First Chef's Knives

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gatorforge

Joined
Jul 2, 2010
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So I have a bit of experience making knives, but I've never made kitchen cutlery. I do stock removal , not forging, and have some 3/32" W2 coming in for this project.

I was wondering about grinds for them. Many chef's knives I see do not have a plunge or grind lines typical of what I'm used to making on outdoor type knives. Are people full flat grinding and hiding their plunges under the handle, or with stock that thin is there really no plunge on a full flat ground knife? Are people typically saber grinding, then blending the grind lines to flush them? Also, what Angles are people typically using for their main bevel?

I know this will take some practice, but I've got time between now and Christmas to screw up a few lol.
 
Just grind it FFG and sweep the plunge.

Start by grinding the bevels and stopping just before the plunge area, but don't make a defined plunge. Once the basic bevels are set, grind towards the ricasso and don't stop at the plunge. As you reach the place where the plunge would be keep moving and turn the blade while lifting the pressure to make a smooth transition. It is simpler to do than the description sounds. Try it on a bar of scrap steel and you will get it down fast.
 
Thanks Stacy! That's a big help, and similar to how I have done false edges on the tops of some of my knives. Honestly I feel dumb as that is a lot simpler than the way I had thought to hide the plunge lol.

Is there a good calculator for grind angle based on blade height and thickness? Typically I have done it by eye, but 3/16" has a lot more room for error than 3/32"
 
After HT, grind from the spine to the edge, leaving an edge around .005" . The actual angle is insignificant. Then sharpen at the desired angle. I do kitchen blades at
12-15DPS.
 
In addition to Stacy's tips, I would also encourage you to try giving it a bit of a convex grind. I like to stop the grind about 2/3 of the way up the blade, then switch to a soft platen (mine is leather over a piece of 2" steel) and blend the flat into the primary bevel. You can also do this part during the hand sanding process with a bit more elbow grease. It helps reduce friction during the cut and aids with food release. Vachon knives has an excellent grinding tutorial about all this in an IG story highlight that I found extremely helpful.
 
Don't forget to grind a distal taper. In the video, he does it simultaneously by focusing pressure more at the spine near the tip. It is very subtle, but that is how most people freehand grind.

I use a jig for distal taper and roughing the primary bevels. I do taper first, then bevels since the angles of the jig are different. After that, I blend it all freehand. This results in a very flat, but slightly convex (almost imperceptible) blade with most of the convex being close to the spine.
 
gatorforge said:
Thanks Stacy! That's a big help, and similar to how I have done false edges on the tops of some of my knives. Honestly I feel dumb as that is a lot simpler than the way I had thought to hide the plunge lol.

Is there a good calculator for grind angle based on blade height and thickness? Typically I have done it by eye, but 3/16" has a lot more room for error than 3/32"
Click to expand...
I have used this online bevel angle calculator with success.

Online Knife Grind Calculator - D. Comeau

A handy online tool for the knifemaker to determine the angle to use when grinding single or double bevel blades.
dcknives.com
 
gatorforge said:
Thanks Stacy! That's a big help, and similar to how I have done false edges on the tops of some of my knives. Honestly I feel dumb as that is a lot simpler than the way I had thought to hide the plunge lol.

Is there a good calculator for grind angle based on blade height and thickness? Typically I have done it by eye, but 3/16" has a lot more room for error than 3/32"
Click to expand...

Chart of Blade Angles for Flat Grinds.

Chart of blade angles for Flat Grinds. I thought I would share this with everyone. I know that many of you can eyeball everything and it turns out spectacularly. But I find that I think, sketch, measure and draw things many times over until I can visualize it properly and get close to...
www.bladeforums.com www.bladeforums.com
 
Do a full flat grind with a distal taper to it. Get some F3 felt from Amazon (1/4" thick is nice) and use double sided carpet tape to attach it to your platen. It will give a nice even convex as you push into it and will allow you to get a nice belt finish as well. The softer edges make it easy to blend the plunge cuts, too to they are more gradual.
 
I say it regularly:
Forget about calculating the blade angle for a FFG. It doesn't matter. The blade bevel angle is a fixed factor of the height and thickness of the blade.
Pick a stock thickness that fits the knife's size/use, then pick a blade height that fits the knife size/use. These two things will set the angle.
Grind a distal taper of at least 50% the spine thickness. This means the thickness at the handle is about twice the thickness an inch from the tip. Many delicate slicing knives have a 75% distal taper.
1) The spine thickness and the blade height are going to determine the angle ... you can't change the angle produced by that.
2) The distal taper changes the angle as it gets thinner ... you can't change the angle produced by that.
3) The blade height usually is reduced as it approaches the tip ... you can't change the angle produced by that.

The only angle you can control is the edge angle (sometimes called the secondary bevel) in sharpening. The lower the edge angle the finer the cutting ability. Too low and the edge is unstable and may roll or chip. Too high an angle and the edge will wedge while cutting. You have to pick an edge angle that fits the steel, HT, and use.
 
I agree with Stacy. I’m a nerdy engineer/scientist (as many here know 😊), and on my first kitchen knife, I rubbed my hands together (figuratively) and said “hey, I can do trigonometry”. I have done that once and only once. Overall appearance of the knife (which adds to its appeal and value) is far more important than the calculated angle. Also (and more importantly), at least as I have experienced it, a very small thickness behind the edge (regardless of the bevel angle) is FAR more important to performance than is the bevel angle…
 
Thanks for all your help guys, the W2 came in today so I’m going to get my patterns cut out and be digging back through this thread and watching all the videos.
 
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