PDF for KN38 is here.
A dip and drip in Condursal before heat treatment.
After drying the protective Condursal looks like this.
Into the oven at around 860°C (1580°F) and climb to 1060°C (1945°F) for a short soak.
Out of the oven and cooling fast. This is actually almost an orange yellow when first pulled out...
And between the copper plates for a minute.
This is what the blade looks like right out of the plates. A quick check with a file to see that it hardened correctly and it's into the first tempering pronto.
I put the blade into the tempering oven along with the two others I hardened during this session.
For the grind I want a full flat with distal taper. Because this stock is thin to start with there isn't much to take off.
A few dozen light passes on the VSM ceramic 60 grit alternating between long ways and across the blade. Dunking in the water bucket every pass or two.
Getting the symmetry right. Check the primary bevels against the light as they are being ground.
Here we see the distal taper from the handle to the point.
Checking the edge with the caliper. 0.015" is good for a paring knife before cutting the secondary bevel.
I am trying some sandpaper that I haven't used before. It's 3M Pro Grade P180.
I hand sanded the blade a bit with long straight strokes and lubricated with water.
Some light contact with the conditioning belt, being careful not to burn the blade. Cooling in water as usual.
Running the conditioning belt at around 4500 Surface Feet per Minute.
The belt does a really good job.
Here I have tacked on my small stencil and will prepare the electrolytic etcher for putting my mark on the blade.
After applying a few milliliters of stainless steel electrolyte to the pad, I give it two 15 seconds applications on ETCH and one 10 second application on MARK.
After etching I squirt with windex and wipe with a clean rag. A very light buffing with a scratchless blue Scotch-brite pad evens out the mark.
Blade is taped up and ready to start working on the handle.
Next step is the handle work.