After the blades are shaped to the correct profile on the belt sander the
holes for the pivot and thumb stud are drilled. The hole for the head of the screw for
the thumb stud is usually countersunk.
Even though I get the basic shape and hole placement of the blade from a pattern
it is important to remember that these blades are handmade. The blade is
shaped using an ink line as a guide and the holes are drilled on inky little dots.
The placement of the holes within the shape of the rear of the blade have to
have certain geometric relationships if the folder is to function properly.
To help me be sure I achieve that relationship I use a little wooden jig with a couple of
metal rods stuck in it. These rods approximate the relationship of the pivot
and the blade stop as they will be in the finished knife.
The back and bottom rear of the blade are ground until the blade fits into the jig about right(3).
Final fitting will take place when the handle and blade are matched. After the blade works in the jig, I set the angle of my grinder's platen 10 degrees off from verticle (4A).
Then, I mill the angled locking ramp in the rear of the blade(4B).
In picture (5) you'll see that a center line has been drawn on the edge of the blade. The object of the game
is to grind the sides of the blade down evenly so that the cutting edge falls on that line. At this point, I
usually file the thumb grooves into the back of the blade (6) because it's a little easier to get the blade to
stay put in a vice while it's still flat. Notice that the file I'm using is about a half inch wide. It's a
special file called a checkering file and cuts about 10 grooves at a time. This makes it a lot easier
to keep the grooves even.
In picture (7) you can see me holding the blade against the grinding belt to grind
the bevel to the centerline. Yeah, I know what your thinking - that nobody could
possibly do it that way and keep the lines straight. That's what I thought too
and some days I still think so. But, with practice it can be done and just about
every stock removal knife maker does it that way.