Edge Geometry 101

A brief discussion about knife blade grind types and edge geometry.

[@FreeAmericaChannel]

Thank you, sir. That is extremely helpful, especially the way you describe HOW the edges are ground, not just their shape. Since I have multiple types of edged tools for numerous different tasks, understanding edge geometry is fundamental. I just had a couple of, "Oh, now I get it!" moments.

[@SonnetGomes]

Thank you so much. This video really helped me understand the issues I had with my decade old kitchen knife. I was able to re-profile the edge and bring it back to shape. It now performs as good as new, if not better.

[@MickyMouseLimited]

Really good explanations about the edge geometry and secondary bevel. I wish all knife manufactures would list this when they sell knifes especially on line it is not easy to see this from just a side picture with no profile. Best Regards Alex

[@QuickhatchKnives1]

Very clear explanation on these different knife grinds, another great teaching video. Thank you.

[@ericwiltse8054]

Thank you Sir, just getting into sharpening. I've been hearing all these terms and wondering exactly what they mean. Very informative.

[@thelert]

Thanks Mike, I have been researching what hollow ground means and I couldn't ask for better examples.

[@cigarcaptain]

Another great video! Thanks for sharing your knowledge

[@kaitheredninja9919]

As always Mike , a very helpful video, thanks .

[@budgunter8950]

Thank you for making simple explanation to the grinds and also explaining a sharp and dull blade; It was VERY informative. By the way ....Yes, it was Very Interesting

[@GRDray]

Good video.Lots of info. It helped me out. Thanks for sharing.

[@KnightsArmory]

This answered a lot of questions I had. Thank you!!!

[@mdoyle403]

Thank you for your time and a great explanation

[@HavenCraftHomes]

Thanks so much - extremely helpful!

[@wrathofatlantis2316]

Glad you like the consistency of hollow grinds when wearing up, the exact same reason I do.

[@dougparkhurst279]

Very concise and helpful. Thank you!

[@tunturikuningas5393]

One good thing about scandi grinds is that the angle of the edge never changes, no matter how many times you sharpen them!

[@dennisleighton2812]

Hi Mike. Yeah, what you say makes sense, especially what you say about the much-maligned hollow grind. When I make my hollow grind blades I grind more steeply than you depict on your illustration - about 1/3 of the way up to the back of the blade. This creates a steeper angle down towards the secondary bevel at the edge and a stronger edge. However it also gets thicker quicker with prolonged sharpening (as you described for the convex grind), and that is a consideration. So, it becomes very important to decide exactly what the PRIMARY purpose of the intended knife is, before deciding on the edge geometry (the point you made). For heavy work I would use thicker steel and make the primary grind narrower and steeper, while for a food prep or butchering knife I would use much thinner steel, probably a flat (or hollow grind going far up the blade) and a flat angle, so one can sharpen it far longer into the life of the blade. The Scandi grind still confuses me. The stated intended purpose is "bushcrafting" - whatever that is. Yet, it is claimed that Scandi grind is King in two main areas - feathersticking and batoning. Now, in my mind why would one use a single tool for two such disparate tasks? For effortless batoning, a large thick blade with a steep grind makes far more sense and would require a fraction of the effort. For feathersticking a sharp blade is required where one needs to be close to the action, so a small blade is better, like for intricate carving. Why make a knife that falls between these two stools? Weight? One hears that an axe and a Scandi knife are all you need. How about a folding saw, a big knife and a small carving knife instead, which could possibly be the lighter option, and still do everything the other could. In the final analysis then, I guess it depends on the individual, and what they like doing. Thanks for an interesting talk.

[@elderyoung416]

Well done. Thank you.

[@DeanO]

Great information

[@Supernaught00]

Thank you very much for making this video, it was very informative.

[@monabo1]

Great video brother,thanks

[@walterlytasz4034]

Great video!

[@kylebates3627]

Thank you again mike, you give a great perspective on edge geometry. Glad to see you're doin okay and still making videos, all the best.

[@dilutedrep2864]

It definitely makes sense . I like a hollow grind better for meat and food prep . Skinning etc.. but prefer flat or scandi for wittling i get better control . and a convex on a machete or a large chopping and batoning knife for splitting wood . A scandi grind splits small pieces of wood better than a flat grind since it is thicker where the grind begins and makes the knife a little stronger than a flat grind. Hollow grinds on smaller knives is usually too fragile for hard uses but like you said you can sharpen it longer with out reprofiling

[@russmeek3213]

Thanks for the reply much appreciated, a.t.b.Russ

[@andrebrazeau-te9ng]

Thisis good for me thank you

[@robertlombardo8437]

Is the best grind for a chef's knife a Scandi Grind? It seems like it might be, like a 10° or a 15° grind. Trying to make one right now.

[@russmeek3213]

For someone like myself new to knifes and associated videos,this has been a great help in understanding the different grind types,so do you match certain types of knife design to a certain grind or can any grind go with any knife?. Any advice you can give will be a great help,thanks Russ

[@BowieMaker]

It is usually just a matter of personal preference or what the customer wants. If I am making a period piece I might do a flat or convex grind rather than a hollow grind as hollow grinds were not as common in the 1800s. And as I said in the video a convex grind is better suited to a heavy chopper.

[@Ruoja71]

When choosing blade geometry I would mostly care about resistance and aesthetics. Any blade can be sharpened more than enough really. Lately I bought a flat bar of steel to make a knife and I accidentally cut myself with it. Surprised, I did the shaving test, and one of the ~90 degrees angle of that flat bar was easly shaving hairs off my forearm. :)

[@natureme2392]

One side of the blade is about 45 degrees and other is more straight. Is it quality control issue and is it fixable.

[@orangpendek1024]

What would be the best blade geometry for a stainless hunting knife?

[@BowieMaker]

+Orang Pendek It is really matter of personal preference . Others may disagree with me but I prefer a hollow grind for most applications because I believe it performs better.

[@alfredosenalle9284]

Hi , what is an appleseed edge ?

[@tunturikuningas5393]

Usually all knives have a secondary bevel, except scandi grind and razor blades, right?

[@44special9]

No secondary bevel on chisel grind or convex grind either

[@rc4688]

What's the difference between scandi and sabre grinds?

[@44special9]

A scandi does not have a secondary bevel but a sabre does .When you sharpen a scandi you lay the whole primary bevel down on the stone and the sharpening angle is already preset for you . When you sharpen a sabre you sharpen the small secondary bevel .

[@timrodriguez1]

🤠👍

[@edwinabbel3783]

And wich is a saber grind?

[@44special9]

Saber grind was the one with the words primary bevel and secondary bevel . The primary bevel goes up about half way , sometimes slightly higher or lower , but never the whole way up . It also has a small secondary bevel ( edge bevel ) that you sharpen .

[@ste.frosttorus9138]

The japanese tend to hollow out the back of a chisel grind to help with resistence and food sticking to blade.