The finished knife first!
I started with a blank of 5/64" x 2" x 18" piece of O1 tool steel. I've made a number of these k-tip gyuto/bunkas in the past and really like the 150mm size, but wanted to go more towards the 175mm range with this project because it's likely more versatile and frankly a little more impressive!
I printed and traced out an image onto the steel. I had enough for 2 knives in this piece of steel.
I rough cut out the blank with a band saw, hand saw, and angle grinder with a fiberglass cutoff wheel.
Edges cleaned up on the sander.
Laid in the rounding on the choil.
Pics are kind of out of order but I started laying the bevels in at 2.5 degrees. I realized the angle was too steep and changed it to more like 1 degree.
Just a pic of my bevel jig.
After a moderate amount of grinding, I covered the blade with refractory cement. This pattern encourages the development of a differentially heated blade and can produce a hamon, though I'm told with O1 that's basically impossible. I don't buy it though because I've definitely gotten hamon development in the past and I like it to pre=otect the blade during the heat-treat phase.
My heat-treat setup with MAP gas.
The magnet is to tells when the blade is ready for the quench.
This is not super reliable or great but I've had good luck doing it this way. Building a proper heat-treat oven is on my list of things to build!
Couldn't get pics of the quench, but I use just regular vegetable oil. Had to scrape the cement off the blade before clamping.
Clamped in the vise between two pieces of flat stock to discourage warping.
Red and white spacing material (just cardboard that's impregnated with a resin) ebony, bloodwood, and a white acrylic material. I wanted to incorporate the stainless spacer I made from another failed project, but I didn't. Grinding metal tends to destroy the epoxy bond so I need to use skinnier material in the future.
Regardless, I skipped the stainless!
Everything rough cut out.
Working on thinning the bevels.
Thought it was thin. It was not.
Tried doing a flat sanding. I don't have the patience for hand work.
Since the tang ended up being offset (because I was too aggressive with the file in the beginning) I had to test fit everything off-center.
This pic has nothing to do with that, but I noticed that I didn't mention it.
Regardless, I wanted to build the but end as stable as possible, so I aligned the layers to a dowel that I fit to the rest of the handle.
Just some alignment pics.
To align the tang to the bolster, I like to drill 3 holes and then file out the shape of the tang to match. That way you get a tight fit and finish on the outward facing face of the handle.
To align everything and to get it all glued up, I like to drill through *nearly* all the way through the back side of the bolster piece, to allow the tang and the dowel spacers room to but into the bolster.
Hand file work for fitting the tang.
Little shot of the fit. Very tight, if I do say myself.
So this is to show the construction technique. You drill a uniform hole through every handle element that fits a wooden dowel. You then slot the dowel to fit the knife tang. All that fits through the handle material to make the handle.
Final fit test and everything cleaned and broken down, ready for epoxy.
Glued up, clamped up, blade taped up.
Dried and ready for shaping.
Oh wait! Fuck you! Broken belt! No grinding for you! Gotta wait on a replacement part!
I clamp my angle grinder in teh vise as a modified buffing/sanding wheel. Works pretty well!
At this point, I really wante to test the grind. So I wanted to put an edge on it and cut some food.
I have a angle guide sharpener I got
on amazon that I really like. I cannot hit hand sharpened angles nearly as well as this thing does. I know it's a crutch but I don't care. It gets a reliable edge very quickly.
I was really happy with the design of the knife after doing some test cutting. It was still FAR too thick behind the edge, so I needed to do some thinning. I tried to get a rig going to flatten the bevels by hand but I don't have the patience for that. I ended up just doing it on the sander.
Layout fluid helps with bevels but I ended up taking it all the way to the spine.
Flat grind. Looking much thinner.
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