Purpose of recurve?

Its to "catch the cut".

One pf my favourite folders, a Blackjack Mamba has it, and its an excellent knife.
I found less useful on medium fixed blades.
Can work on really big knives to focus the shop and catch springy stuff.

Those who can't freehand sharpen bitch about them. Its not difficult.
 
Similar to others, I was always told that the reason for a recurve, was to change the angle of the material to the edge, especially leading up to the "curve back" to the normal edge. So on things like a Machete type object, that curve lets the material (grass most likely here) slide down the edge, and then get "forced" into the recurve portion of the blade, making sure it gets cut before it slides all the way off the tip of the machete.

Think about it kind of like you're on a roller coaster. You have relatively low contact with the track (edge), as you go down, but as you hit the bottom of the drop, and curve back up, you're forced hard into your seat (the edge again) as you start to go uphill. This is what is helping those types of cuts.

And, I've never thought about it like this, but I guess a canted blade angle is effectively a recurve. I just haven't ever described them as such.

And personally, I'm not really drawn to recurves, particularly on smaller blades. On larger blades, I so far have not desired to seek them out, but if a blade I like has them, I'm not opposed to it. Maybe that will change over time, as I continue to move around, and find new uses for tools, etc.
 
The draw cut is what I always found nice about a recurve, though I eventually ended up with a karambit/claw type knife as an extreme. Worked well for netting, cardboard, and similar things that don't have a backing, as some have mentioned. The karambit, for how I used it, was like a recurve but the recurve was at the tip instead of somewhere in the belly which made it a lot more accessible. It also made it dull faster since a lot of cutting happened in that tip area where the more aggressive curve started.

I also find it looks pretty nice but that's just a bonus when picking a knife that's functional.
 
For me a recurve works magic on breaking down cardboard. Material is drawn into the recurve essentially accelerating the cut. I don't have many anymore but I found them no more difficult to keep sharp with a cheap ceramic rod than any of my other knives.
 
Great thread.
I really like the recurve on the Emerson Commander and my Willumsen Tuco.
rolf
 
FortyTwoBlades said:
A lot of them on modern designs are just eye candy rather than serving an intentional practical use. However, recurves and cants are functionally employed to manipulate the edge presentation to the target for a given hand/arm position. They'll usually do a good job of snaring or catching hard, flexible targets that want to slip off an edge, and can also aid in tasks like pushing cuts delivered with the heel of the blade, depending on how the particular design is done.
Click to expand...

This^^^

Bottom line ... for the most part, eye candy.
 
craytab said:
For me a recurve works magic on breaking down cardboard. Material is drawn into the recurve essentially accelerating the cut. I don't have many anymore but I found them no more difficult to keep sharp with a cheap ceramic rod than any of my other knives.
Click to expand...


I've wondered about recurves too. Never could see the need for them though craytab suggest its worth a rethought. I have a few really curved blades but for a slight recurve in the cutting edge that feature has just seemed to be something that would be more troublesome than beneficial. Ceramic rods would be an easy sharpening solution - a PIA on a flat stone. Now I may need to buy another knife :rolleyes: :cool:
 
Also, on choppers a recurve can be a side affect of a forward mass distribution to the blade.

Bottom line is that recurves should be used judiciously by designers to contribute to the functional performance of a design rather than detract from it. If the intended context of use for a design means it would benefit from a recurve, go ahead and put one on it! But if it doesn't...don't. Please.
 
as said, to me:

- It helps add chopping power and forward weight, making this 6" knife chop like a straight 8 inch blades I have, and the angle the hand makes on impact makes it really non-tiring and gives much less stress to the joints

CAM02934_zpsg4in3gpf.jpg


- Recurve grabs twigs, standing plants, roots, grass and herbs I have to cut with fast swings, drawing and catching them into the sharp edge
- Allows to scrape/peel wooden stakes, trunks and logs with the inner portion of the blade

CAM02748_zpsth4irtla.jpg


- Works very well to split large fruits and veggies (coconut, watermelon, guayaba, mango, pumpkin, acorn squash) by doing a little vertical chop and then pushing down and forward, following the curvature of the knife

CAM04103_zps8ijgp0fh.jpg
 
craytab said:
For me a recurve works magic on breaking down cardboard. Material is drawn into the recurve essentially accelerating the cut. I don't have many anymore but I found them no more difficult to keep sharp with a cheap ceramic rod than any of my other knives.
Click to expand...

My understanding is that a recurved blade is best for game processing, so it is typically used on Hunting knives. This makes perfect sense to me, since, as Craytab pointed out, material is drawn into the recurve. I would image cutting through sinews and thick hide would be easiest with a recurve instead of a flat knife that the material could slip off easier when you can't see the blade under the hide. If you take a look at Buck's hunting section, you will see that a good portion of the knives there have recurves, particularly the ones with names containing the word 'Skinner' (i.e.: https://www.buckknives.com/product/paklite-skinner-knife/0140FAM01/ )
 
Lots of good answers so far. I've had a fair amount of experience with kukri-type machetes, recurve knives like the Clash and Blur, and concave shapes like hawkbills and karambits.

In my experience, you get more cutting edge and more choices of contour for how you cut. The concave portion does "catch the cut" so to speak. For instance, instead of slipping off a convex edge, things tend to pull into a concave edge. This effect is more pronounced and easier to take advantage of with fully concave shapes. If you've spent lots of time cutting rope, twine, etc. with one of those blades, you know what I'm talking about. (That effect can also help squeeze more use out of a blade as the edge wears down and I've wondered if that promoted its historical use with softer steels.)
 
Mama says that recurve blades are magic rays of sunshine that come down when you're feeling blue.

Straight edged blades are tools of the devil...
 
shortwinger said:
Mama says that recurve blades are magic rays of sunshine that come down when you're feeling blue.

Straight edged blades are tools of the devil...
Click to expand...
Let us know when the devil has a sale on some of those knives.
That would be soooo cool!
 



SD / emergency survival folders for fast cutting .
 
Last edited:
You must log in or register to reply here.
Back
Top