Advice on Project Khukri

[drbarnes]

extending the tang with jbweld & aluminum will likely weaken it rather than improving it.

I am really confused by this, not sure how making the tang longer is gonna weaken it!?

Anywhooo...

I got the piece of 1/4" aluminum from a local industrial supply store

I traced the tang on with pencil, which worked ok, but got erased by WD40.

Then I used the original handle as a template because I really liked the shape.

I went to the garage and clamped it in, original plan was to use a dremel and cutting disk - didnt work well. Next plan was a sawzall which worked awesome because it saws...all It was easy and alot faster to cut with the sawzall. It shouldve been my first choice - I thought it would be hard to control and would be a rough cut but it was easy to control and left a great cut. I used WD40 to lubricate which is like an eraser for pencil and sharpie. Maybe a crayon would work?? Or lay it out with tape?

This was the initial rough cut

I came in and checked with the khukri- I made the cut for the tang a little big. my plan here is to use some aluminum as a "shim" when I JB weld it on or make start over and retry a second time. I have 3' of the aluminum.

I sketched a more precise handle shape I am going for.

I cut it more to the shape I was wanting and cleaned it up a little bit with 40grit sand paper and a metal file. The sandpaper doesnt work too fast, and the old metal file I had seems worn out.

At this point I am leaning towards redoing the handle for a second time. After having a bit more experience with cutting the aluminum I feel confident that I can make a better handle cut the second time, especially if I have better lines to follow, and a decent metal file.

Any input/comments/criticisms are appreciated. This is a learning experience for me. Lots of trial and error ... mostly error

thanks for looking! David

 

[bladeright]

I am really confused by this, not sure how making the tang longer is gonna weaken it!?

Anywhooo...

I got the piece of 1/4" aluminum from a local industrial supply store



At this point I am leaning towards redoing the handle for a second time. After having a bit more experience with cutting the aluminum I feel confident that I can make a better handle cut the second time, especially if I have better lines to follow, and a decent metal file.

Any input/comments/criticisms are appreciated. This is a learning experience for me. Lots of trial and error ... mostly error

thanks for looking! David

why dont you get a piece of flat steel plate and make the shape you want then weld that to the tang. the weld shouldnt hurt the heat treat of the blade and it should hold indefinitely. just go slow and cool off and check you work lots during this procedure. i could oxy ace or mig it in a few minutes.

ive never used jb weld much, but for chopping i wouldnt trust the bi-metal configuration.

 

[drbarnes]

why dont you get a piece of flat steel plate and make the shape you want then weld that to the tang. the weld shouldnt hurt the heat treat of the blade and it should hold indefinitely. just go slow and cool off and check you work lots during this procedure. i could oxy ace or mig it in a few minutes.

ive never used jb weld much, but for chopping i wouldnt trust the bi-metal configuration.

I thought about steel but went with aluminum because of the weight, I didnt want to throw off the balance that much. I think the JB weld sandwiched inbetween the horse stall mat will be strong enough but am taking the steel idea into serious consideration because that is a comment I get most often when I talk to people.

 

[Karda]

I am really confused by this, not sure how making the tang longer is gonna weaken it!?

Anywhooo...

JB Weld is likely not going to hold up under the stresses of chopping when used to hold two pieces of metal together like this.
An actual weld would be better, but even then it could be a weak spot unless expertly done.

 

[leebrewer]

Try using a grease pencil/china marker on the aluminum. Aunt Yangdu sold weekend project khukri blanks a few years ago. I remember guys posting their handle mods (step by step). You might get some ideas from the archives if you want. I see where your going with the aluminum now. Lookin good.
With my Hanuman, I choppped, split, batoned oak the same as I have with my CAK. As long as I had about an inch of blade on each end, longer than the wood, I did it and never had a hint that it wasnt peened on the end or chiruwa. As long as you got a pin in there and a good grip to hold on to, it should be killer.
I still wanna see what you do with your Lord Hanuman head also.

I've seen em remove that bolster and take their handle past that point also. Extend the tang thataway. That bolster could be where the top of your hand is.

 

[drbarnes]

Well, its been a while but I wanted to update the thread with the finished product.

I used GFlex epoxy to attach my aluminum tang extender to the stick tang because I was afraid of JB weld being too brittle. The GFlex is supposed to have some give and still have a very strong bond. It feels very solid.

For the handle material I got some 1/2" neoprene from Grainger - I went with some softer stuff Durometer 50 Shore A. It was easy enough to cut with a utility knife

I used a dremel tool with a high speed cutter to bore out the handle shape.

It worked extremely well!

Next I used the same GFlex to put the neoprene on the handle, I put it in the vice and left it over night.

I went used a belt sander to shape the handle, I still have more work to do, but it is in useable condition right now so I couldnt resist!

The handle looks big, but it is very comfortable and with the soft neoprene handle, and it chops like a beast! I didnt have much time tonight but I took a piece of firewood today and did a little chop comparison between my custom David Wesner chopper which is awesome, my benchmade 171 chopper and this AK. 25 chops for all.

 

[JayGoliath]

Good work but just wondering if you are going to put in a pin on to the front hole?

 

[drbarnes]

Good work but just wondering if you are going to put in a pin on to the front hole?

Right now I am not planning on putting a pin in the front hole.

 

[davidf99]

Right now I am not planning on putting a pin in the front hole.

So far, so good, but as a basic safety precaution I suggest that you reconsider and put a pin in the front hole.

The handle is made of three different materials: the steel tang, aluminum extension, and neoprene sheathing. These materials react differently to the stress of hard contact, they expand and contract differently with changes in temperature, and they flex in different ways. LIkewise for the epoxy.

The neoprene might be too soft to hold everything together, and repeated flexing could loosen the bond between the neoprene and the metals. There is a substantial gap between the steel tang and the aluminum piece, and they are epoxied along a narrow edge. If the epoxy fails along that edge, perhaps after the hundredth swing, the blade could go flying out of the handle in an unpredictable direction.

It might never happen. However, a pin through the front hole could prevent a worst case scenario. You'd know it if the epoxy failed, but at least the blade would not become a steel missile.

If you do have a problem down the road, I think the same design would be much stronger if you replaced the neoprene with hardwood slabs and attach them with a combination of epoxy and pins. That would make the total handle much more rigid and less likely to fail. It would be chiruwa style with the aluminum extension showing between the wood slabs.

-- Dave

 

[DevilMan]

Nicely done... I don't know about a pin through the front existing hole and since it's hard to find it may be a bear to do, but I think putting a hollow dowel through and then flaring each side would work well. Just run a countersink on each side then push a hollow tube through and flare it out.

Either way... nice work.

DM

 

[drbarnes]

David you bring up some good points, I will make the front pin as the next part of the project, and locatig the hole should be easy, I can feel where it is through the soft neoprene, amazing how tough this stuff is! My dog started chewing on a piece of scrap and weve been playing tug of war with it and its held up better than the toys we buy her from the store.

I have a 3/8" hollow pin for the rear lanyard hole but the front hole is a bit larger. Do you think I should use the same dowel or get a larger solid pin, or even a solid wooden dowel?

 

[leebrewer]

Does the neoprene fill up the bolster? A pin may dig into your hand as the soft neoprene compresses around it in your grip?