I think you will find this a matter of opinion. Your estimation sounds reasonable to me. If the knife is used strictly for skinning, it can be pretty thin. I have made some .080 for a full tang hunter but as thick as .250 if it is a general use utility that will see some rough use such as batoning. Both can be used for hunting but will have their strong points.

This is where testing comes in. As in the case of a bowie for instance, only by using it for it's intended purpose will you know. The cutting competitions really allow a maker to test different thicknesses and designs.

As long as we can agree that this is a matter of personal taste.........I think that if it looks right, it is right. <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//laugh.gi f' class='bbc_emoticon' alt=':lol:' />

I am very fond of right around 5/32" for general use/utility in almost all my single edge blades. A longer blade goes a little fatter, a smaller one, a little thinner. I hover right around .150.

Kitchen and chef's blades are the thinnest, no matter how long they are. (unless we are talking about specialty knives like leather worker's blades, or something)

Double edged (daggers) and the ricasso gets much fatter, up to around .25, unless it's intended to be a small concealed carry knife.

Like Lin said, it all depends on the intended use, and personal taste. I once made a small hunter on commission, 4 inch blade, full tang, and the owner wanted the blade around .25 thick and 1-1/4 wide. I think it's way too fat for the size knife, but he has assured me that when it comes to cutting up the elk, that knife works great. I went hunting with him last year, and offered to make him a new one. I even offered to take the old one in on trade at the full price he paid, and he refused. Go figure.

We got rained out on that hunt and I never did get to see it in action, so I have to take his word on that.

One critical point in determining proper spine thickness is breadth of the blade, that is, distance between spine and edge, as that will determine the angle of the primary bevel. Consider the blade in cross-section, think of its intended use and then determine the proper trade off between cutting efficiency and strength. One of the reasons chef knives are both thin and wide is that this geometry allows for an incredibly acute bevel angle, which improves cutting efficiency tremendously. This is an important consideration when designing knives for actual use.

I am also of the opinion that many customers and makers today tend to be biased towards excessively thick "bomb-proof" blades, and compromise cutting efficiency as a result. A properly heat treated blade of modern steel, using precise, controlled heat treat methods, and drawn back along the spine can be incredibly strong and tough without having to be excessively thick, cumbersome, and heavy. I would argue that for the vast majority of uses, anything over 3/16 is too thick. This was not always my view but after making, testing, and using knives for many years now I have come to believe that thinner is often better, especially where cutting is concerned.

This is too thick! This is too thin! Only takes on meaning with each individual knife in it's actual use.

A kitchen knife is usually very thin because a full slicing movement keeps the full blade in the cut. Or not; as in a rocking type chef knife.

But a skinning knife on the other hand usually uses the very last part of the cutting edge; almost no bevel interaction at all. Unless it's used to slice after skinning.

A chopper is made to the stuff you are chopping; sometimes thicker, sometimes thinner. Hickory cuts different than bamboo.

As stated earlier; we must test and prove our design to function. Blade thickness is only a factor of design unless it inhibits or improves function.

Generalizations are for those who do not create, test, and observe the long time use of their work.

two cents worth.

As you can see from the responses, much of this is subjective. The main thing to remember is how is the blade going to be used. You understand blade geometry as much as anyone and what thick vs thin can do for the usability of the knife. Something that will teach you more about blade geometry than anything else is cutting competitions which you have done. Make a thin, light blade and a heavy, thick one and see which tasks each does best.

Gary

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One critical point in determining proper spine thickness is breadth of the blade, that is, distance between spine and edge, as that will determine the angle of the primary bevel. Consider the blade in cross-section, think of its intended use and then determine the proper trade off between cutting efficiency and strength. One of the reasons chef knives are both thin and wide is that this geometry allows for an incredibly acute bevel angle, which improves cutting efficiency tremendously. This is an important consideration when designing knives for actual use.

I am also of the opinion that many customers and makers today tend to be biased towards excessively thick "bomb-proof" blades, and compromise cutting efficiency as a result. A properly heat treated blade of modern steel, using precise, controlled heat treat methods, and drawn back along the spine can be incredibly strong and tough without having to be excessively thick, cumbersome, and heavy. I would argue that for the vast majority of uses, anything over 3/16 is too thick. This was not always my view but after making, testing, and using knives for many years now I have come to believe that thinner is often better, especially where cutting is concerned.

I agree with much of what you said Derrick. After many years of testing steel as a material, studying it inside and out, I would say that the benefits in thicker cross sections would be mostly in weight and mass distribution or functional geometry, not strength considerations when using a knife as a knife. When I handle a knife that is so massive at the spine that I can feel how tiring it would be to wield after just a couple of swings, I always want to ask the maker (but still keep it to myself) what it is about steel they do not trust. There is a reason that our civilization, from an engineering standpoint, is based on steel; it is incredibly strong stuff. The one area where very thick blades offer more in strength is in using the knife for a prybar, but I have always rejected that concept out of hand because I am a knifemaker, and prybars are cheap and made for that job. I had a prybar once that I sharpened on one edge and cut a rope at the Ashokan seminar to illustrate a similar point, that prybar was miserable to use after that because it had that sharp edge, its primary function had been totally compromised by the distraction of trying to use it like a knife... well, vice versa...

Obviously for mass distribution we must play with thickness but I have seen some large knives that were so heavy that an axe would be a much more effective and elegant tool to use. While on the flip side I am always blown away by how thin or light in the hand real swords are, I have yet to handle a well made one that didn't feel great. Which brings us to an important factor that has yet to be included in the discussion- how effectively we use thickness in mass distribution; in other words how important it is where we put the thickness. With proper tapers and geometry a fairly thick spined knife can still feel fairly light in the hand.

With proper tapers and geometry a fairly thick spined knife can still feel fairly light in the hand.

I agree with your statement Kevin. Would it therefor be reasonable to say that a lighter weight knife who's weight/material distribution is poor would feel heavier than the one who's distribution is well done but is technically a heavier knife? I say yes.

Balance is the key.

Thank all of you for the input. It will give me something to think of while forging my blades.

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This is too thick! This is too thin! Only takes on meaning with each individual knife in it's actual use.

A kitchen knife is usually very thin because a full slicing movement keeps the full blade in the cut. Or not; as in a rocking type chef knife.

But a skinning knife on the other hand usually uses the very last part of the cutting edge; almost no bevel interaction at all. Unless it's used to slice after skinning.

A chopper is made to the stuff you are chopping; sometimes thicker, sometimes thinner. Hickory cuts different than bamboo.

As stated earlier; we must test and prove our design to function. Blade thickness is only a factor of design unless it inhibits or improves function.

Generalizations are for those who do not create, test, and observe the long time use of their work.

two cents worth.

whats the difference between a rocking type chefs knife and a normal one? i always use the wave chopping method when i use one and would like to know what the difference is when i finally get around to make myself one. I always keep the first knife i make when doing a new shape or trying a new technique =). ya here i am with around 8 months and off and on of experince and 17 blades made, and im talking like i have been making blades for years.

|quoted:

As you can see from the responses, much of this is subjective. The main thing to remember is how is the blade going to be used. You understand blade geometry as much as anyone and what thick vs thin can do for the usability of the knife. Something that will teach you more about blade geometry than anything else is cutting competitions which you have done. Make a thin, light blade and a heavy, thick one and see which tasks each does best.

Gary

Just one little problem with this... I never learned geometry beyond basic shape theory. Any links or for "Geometry for Bladesmiths" would be would of great help great.

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I agree with your statement Kevin. Would it therefor be reasonable to say that a lighter weight knife who's weight/material distribution is poor would feel heavier than the one who's distribution is well done but is technically a heavier knife? I say yes.

Balance is the key.

I get that know. i working on my first 'short sword' length blade that is 19 inches over all with a 6 inch handle and 2 3/4th inch riccoso and 10 and 1/6th inch blade made form leaf spring. despite its length its balance makes it feel light. balance does need to be taken into the equation. however, i do not know enough about geometry to properly asses designs by the numbers alone, so i have to do it by feel, luckily I have a somewhat good sense of feel so i can judge it fairly good.

I'll occasionally use 3/16 for 4.5" drop points, but it's boarder line for that, and too thick for anything smaller as far as I'm concerned. Not to mention (again only my opinion) that a 3/16 full tang knife looks terrible unless it's a tapered tang. I usually like 1/8" stock for most knives that'll actually be used. I've used 1/4" on occasion, but mostly for large parang like choppers, and hollow ground Bowie's that are more of a belt decoration than something that'll see serious use.

I'll definitely agree things are trending towards too thick of a blade.... I saw one maker selling paring knives made from 3/16 stock with a fairly steep and axe Li convex grind.... I'll usually start with 3/32 for a paring knife and grind it damn near paper thin at the edge, full flat grind. I guess I generally take the view that a knife is for cutting, not prying fence boards off