Chopping/technique threads?

[Nicholas]

I've already had a fairly successful day of chopping with my M43, but I'm pretty sure that my technique needs work. I also presume that this has been dealt with before, on this Forum. So, if there are any previous, archived threads on khuk-chopping and -slicing technique, could anyone redirect me to them?
Thanks.

 

[Andrew Colglazier]

I haven't done a chopping thread, but I do have a technique.

Generally speaking, I like to let the blade do the work rather than my muscles. What I mean by that is, I take more, lighter strokes rather than fewer, heavier strokes, and try to be as accurate in my chopping as possible.

This lessons fatigue, is more efficient IMO, and is safer as there is less chance of a strong blow getting away and doing damage.

I also try to position by body as low as possible to prevent blows from passing the target and continuing into a leg. IOW, I lower my center of gravity as much as possible in relation to the target to prevent over swings.

I also chop as much as possible with both hands rather than with just one hand. This gives me better control and there is less chance of the khuk getting away from me.

Hope this helps!

Andy

 

[iBlade]

I seem to remember seeing a how to thread on cutting and strokes etc on...ahem...another site...

 

[hollowdweller]

I haven't done a chopping thread, but I do have a technique.

Generally speaking, I like to let the blade do the work rather than my muscles. What I mean by that is, I take more, lighter strokes rather than fewer, heavier strokes, and try to be as accurate in my chopping as possible.

This lessons fatigue, is more efficient IMO, and is safer as there is less chance of a strong blow getting away and doing damage.

I also try to position by body as low as possible to prevent blows from passing the target and continuing into a leg. IOW, I lower my center of gravity as much as possible in relation to the target to prevent over swings.

I also chop as much as possible with both hands rather than with just one hand. This gives me better control and there is less chance of the khuk getting away from me.

Hope this helps!

Andy

A lot of what AC here says.


I'll add that I find it very difficult to chop straight down, meaning with the edge hitting the tree perpendicular.

The angle is different with every khuk, but you want to get a nice angle on the thing so you get a big bite of wood with every chop.

The biggest mistake IMO is trying to start on one side and chop clear thru anything.

You will end up with a smaller and smaller notch that is harder and harder to angle your blade enough to get a good bite with.

You want to chop in till you don't have any room then move to the other side of the log if it's something big and do the same thing. I normally stand over a log and chop on the opposite side of my body. Then once you have both sides chopped so it looks like an hourglass from the top start yourself a big notch on top and work down. Then once you don't have room anymore you'll have made yourself enough room to widen your bottom corners on both sides. Then it only takes a whack straight down or from the bottom up to make it fall.

If I am cutting something say 2" not big enough to go thru on one swipe but not serious chopping I'll whack one side, then change positions and whack the other side and usually the cuts will meet and you'll cut thru it.

When I am chopping campfire wood I'll take a long limb and put one end on the ground. Then holding it out from me I'll rotate the entire limb doing like 45 degree cuts all the way around. Then one good sideways blow will usually make it crack. I can really cut up a bunch of wood like that and you are not cutting back at your body.

 

[Nicholas]

A lot of what AC here says.


I'll add that I find it very difficult to chop straight down, meaning with the edge hitting the tree perpendicular.

The angle is different with every khuk, but you want to get a nice angle on the thing so you get a big bite of wood with every chop.

The usual recommendation see seems to be about 60 degrees. That much, I'd been fortunate enough to hear already.

The biggest mistake IMO is trying to start on one side and chop clear thru anything......If I am cutting something say 2" not big enough to go thru on one swipe but not serious chopping I'll whack one side, then change positions and whack the other side and usually the cuts will meet and you'll cut thru it.

AHA!!! That's where I was getting frustrated, especially when trying to do some test-cutting (with plastic bottles full of water): I was expecting to shear right through. By contrast, it "Chopped" fine through a 2" trunk (I took out a chinaberry in less than a minute.) Luckily, I didn't have to switch sides.

It may be that I'm simply setting my sights too high. The place where I've really had trouble is lighter vegetation (to say nothing of food in the kitchen), and a better sharpening job should help with that (I think). I was too conservative with it the first time.

When I am chopping campfire wood I'll take a long limb and put one end on the ground. Then holding it out from me I'll rotate the entire limb doing like 45 degree cuts all the way around. Then one good sideways blow will usually make it crack. I can really cut up a bunch of wood like that and you are not cutting back at your body.

Hmmm...interesting trick. It reminds me of one that I heard for splitting wood: saw halfway into it, and then break it on a rock (or something). Supposedly, it'll split by itself......after a few tries.......

 

[killa_concept]

AHA!!! That's where I was getting frustrated, especially when trying to do some test-cutting (with plastic bottles full of water): I was expecting to shear right through. By contrast, it "Chopped" fine through a 2" trunk (I took out a chinaberry in less than a minute.) Luckily, I didn't have to switch sides.

It may be that I'm simply setting my sights too high. The place where I've really had trouble is lighter vegetation (to say nothing of food in the kitchen), and a better sharpening job should help with that (I think). I was too conservative with it the first time.

Hey man! I would definitely suggest resharpening if you want the knives to take on lighter chores. I've recently acquired a 15" AK for a great price thanks to Aunty Yangdu's generosity. The edge looked fairly good for wood chopping, but had VERY tiny burs in some sections - this will be a lot more noticeable when it comes to lighter vegetation and kitchen work. I also have a slight bit of OCD when it comes to keeping my knives shaving sharp, so I instantly redid the edge when I got it. The karda also needed a slight bit of work by my overly high expectations. The whole process only took me about 15 minutes for both (v-edge on karda and slight convex on the AK) meaning the knives obviously came with already superb edges.

What I'm quite impressed by was that I was able to put a shaving edge on the kukri so easily, go outside and hack through 5" dia. cherry logs in about 2 minutes with ZERO blade deformation, wash off the blade, quickly strop it on a leather belt, and still be able to shave As I said before, this level of sharpness really shines with light vegetation and kitchen work - I was pretty much able to use the kukri as a scythe on some tall grasses and other weeds out back. It also allows for slicing through vegetables with just the weight of the blade (though the thickness of the spine causes some issues with "squishier" vegetables). I also wouldn't recommend using the kukri for kitchen work just because the acidity it's exposed to really does a number on the edge and polish (high carbon blades used in the kitchen really require maintenance)....

Anyways, I've said so much already for one post, so I'll cut myself off and post pictures. Sorry for the blurriness - but putting yourself in a position to test the blade's sharpness on your leg is a bit difficult when you intend on taking a picture as well:

 

[Nicholas]

I hear you about having three hands during photography; part of me has always wanted a cyborg eye with a camera implant.

But this is all starting to make sense to me now. The blade(s) came to me with a perfectly good chopping edge, and a tough one, besides (it's already taken a few minor dings with NO sign of damage). I figured it wasn't sharp enough yet, but clearly, I also overestimated how much I should be able to chop through in one blow.

And I'm not scared of the blade getting etched by kitchen work; my main kithcen knife has looked like that for years! And having gotten a good look at how durable Get's finish is on this knife, I think it'll take a while to get that way, anyhow. I'd be more worried about some light scratches it's picked up already, which I don't know how to buff out yet (hint, hint).

 

[Cpl Punishment]

A few points that have helped me:

1.) When I grip the kuk, I have my hand all the way back by the bell bottom. My index, middle finger, and thumb grip it securely, my ring and little finger loosely. When I chop I bring the kuk up high -- above shoulder level. Then if it's a thick piece of wood, I'll give maybe a 1/4 strength impulse, other wise just let the kuk drop and let the mass and gravity do the work. Just before impact, I snap the kuk with a sort of whiplash motion. You have to learn the proper timing for each kukri.
2.) Do not chop straight-in like you would an axe, use the whip motion, because that causes the blade to "run" as it chops in, basically cutting the wood fibers, rather than trying to cleave them.
3.) Generally, I find that an angle of attack of less than 45 degrees works best, and is different for each kukri. Example: the angle between the "trunk" and the blade is less than 45 degrees. For harder woods, the angle is usually closer to 45 degrees, for soft object, the angle is usually closer to 30 degrees. I say usually, because each kuk cuts differently.
4.) I find that they don't need to be able to shave to work very well, but the edge MUST be smooth. Little dings and dents really kill its performance.
5.) For the sweet spot of the curve, I like to sharpen the bevel all the way to the edge, and then slightly, convex the edge. This gives me the best performance on soft grass and edge retention on chopping wood.

ETA: the mass of the kukri really affects it's chopping ability, IMO. For instance, Hollowdweller mentions his not going through a 2" piece. He uses smaller kukris than I do. my 20" CAK will go through 2" of oak in a single, hard, swing. A lighter kukri won't. Don't expect miracles, they work on basic physics like anything else, they just have certain advantages due to geometry.

 

[Nicholas]

A few points that have helped me:

1.) When I grip the kuk, I have my hand all the way back by the bell bottom. My index, middle finger, and thumb grip it securely, my ring and little finger loosely. When I chop I bring the kuk up high -- above shoulder level. Then if it's a thick piece of wood, I'll give maybe a 1/4 strength impulse, other wise just let the kuk drop and let the mass and gravity do the work. Just before impact, I snap the kuk with a sort of whiplash motion. You have to learn the proper timing for each kukri.

So it seems; my first chopping session made my wrists a bit sore. Obviously I haven't found it yet. But I was wondering of the motion of a whip (or, for more civilized folk, the casting of a fly-fishing line) was a good analogy for this technique. Now I know. (And knowing is half the battle!)

2.) Do not chop straight-in like you would an axe, use the whip motion, because that causes the blade to "run" as it chops in, basically cutting the wood fibers, rather than trying to cleave them.

I saw this happen with the chinaberry: I got through it all right, but it did tend to shred.

3.) Generally, I find that an angle of attack of less than 45 degrees works best, and is different for each kukri. Example: the angle between the "trunk" and the blade is less than 45 degrees. For harder woods, the angle is usually closer to 45 degrees, for soft object, the angle is usually closer to 30 degrees. I say usually, because each kuk cuts differently.

Of course. Are we measuring these angles from parallel, or from perpendicular?

4.) I find that they don't need to be able to shave to work very well, but the edge MUST be smooth. Little dings and dents really kill its performance.

That hasn't been a problem; this edge seems quite tough. Nevertheless, I'm using the chakmak very diligently.

5.) For the sweet spot of the curve, I like to sharpen the bevel all the way to the edge, and then slightly, convex the edge. This gives me the best performance on soft grass and edge retention on chopping wood.

That was the problem: I only had it sharpened AT the edge, at the time. That "little bevel" was my undoing.

ETA: the mass of the kukri really affects it's chopping ability, IMO. For instance, Hollowdweller mentions his not going through a 2" piece. He uses smaller kukris than I do. my 20" CAK will go through 2" of oak in a single, hard, swing. A lighter kukri won't. Don't expect miracles, they work on basic physics like anything else, they just have certain advantages due to geometry.

Well, I'm at 18.625" with "Rufus," so there's some potential there.

 

[killa_concept]

4.) I find that they don't need to be able to shave to work very well, but the edge MUST be smooth. Little dings and dents really kill its performance.
5.) For the sweet spot of the curve, I like to sharpen the bevel all the way to the edge, and then slightly, convex the edge. This gives me the best performance on soft grass and edge retention on chopping wood.

While this is definitely true for chopping, I find that a well sharpened (shaving) edge really shines when it comes to light vegetation and kitchen work. I haven't had my 15" AK dull (less than shaving sharp) enough to verify this, but it's held true for all other knives I've owned.

I definitely agree with your statement on the method of sharpening... you only want very small portion of the edge convexed - a full convex right up to the primary bevel would probably end up being too acute to maintain a good edge after heavy chopping.

ETA: the mass of the kukri really affects it's chopping ability, IMO. For instance, Hollowdweller mentions his not going through a 2" piece. He uses smaller kukris than I do. my 20" CAK will go through 2" of oak in a single, hard, swing. A lighter kukri won't. Don't expect miracles, they work on basic physics like anything else, they just have certain advantages due to geometry.

Yep - technique and blade sharpness only gets you so far... the knife is always going to be limited by how much mass it has behind it. My 15" AK is a bit short, but I find it does what I need it to do. I'll definitely be looking to get a 20" in the future though

 

[Cpl Punishment]

I haven't had a problem cutting light grass with mine being less than shaving sharp. I also have better edge retention than when I did the shaving edge. Do whatever makes ya happy, though, we're here for the fun, right?

 

[knifes101]

I have a related question. When sharpening the blade, what should the final angle on the edge of the blade be for a kuk?

 

[Dave Rishar]

I made a video about this some time back. Unfortunately it's not where I thought it would be and, honestly, it sucked anyway. I may do another one.

Basically you want to chop a "V" into the work. Some people spend a while on one side and then shift to the other, some switch back and forth continuously. Some people hit hard, some people hit soft, and some people (HD ) "nibble." There are many ways. The short of it, expressed some years back by a man much wiser than myself, is not to let your body get in the way of the cut. That has multiple meanings.

Expect soreness and blisters if you're not used to something like this. The body must adapt obviously. However, if you've been doing it for a while and you're still having problems then your technique should be looked at. My approach to this is to shift as much of the load as possible to the muscles best adapted to it: the legs and the back. "Sink" your balance on downward cuts, rise on upward cuts, and keep your back involved as much as you can. Your arms will tire far more easily than either your legs or your back, so give them the lion's share of the load.

 

[hollowdweller]

ETA: the mass of the kukri really affects it's chopping ability, IMO. For instance, Hollowdweller mentions his not going through a 2" piece. He uses smaller kukris than I do. my 20" CAK will go through 2" of oak in a single, hard, swing. A lighter kukri won't. Don't expect miracles, they work on basic physics like anything else, they just have certain advantages due to geometry.

Exactly.

Although I have some heavy khuks I don't like anything over 25 oz.

Actually the 17" 23 oz is my perfect khuk. But I have a 15" 25 that I like real well too.

Although chopping big stuff is fun my main use for khuks is keeping the trails clear in my woods. That means I'm mainly cutting stuff from small limbs to stuff around 6"

Anything over 25oz and I find it hard to swing it fast enough to cut small stuff. Well let me rephrase that. IF I swing it hard enough to cut small stuff I have a hard time stopping the blade and it puts a SERIOUS hurt on my shoulder.

Also some khuks are just impossible to machete with without major work. My first khuk was an 18" ak 2 lbs. It chopped big stuff great but due to the super fat edge I ended up beating the smaller limbs off because with that fat convex edge unless I had the angle perfect the blade wouldn't bite. Straight on and it would break them off. Too angled and it would glance.

That's when I started only getting the Bura stuff cause his edges are thinner. Sgt K's are pretty good too.

So when I'm cutting stuff up I usually like to start with all the smaller limbs and then cut and stack the crown:

Some of these pics are not of the same tree but here goes:

Starting the cut down one side

Broadening it to both sides

Notch is getting too narrow

So I come from underneath and knock the narrow corners out of the notch

Done (17" 23 oz Ganga Ram)

 

[Nicholas]

I haven't had a problem cutting light grass with mine being less than shaving sharp. I also have better edge retention than when I did the shaving edge. Do whatever makes ya happy, though, we're here for the fun, right?

Of course, that brings me back to my long-ago point (made all the way back in my first post!) about Khukuri edges being sharpened differently at different spots along the blade: maybe the "sweet spot" doesn't need to be as sharp as the tip.

 

[killa_concept]

I haven't had a problem cutting light grass with mine being less than shaving sharp. I also have better edge retention than when I did the shaving edge. Do whatever makes ya happy, though, we're here for the fun, right?

Completely agreed - different people, different techniques and what works best for one person might not work as well for another. I'm in no way trying to question that, mind you!

However, your statement throws me off: given the same edge angle, a shaving sharp edge can't have worse edge retention than one which is not. A blade is "shaving sharp" when the edge has become highly polished. Shaving sharp = Higher polish = less drag through the material you're cutting = less chance of blade damage = better edge retention. Simple physics says that your shaving edge should have held up better unless you used a more acute angle to create a shaving edge

I have a related question. When sharpening the blade, what should the final angle on the edge of the blade be for a kuk?

21 degrees would be my suggestion if you're going to do a V-edge. However, most kukri (and heavy use knives in general) users - myself included - would suggest a convex edge. With a convex edge, it's difficult to approximate the exact angle... I would say figure out what 18 degrees is on a flat surface, then use that angle on a mousepad/sandpaper setup. The bend in the mousepad should give you a nice convex edge that will hold up to a lot of chopping

Just make sure to maintain the primary bevel every now and then or you'll find the thickening of the edge screwing you up:

 

[hollowdweller]

starting at the top

Hourglass shape cut

17" 23 oz Foxy Folly

Starting to section the tree

This particular section was harder cause it was on the ground almost. Notice I had to make the notch wider to compensate

Getting more sections cut up

Showing how I widened out the bottom.

Done. I worked on this one several evenings. The last day is the one when it snowed.

 

[hollowdweller]

I tend to take my time and place my blows. If you are cutting up something that is going to take a long time you want every chop to count. Sometimes I'll just stop and size the thing up, letting my arm rest and trying to figure out where to strike next that will remove the most wood with the least effort.

Here's a pic that sort of shows how much I tend to get with each chop. Cause I don't put a lot of force behind it not as much as some.

Also a little khuk can do a lot. This pine was around 7 to 8" and the 15" 20oz ganga did fine with it.

 

[Cpl Punishment]

However, your statement throws me off: given the same edge angle, a shaving sharp edge can't have worse edge retention than one which is not. A blade is "shaving sharp" when the edge has become highly polished. Shaving sharp = Higher polish = less drag through the material you're cutting = less chance of blade damage = better edge retention. Simple physics says that your shaving edge should have held up better unless you used a more acute angle to create a shaving edge

My shaving edge was, indeed, thinner.

 

[Nicholas]

Well, that explains it, then. I'm going to tend to this today, and I'll let you know how it works....