Getting a Knife Razor Sharp With Sand Paper




Introduction: Getting a Knife Razor Sharp With Sand Paper

About: recently unemployed, I like to make things just to see if I can,

I this instructable you will learn how to sharpen a knife with sandpaper and a strop.

materials required
a knife
sandpaper 800, 1000, 1200, 1500, 2000, 2500
leather strop
stropping compound
piece of glass ( I used one out a picture frame that is 3/32", but the thicker the glass you can find the better)

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Step 1: Know the Methods to Stroke the Blade

In the first method you hold the cutting edge in the direction of travel as indicated by the green arrow

In the second method you move "up and down" as indicated by the green and blue arrows.

In the third method it is a combo of the first and second methods, where as you move "up and down" (as indicated by the green and blue arrows) you also move against the cutting edge at the same time (as indicated by the red arrow).

The fourth method is quick back and fourth motion as indicated by the green and blue arrows.

What ever method you choose you need to flip the blade over after 2 or 3 strokes.

It doesn't take a lot of elbow grease, time, working the blade to get it sharp.
It take maybe about 10 strokes on both sides of the blade total on each side of the blade on each sheet of
Experience will tell you what it takes. and actually if your blade is just dull you may not even need 10.

If you want to get the knife polished, use more strokes and successively more strokes as you work up in grades of sandpaper and you can achive an almost if not a mirror polish when you strop it.

Step 2: 500-2500 Sandpaper

start with the 500 sandpaper.
place the sheet of sandpaper on the piece of glass.
put some water on the on the sandpaper
place the blade flat against the sandpaper, see the crude paint shop pic. The blade on the left is a single angle and the right one is a 2 angle knife, the light blue section is the cutting angle.
 Hold the blade flat against the sandpaper. Note that the red is the glass and the brown is the sandpaper.
If there are 2 angles on the knife try to match the cutting angle (this takes practice but  you will get the hang of it)
Now proceed with your chosen method of stroking the blade and and continue the same from 500 sandpaper to 2500 sandpaper.

Step 3: Strop the Blade

The last step is to stop the blade.
Rubb stropping compound into the strop and place the blade on the strop the same way you sharpen BUT there is only one method for stropping. With the blade on the strop stroke away from the cutting edge as indicated by the green arrow. Do multiple passes on the strop alternating the side of the blade on each pass.

If you don't get it razor sharp the first time not to worry, it take practice because you are doing it free hand. You don't have a jig to keep
the angle of the blade consistantly, but once you get the hang of it you won't need one.

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