only need to do this once), I used <100
nanometer aluminum oxide dust. The polishing powder speeds
up the process; it'll work without as well.

When you polish the edge after the finishing stone, the result will be
equivalent to a razor blade edge. The technique is similar to what
the barbers used to sharpen their razors.

#but SHARPENING is another science.

That is right! Leather belt makes very sharp edges, but even sharper
(about 10 times better) can be made with a copper plate. Microtome
blades (steel ones) are sharpened by holding them gently against a
slowly rotating copper disk. If sharper than that is needed, then
metals are hardly usable any more. Glass, ceramics and diamond are
used, as metals lose their edge fast in the atmosphere. Besides, metals
are not hard enough to hold an ultra-sharp edge anyway.

#Tim

ArNO
    2

From: Robert Bastow <teenut@Nospamhotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Q: Bobbiting on the lathe
Date: Sat, 08 Jul 2000 12:06:41 GMT

Bucky Goldstein wrote:

> Robert Bastow <teenut@Nospamhotmail.com> wrote:
>
> > Bucky Goldstein wrote:
> >
> > > That's pretty much how I sharpen all my tools, but I use an India
> > > stone and then an Arkansas stone, and I use 'em dry.  It's okay
> > > to use oil for rough stuff, but for a nice edge it's best to hone
> > > on a dry stone.  Oil suspends particles of grit & metal.  Push a
> > > blade through that and it's like driving it through a pile of
> > > sand.  Better to clean the stone with solvent, then hone the
> > > tools dry -- makes a very nice edge.  Never oil a whetstone.
> > > (Most people disagree with me on this, but they're wrong.)
> >
> > I would like to see your authority on this!
> >
> > As in..where the f**k did you get THAT gem of misinformation?
>
> Well shoot, brother 'nut, let's not do it that way.  Not much to be
> gained by comparing authorities (though mine are actually pretty good,
> and I'll tell you about 'em if you think it matters).

Yes it matters! I DO need to compare.

You show me your's..I'll show you mine!
But as I often say.."Don't bring a knife to a gun fight"!

> But.  The conventional wisdom of honing is false.  You get a better edge
> with a dry whetstone than you do with oil.  I'm willing to be corrected,
> but it'll take some doing.

No doubt about it..a dry whetstone will put a shinier finish on your edge than a
wet one.  A fact that is used as an accepted technique with WATER stones. They
are often used beyond the point where the available water and the slurry it
forms, dries out and continued honing provides a final finish.

But don't confuse the characteristics of a water stone and an India or Arkansas
"oil" stone..they work and are used in quite different ways.  On the water stone
the surface is considered a consumable part of the process..it is repeatedly
"sacrificed" in the use of the stone.  Not so with a hard arkansas stone..like a
diamond hone, they are expensive and difficult to resurface.  Every attempt is
made to keep them free cutting, clean and "open" DURING the honing process.
Your use of a dry "Oil" stone is destroying the cutting features of the stone
which will need to be frequently (and expensively) renewed or replaced.  It is a
quick fix, "dirty" way to get a good edge..It certainly won't work for long if
extensive honing is required (have you tried sharpening many knives with a dry
stone?)


>Let's do it this way: what do you think oil
> adds to the honing process?
>

That ain't the way this or any other discussion forum works Bucky..I asked
first!

But, for what it is worth..it adds a not unimportant factor, like LIFE to the
(Usually) expensive hone, prevents clogging of the pores and washes away debris
so the stone can keep on cutting.

BTW when you say "Oil" I do hope you understand that 10W40 is not the correct
"oil" for honing. It will simply clog the surface of the stone. Honing oils are
very light..I use straight kerosene.  I keep the "Ready use" slip stones on my
bench in a jar of kerosene..these being the ones I use, not just for touching up
tools, but for "Hard Fitting" of tool, die or gun parts.  There are, perhaps, a
dozen different shapes, types and grades in that jar..all with their specific
uses..and ALL too damn expensive to want to screw them up!

Respectfully,

8^)

teenut


From: Robert Bastow <teenut@Nospamhotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Q: Bobbiting on the lathe
Date: Tue, 18 Jul 2000 01:34:59 GMT

Ted Edwards wrote:

> > But I do differ with you on the oil/longevity issue: done right, you can
> > dry-hone for a long, long time on the same stone & not wear it out.
>
> You've been blowing that horn for too long and it's going flat.  Believe
> it or not, other people read and even look through microscopes.  You're
> full of it on that issue so lay off.

I couldn't have put it better meself Ted..The only thing I dry hone on is a
folded newspaper!!

Try it some day when you want that "Scary Sharp" edge on a knife or razor..Good
for a swift touch up on a field knife too.

teenut


From: Ted Edwards <Ted_E@bc.sympatico.ca>
Newsgroups: rec.crafts.metalworking
Subject: Re: Q: Bobbiting on the lathe
Date: Mon, 17 Jul 2000 23:10:35 -0400

Robert Bastow wrote:

> I couldn't have put it better meself Ted..The only thing I dry hone on is a
> folded newspaper!!

Never tried *that* but, rest assured, I will.  Considering the abrasive
qualities of paper it should certainly work.  (Look at a piece of paper
while holding my wife's sewing scissors and they might just get used on
certain parts of one's anatomy!)

Ted


From: Robert Bastow <teenut@Nospamhotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Q: Bobbiting on the lathe
Date: Tue, 18 Jul 2000 02:20:26 GMT

Bucky Goldstein wrote:


> That slurry (call it whatever) is the problem.  You can get a sharper
> edge if it's not there.  (I wonder whether anyone here will actually
> _try_ it.)
>

I already stated that a dry stone WILL cut faster...But for a limited length of
time before the exposed cutting grains become blunted and the pores become
jammed with METAL particles.

No amount of solvent will remove/restore it's cutting qualities when that
happens.  You have to physically remove the top layer of the stone to restore
its cutting qualities.  Good stones are too expensive to waste rapidly with such
"quick and dirty" abuse.

teenut


From: Robert Bastow <teenut@Nospamhotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Q: Bobbiting on the lathe
Date: Tue, 18 Jul 2000 01:25:19 GMT

Ted Edwards wrote:

> Robert Bastow wrote:
>
> > "sacrificed" in the use of the stone.  Not so with a hard arkansas
> > stone..like a diamond hone, they are expensive and difficult to
> > resurface.
>
> Not just expensive, unobtainable.  I have a hard Arkansas (50 yrs old)
> that is almost as fine as my black hard (25 years old).  This material
> is running out (has run out according to one source) and the quality of
> what's left is not as good.  So far I've not been able to find a
> replacement that's as good for *really* serious honing.  Listen to
> teenut if you want to have a stone that cuts quickly, stays flat and you
> can pass on to your kids in good condition.
>
> teenut:  Isn't kerosene a bit too light?  My 20 yr old bottle of honning
> oil is getting low and I'm interested in whether there is a common
> alternative.
>
> Ted

I have a couple of bottles of honing oil I picked up at a garage sale.  I was
curious about it because I had never heard of it before coming to the USA.  In
England I always used kerosene (paraffin in UKSPEAK), everything else was sure
to "cure" or air dry sooner or later and require the stone to be boiled out in
kerosene to restore its cutting qualities.

I would offer to mail the "Honing Oil" to you..but I won't, as a I think I would
be doing you a disservice!!  The stuff is FAR too thick and DOES dry,
eventually.  In an emergency I would go to something THINNER than kerosene
rather than thicker..like WD40 or even water.

On the hard Arkansas I always carry "in the field" for touching up my knife
blades, I always use spit!!

teenut

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