How I Made A Through-tang Kitchen Knife

In the spirit of the season and sharing, I thought I would do a walk through on how I made my last stock removal through-tang kitchen knife. This will probably be in several parts and be a little heavy on photos. Any comments, ideas, suggestions or criticisms are welcome!


The style is a kiritsuke-gyuto-sujihiki mix, but I will call it a kitchen utility with a 9" blade. The steel selected is Böhler-Uddeholm's AEB-L stainless steel. The stock is 0.094"(3/32") x 1.5" x 12" long. At $1.18 per inch this is very reasonably priced for some great steel that sharpens up very well.

The pattern is from a KN18 (http://dcknives.com/public/downloads/KN18 Template - DanCom-2015.pdf).
The original pattern was printed and glued to some thin plywood.
You can see this is for a full tang version.


Taking the full tang and converting to a through tang means getting more blade from the same piece of steel. With my most valuable of weapons, the Sharpie, I ad-hoc drew the new shape and estimated the tang.


On the Porta-Band I cut the shape out, staying close to the line, but leaving some room for grinding any wobbles out.


On the belt grinder I use a work rest at 90° to the belt and make bring the shape down to the lines.
I take the liberty to "tweak" the shape here. I lengthened the clip to give it more of a sleek shape and allow for two fingers to sit there.


In the tang, I drilled a hole and cut with the bandsaw to make a keyhole.
I then shaped an 8-32 x 2" stainless steel machine screw to fit into the keyhole.
This will extend through to the butt when finished. This is the first time to do this, so I am hoping it works.


As I am going to grind the bevels after heat treat, I am going to check for straightness, clean with acetone coat with Condursal. I give it two coats with a brush and let it dry.


I take the oven up to 1060°C (1940°F) and hold for a brief soak.


Normally, I plate/air quench AEB-L, but recent experiments indicate (empirically anyway) that it gets
harder when oil quenched. As soon as it goes black I take it out of the oil. The tempering oven is
standing by hovering around 180°C (350°F). The blade goes in for 2 hours, cools to room temperature and back up to 180C for two more hours.


... to be continued.

 

After the hardening and tempering, I start grinding away the primary bevel.


I tend to alternate between longways and shortways. I want a gradual taper to the point and a slightly convex grind from the spine to about 0.5mm (.02") at the future cutting edge.



After the bevel is close, I give it some finish with a conditioning belt.


Now the fun part of getting the handle together. The components of the handle are:
1/8" AEB-L stainless, African Blackwood, red vulcanized fibre spacer, Amboyna burl block and some 304 stainless.

The first piece has to fit the tang-shoulder junction very well. I drilled a series of holes in a row and then make a slot with needle files. Then with tiny adjustments with the file I slide the piece on the tang and test it. Repeat until the fit is as best as you can get it. This is a photo taken when I was doing the fitting. After it's fitted, it gets sanded and buffed.


The Amboyna block is cut closer to the final size, but still thicker than needed.



The block is then drilled out to accept the tang. I drilled two holes, then bridged them together by rocking the block with the bit inside.
The other end of the block has a 3/16" hole, on centre, that meets the slot somewhere about mid block.


The butt cap is a piece of 3/8" 304 stainless steel that has been drilled (9/32") and tapped to 8-32 with a bottoming tap. Hopefully this will thread on to my special screw that will attached to the tang.


I've also cut some African Blackwood and few pieces of red fibre spacer.
Here it a dry fit to see how everything lines up and squeezes.


Here is a shot of all the handle components in an exploded view.


Mixed up about 10ml of West System's G/flex and slathered it on and filled the slot.


The screwing on of the butt cap squeezes everything together. This causes the epoxy to ooze out everywhere, but that's the idea.


After a good day in a warm place, I started squaring up the handle. A 36 grit Zirc belt on the flat platen makes easy work of this task


I am sure to use plenty of dunks in the water to cool the steel when grinding.
It gets very hot and will burn the epoxy. I literally dunk every pass on the belt.

Here the faces are square and I slanted the butt cap.


Now I can start rounding and adding some shape to the handle.
I like the work rest for this as I generally work at 45° angles to start the rounding.
Again, lots of dunking to keep the stainless cool.


After the handle is more or less the desired shape, checking in the hand and tweaking it, I put a lightweight AO belt on and work the shape in slack belt mode.
Running this belt fast will burn the wood. In a controlled burn I bring out the darker parts of the burl.


I have applied some tung oil to the handle and buffed.


To be continued...

 

A few last details to work on. The maker's mark is electro-etched on the blade.
I add my logo as well as the steel type on the opposite side.


To set the edge I use a 220 grit belt to get a wire edge, then water stoned to get a very sharp cutting edge.


A little spit polish here and there and we're done.
I hope that you have enjoyed this. Your comments and questions are always appreciated

Dan

 

Awesome. I'm really interested in trying this out. Great tutorial! Did you tack the machine screw in place? Also, did you get any warping when you quenched? I've seen Aeb-l plate quenched, and only read of it oil quenched.

 

Thanks Chris,

I had hoped that the shape of the screw head (modified) to sort of grip when tightened. I was prepared to put some super glue on it at construction time, but it held tight. It's also kind of pressed into the keyhole with pliers.

The AEB-L was heat treated before any bevel grinding, so I had the whole 3/32" thick stock. The tang was a little off, but I go that fixed immediately after the steel was black.

Dan

 

That's good to hear. I may have just spent some money at CKS lol. 25" 3/32" aeb-l, 12" 3/32" 1095 and 16" 1095 x 5/32". I also just ordered some curly koa. I think I found a diamond in the rough actually, 4 pcs of 1.5"X1.5"x4.5"-7" for 70$ shipped. It looks really nice anyways. Here's to hoping eBay doesn't pull the wool over my eyes. But he did have 100% rating. I haven't tried kitchen knives before, but really wanted too. This tutorial should go well for me I hope. I'll be sure to show off my results. Hopefully in the new year

 

How hard on the belts was it to grind post-heat treatment?

 

A little hard on belts, especially the right angles. Initially, I use an old belt to knock the sharp edges off. Then a fresher belt to cut the bevels. Ceramics hold up pretty well against hardened steel.

Dan

 

Great looking knife Dan. Thanks for another step by step.

 

Awsome knife! Thanks for all the pics, it's great to see how it's done.

 

Thanks! There are many ways to do it. This way made sense to me, but someone out there will always have improved methods. That's the beauty of sharing knowledge. ;-)

Dan

 

That looks great Dan!