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Dan Dresner
 
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Default Scary Sharp revisited

I just finished sharpening my first chisel with Steve Lamantia's Scary Sharp
method and now stand before in stunned testimony: this technique is
life-altering! I now have an ordinary, off-the-shelf bench chisel (Stanley,
for Pete's sake) that is at least as sharp as any razor blade I've ever
used. It's going to take a month for me to regrow the hairs on my arm after
"testing" the edge over and over again. I'm not kidding, folks: it slices
them off just by pressing the edge - lightly! - against the base of *a*
hair.

(I know, I know - I need to get a better life, but still....)

The only change to the system that I made was to add a final polishing with
crocus paper, which seemed to improve the sharpness somewhat over the
2000-grit level.

DanD

For anyone who doesn't know what the heck I'm talking about, here it is:

**********************************************

Condensed Version of How to sharpen a plane blade with sandpaper.

Mercilessly butchered into a Condensed "How to" Version by J. Gunterman from
the Original by the Steve Lamantia.

To lap the back behind the cutting bevel:

Use a very light coatings of 3M "77" spray adhesive to temporarily glue
small 1-1/2" x 3-1/2" rectangular pieces of sandpaper along the edge of a
sheet of 1/4" plate-glass.

The paper to use is Aluminum Oxide in grits 50, 80, and 100, and Silicon
Carbide (wet-or-dry to you lay people) in grits of 150, 180, 220, 320, 400,
600, 1200, and 2000. The plate glass should be placed with its edge flush to
the edge of the workbench. Grits can be skipped, if desired, but more time
on each grit will then be required to fully remove the scratches from the
previous grit. Using the gradual progression as listed, however, will
require only about a minute or so with each grit."

Lap the end one inch of the back of the iron on each grit in turn. You could
use it wet or dry.

About every ten seconds or so, stop and brush off the sandpaper with a whisk
broom and wipe the blade off on your shirt.

About ten minutes after starting, you should have gone from 50 grit on up to
2000, and there will be a mirror finish on the back of that iron the likes
of which must be seen.

Then jig the blade in a Veritas honing jig or go it by hand--

Clamp the blade down in the Veritas blade-holder device, taking care to have
the bevel resting on the glass perfectly along both edges. Adjust the
microbevel cam on the jig up to its full two-degree microbevel setting --
and hone away on the 2000-grit

Flip the blade over on the sandpaper several times, hone and lap, hone and
lap, each time gentler and gentler, to remove the little bit of wire edge

The resulting little thin secondary bevel should be quite shiny by this
time.

Remove the blade from the jig, and perform the "shave some arm hairs off"
test, or the sharpness test of your own choice.

Of course, the ultimate test of a plane iron's sharpness is what it does on
wood.

When it is all done, peel the sandpaper from the glass and throw it away.
Then, scrape the little bit of residual adhesive from the glass with a razor
blade, a quick wipedown with acetone on a piece of paper towel, and the
cleanup is done in a minute.

No oil, no water, no mess, no glaze or flatness problems to worry about, and
a cutting edge that is Scary-Sharp (TM).