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Rick
12-13-2007, 12:21 PM
This is a good way to sharpen chisels and plane irons.....

Condensed Version or 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).


found on th www

MrW32
06-14-2008, 10:38 AM
It works with knives, too, but one seldom really needs a knife that sharp!

You can also use a stone for the rough work and only finish with the paper on the glass.

Great stuff.

-Patrick

Drawbar
06-20-2008, 05:34 AM
I use the method all the time as a woodworker, often going up to 2000 grit sandpaper so that I can get a nice, crisp edge that will slice the hairs off your arms.

I use a sheet of locomotive glass that is 3/4 of an inch thick and bullet proof that makes glass in the shop much safer and long lasting. Heck I even built a special drawer that pulls out from my bench so that I can quickly and easily sharpen my tools. It works great.

http://www.railroadmachinist.com/sitebuilder/images/Scary_Sharp_Drawer_Open-452x335.jpg