How do you guys grind your knives with slight recurves?

T

Tyler.t76

Joined
May 19, 2022
Messages
70
I wanted to give a small recurved knife a go and I’m wondering how you guys do your bevels on them? I’ll post a picture below I’m wondering if such a slight recurve would even be much different than grinding my usual bevels. I’m using a 2x72 with flat platen but I do have a 12” serrated contact wheel if anyone thinks that’s a better option.
https://imgur.com/a/MeUMZAd
 
Depending on the amount of recurve usually I end up grinding using about 1/3 of the platen, so if I’m grinding the right side of the blade holding in my right hand edge up I’ll use the right third of the platen.
 
Richard338 said:
Easiest on a flat platen. The more extreme the curve, the more you will be working on one edge of the platen. I did this kris dagger a few years back and it was a roller coaster.
View attachment 2042028
Click to expand...


Jeasus.


Thinking about grinding that is causing me anxiety
 
I did my first one recently, just to make it extra interesting I used my 72" radius platen. One side turned out really well the other was just ok. It was a knife for one of my daughters, a design I was playing around with that she really liked. It's in MagnaCut at 62 HRC.

It was an interesting experience doing it, using the edge of the platen for part of it and following the grind curve for the rest.
 
How to grind a slight recurve. The Nathan the Machinist way:

Step 1: Make a knife with a long straight section on it.

Step 2: Develop the dreaded 2-inch grinder divot in the straight area.

Step 3: Grind out the dreaded 2-inch grinder divot, keeping the lines even on both sides.


(Repeat step 2 and step 3 several times as needed)

TADA! You did it! You now have a slight recurve on your knife and additional stimulation for your developing substance abuse problems!

Step 4: (advanced) Quit your day job so you can do this everyday!
 
Nathan the Machinist said:
How to grind a slight recurve. The Nathan the Machinist way:

Step 1: Make a knife with a long straight section on it.

Step 2: Develop the dreaded 2-inch grinder divot in the straight area.

Step 3: Grind out the dreaded 2-inch grinder divot, keeping the lines even on both sides.


(Repeat step 2 and step 3 several times as needed)

TADA! You did it! You now have a slight recurve on your knife and additional stimulation for your developing substance abuse problems!

Step 4: (advanced) Quit your day job so you can do this everyday!
Click to expand...
looks suspiciously like the notes I have for my upcoming autobiography
 
Another Shepherd said:
Hawkbills are useful, but what is the practical purpose of a slight recurve? To me, it's just a nuisance to sharpen.
Click to expand...
It pulls into a cut and technically gives you a longer cutting edge. That said on small knives the difference between a slight recurve and a straight edge is minimal outside of overall aesthetic. They really aren’t hard to sharpen I can use a normal flat stone to sharpen even a full recurve like on a khukuri or karambit you just end up using the edge of the stone more.
 
Joshua Fisher said:
It pulls into a cut and technically gives you a longer cutting edge. That said on small knives the difference between a slight recurve and a straight edge is minimal outside of overall aesthetic. They really aren’t hard to sharpen I can use a normal flat stone to sharpen even a full recurve like on a khukuri or karambit you just end up using the edge of the stone more.
Click to expand...
True, not hard to sharpen, just takes longer than a straight edge.

I have a Woodman's pal with a slight recurve. It cuts fine, but I can't tell that it cuts any better than my other machetes. But I'm thinking about getting something with more of a recurve, such as a brush hook or bank blade, which came up in another thread.
 
I make slipjoints and have started incorporating more of the recurve blade into my patterns because it is something different...i also grind my bevels on the outside 1/3 or 1/4 of my wheel, depending on how much room i have
 
Manyb things help - Large wheel, radiused platen, 1" wide contact wheel.

I do them with a rotary platen, or on the slack belt just above the top idler.
I suspect you could just remove the platen and grind on the slack belt, too.

Many years back, there was a British Blades chap who was making a flambarge sword. He made a 1.5" wide platen with a slight curve from side to side (opposite of a radiused platen) and the edges rounded. This allows the 2" wide belt to cup slightly as he would grind with no bite at the edge of the platen to cause a divot in the blade.

Another idea would be to make a curved face contact wheel (effectively the same as above platen). Turn down a contact wheel and leave the center 1" area flat and round the edges back a good 1/4"on each side of the flat part. This will allow turning and sweeping the blade without the belt edge digging in. I have an old 10" wheel in the shop with a chunk out of the edge from a grinding accident. Maybe I'll turn it down and see how this works sometime in the future.
 
You must log in or register to reply here.
Back
Top