Knife Design... Where is the tip of the knife supposed to be?
Posted 05 August 2011 - 05:58 PM
Where is the tip of the blade supposed to be?
Yeah, I know, sounds pretty smart-butt. I understand it breaks down into blade use, types for use, hand size, and on... goes on to tip(and/or edge) shape and connects to other aspects of blade/handle from there.
In some ways, I'm looking to find out what anyone knows from personal, observed, or studied experience... and I don't care what knife (etc.) form, at all. You feel you understand something or have sound reference here, I'd really like to hear it.
Posted 05 August 2011 - 08:23 PM
Well and this is going to sound "smart butt" as you put it. It depends on the design of the knife, by that I mean style of knife. Whether it is a drop point hunter, or a trailing point hunter, or an upswept point hunter. On bowie knives, is it a spear point, or southwest, or a standard bowie with straight clip. Perhaps you are making a viking scramasax where the point is very low in relation to the blade edge or in line with it. I know not an easy cut and dried answer. I think it comes down to the percieved concept of what the particular style of knife looks like. Say you make a hunter and you place the point way down towards the edge. You may call it a drop point hunter and it is because the point really drops. BUT, the buyer will say, Oh you made a wharncliff style blade.
You can look at the past issues of Knives Annual or Blade magazines and just look at the knives and different styles to get ideas.
I guess there are certain unspecified guidelines to styles of knives that you learn by looking at knives and reading about historical knives.
I usually go by what I have seen or read and what looks right to me. I guess you could call it an artistic sense or license. I will also draw out designs if I have an idea for a knife to get an idea of what it will look like before I make it.
I hope this gives you some ideas and starts to answer the question.
Anvil Top Custom Knives
Posted 06 August 2011 - 08:25 AM
From my last paragraph... In some ways, I'm looking to find out what anyone knows from personal, observed, or studied experience... So, I guess what I'm thinking about is use... that, related to tip and/or edge position and shape.
When I started the thread I was thinking about hunting knives, hawks, smallish defense knives, and what their tips/edges have to do with hand position and use.
Like a hawk's edge... straight, curved, how curved, angle to line of handle, and on. Or your example of drop point ranging from just barely to "wharncliff"... each of those extremes of drop, and all in between, can be defined by use characteristics.
Posted 06 August 2011 - 11:30 AM
Sounds like you're talking about trying to arrive at a personal understanding or some principles of blade design and usage or application in relation to the handle and the human hand and body ergonomics. Well, that's what I ponder from time to time anyway. It's a topic or aspect of knife making that is a bit more difficult to ferret out than construction and shop techniques like forging and grinding.
I just attended a workshop on knife design JD Smith (a mastersmith) gave at the hammer-in in Maine. One thing he specifically talked about was form following function and we need to study and understand how the knife will be used. Will it be piercing, stabbing, swinging, skinning, fighting, etc.? He pointed out some application are "up close" like skinning while others have more distance like fighters. He suggested we study lots of knives throughout the cultures of the world and carefully construct our own personal vocabulary and judgment of knife design.
Ed Fowler is a maker that seems to have done something like that. He certainly has strong convictions as to what makes a good knife and how it should be shaped and bladed and handled, etc. Even if you don't agree with all his conclusions you can certainly appreciate his efforts at arriving at them and articulating them! Here's a link to his contribution in a discussion on handle shape, http://www.bladeforu...954#post2902954.
Here's a link to Haley DeRosiers (a journeyman) comments on blade shape re the recessed ricasso http://www.americanb...indpost__p__713. I believe it represents the process you are asking about regarding drawing conclusions about blade design based on observation and experiences.
For my part, I have been making a study (admittedly anemic) of the hand: from modeling it, to reading on ergonomics, to simple observations and reflections. Here's a link to rather involved study you might get a kick out of, An ergonomic approach to oyster knife design and evaluation.
Good luck and keep us posted as to your efforts and any good sources, info or conclusions.
All the best, Phil
Earth Crafts & Applied Arts
www.eartharts.us (update pending)
Posted 06 August 2011 - 07:39 PM
Not so much ergonomics/"in relation to the hand" as blade use... where tip is, shape, edge for use. I've tended to put the tip on the center-line of the hand for knives... feeling the hand instinctively knows where the tip is. Small game knives have sharper tips, usually, and an easy way to do that is having the tip sweep up above the spine. The tip area can be shaped that way and the tip can still be on the CL of the hand. That's the kind of thing I'm curious about and wondering what other's know about it.
Added... I really liked the oyster shucking pdf. Kind of humorous the ergonomic solutions totally missed the blade needs to be longer to be used safely. You don't happen to have oyster shucking part 2, do you?
Posted 08 August 2011 - 08:03 PM
I would think it would depend a lot on the knifes intended use. Take a fighter fo example,If the intended use is thrusting, than having the point on a center line with the hand would make sense. However if you have a blade which is used for carving, say a turkey, the point would be better above the center line of the hand in order to take full advantage of the edge. More of a slashing motion.
One of my areas of interest is historical swords. The earlier cruciform swords, like viking swords had the point in line with the handle, consequently they were used mainly for thrusting with a slash or cut being secondary. Then you look at cavalry swords. They were used mainly on horseback and had the point raised above the centerline to make a slashing motion more effective. Japanese swords are also used mainly for a cutting or slashing motion, again the point is above the centerline with some exceptions. A curved blade with the point raised is more effective for this type of use. It is interesting to see the development of swords over the centuries. Same with knives. Now we have so many different types. They have evolved to meet many specific needs.
Something to take into account when maing our knives is how they will be used by the customer.
Good stuff Mike.
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Posted 09 August 2011 - 10:17 AM
Assume you know this site My Armoury
"I would think it would depend a lot on the knifes intended use."... Yeah... methods of use along with, too.
When I very first tried to put a knife on a piece of paper, I found all the pictures of knives I had been looking at to not be much help. I couldn't draw a particular knife correctly with out some kind of reference lines... like a line through center of handle and line along general trend of handle top-line. The first knife I did that with was a classic Cleston Sinyard hunting knife. For what the knife looked like (it's impression), I was dumbfounded to find those two lines met at the tip. The same was true of two other Cleston Sinyard hunting knives... not just circumstantial, I feel.
Anyhow... that's how I started getting curious about "where's the tip". Anymore, every knife I see I have some level of interest in gets lines on it to try to understand it.
Posted 10 August 2011 - 07:08 PM
"One of my areas of interest is historical swords. The earlier cruciform swords, like viking swords had the point in line with the handle, consequently they were used mainly for thrusting with a slash or cut being secondary. Then you look at cavalry swords. They were used mainly on horseback and had the point raised above the centerline to make a slashing motion more effective. Japanese swords are also used mainly for a cutting or slashing motion, again the point is above the centerline with some exceptions. A curved blade with the point raised is more effective for this type of use. It is interesting to see the development of swords over the centuries. Same with knives. Now we have so many different types. They have evolved to meet many specific needs."
I hesitate to disagree because I'm a real beginner here, but I thought that the Viking sword and similar (anglo-saxon, irish) were cutting weapon, hence the more rounded tips compared to something like a Roman gladius, which was designed to stab? See closeup of the Sutton Hoo recreation in the British Museum (if I can get my pictures to load).
sutton hoo sword 2.jpg (33.15K)
Number of downloads: 0
It's got a wide tip comparatively and some of the other blades there and at Royal Armoury at Leeds were actually rounded. That would also agree with the sagas where swords were reported to lop off limbs and "seek the breath line." I thought thrusting blades developed later, partly in response to better armor. You can of course get into the whole cut versus stab argument like Silver did. I can dig out some references if you'd like.
I was also under the impression that the curves of the tachi/katana developed similar to the saber curve, on horseback. I'm not sure about the dao, although I read that some of the dao shape came from the Japanese blades imported in certain periods.
I have found that getting to see actual historic blades after surviving the ABS basic class was real enlightening. It's like a learned to see. Heck, even watching a chef use a kitchen knife shows stuff about design I hadn't considered before.
John Updike - The Dance of Solids
Posted 10 August 2011 - 08:00 PM
Actually the katana developed from the tachi and the tachi from older swords, some of which had straight blades. And yes the tachi did develop the curvature in order to be more effective from horseback and in slashing. As for the burmese dha or dao, it is possible that it was derived from japanese blades. There are some similarities in the style and in the way they are used.
I agree, actually seeing or holding some of the old blades is an eye opener. When you hold a 400 year old katana in your hands you realize that the smith that made it knew a lot about design and everything else concerning their craft. Same with an original woodhead bowie. Amazing what they accomplished.
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