Knife Talk Online Forums
  Home membership Help Search Calendar Members Classifieds Treasury Store Links Gallery Media Center Login Register  
Custom Search
Pages: [1] 2 3   Go Down
  Send this topic  |  Print  
Author Topic: Some Experiments With Blade Geometries  (Read 17471 times)
0 Members and 1 Guest are viewing this topic.
Ed Fowler
Administrator
Trade Count: (1)
Hero Member
*****
Posts: 3448



View Profile WWW
« on: March 28, 2007, 10:58:03 PM »

I have written about the Rudy Ruana blade made in the last 1930's and how it has influenced my thoughts on tatical knives.

I made some 7 to 8 inch knives using the thoughts inspired by Rudy's knife and the one made by Bill Scagel that he called a fish knife. Both of these knives were double ground so that the mid line is most prominent, the spine and edge thinner. Very carefully blended to be a very efficient blade for sticking and slashing. I wondered how this style would work on smaller blades and forged two.

The first blade was about 3 nches long and 3/4 inches deep.



The second blade is about 4 1/4 inches long and 5/8 inches deep.




Both of these blades carry very adequate strength to the tip, both penetrate very effeciently, naturally the longer blade is more effecient than the shorter blade. Penetration is their strong attribute, both are fairly easy to retrieve from being hammered point first into plywood.

While they appeal to me visually they are not truly great knives for every day work around the shop. The angle from edge to spine is too great for slicing work. Is there a compromise between "tatical" and all around use?  Maybe, but I would not chose either of these knives over my usual blade geometry for every day carry.

As luck would have it, one of my aged buck sheep went down and was dying, it was obviously time to put him out of his missery. Shooting a buck sheep is not always a quick death, their skulls are meant to tollerate shock. My best and I feel most humane method is simply cutting their major neck blood vessels with a knife. First I cut one side with my every day gentleman's pronghorn, waited until he died then tried it using the other two blades. The effort was a little less using the experimental blades.

Since cutting throats is not an every day occurance I have to put these mini-tatical blades into the art class. Forging and grinding them is very time consuming and a real challenge. By the time I had blended all the smooth geometry to satisfaction I felt a real sense of accomplishment. To my eye they are beautiful to look at and serve as a tribute to the fighting men of history as well as being more pleasing to me than the double edged dagger.

Thanks to Tena and Phil the photos are above! Yea team!    

« Last Edit: April 22, 2007, 12:53:05 AM by Ed Fowler » Logged

Ed Fowler High Performance Knives
http://edfowler.com/
 
caknives
Global Moderator
Trade Count: (0)
Hero Member
*****
Posts: 592


View Profile
« Reply #1 on: March 28, 2007, 11:20:18 PM »

Hey Ed  It's really cool to hear how those knives came out, You were working on them when I came up for my test. I remember examining the ruana many times and would love to see these little beauties. If you do any other tests with them keep us posted. ( slashing, various penetrations, etc.)
Logged

Don't take life to seriously, you'll never make it out alive.  - Van Wilder
radicat
Guest
Trade Count: (0)
« Reply #2 on: March 29, 2007, 02:03:27 AM »

     Ed, a mini-tactical is exactly what many would like to carry. I'd like to see these blades with an ambidextrous handle in a pouch sheath to drop in the pocket or carry on the belt. What they lack as far as being all-purpose knives is made up for by their strength and beauty.
     Standby for taking orders on these. You may have another production knife with this one.   Clay
Logged
Jose Reyes
Member
Trade Count: (0)
Sr. Member
***
Posts: 120



View Profile
« Reply #3 on: March 29, 2007, 12:44:37 PM »

Hi Ed,

  These look great but I prefer the one with the longer blade. Are the clips sharpened on these? I'm still a novice but the geometry seems well suited and the points seem to be hardened a little further back than usual. Since it's a specialized fighter it might be a good feature to have. Is the extra thickness from the edge to ridge primarily for strength or is it because the ridgeline is closer to the cutting edge? Although I can't figure out a way of doing it without interfering with the "flow" of the grind, and perhaps hampering the thrusting ability, but would it be possible to get the ridge a bit closer to the spine to have a wider cutting edge? Looking them over while I write I get the feeling that would defeat the purpose and I doubt it would look as good...

  I hope you get a chance to take more pics of these once you get the handles on, and maybe show a pic of the Ruana. I'm working the handle on that Bowie down pretty close, even though it still feels a little bit big, but am close enough that I'm sweating removing too much! Grin Will have to get Phil to do another QC check for me and then I'll work on getting a pic up.

Thanks,
Jose
Logged

radicat
Guest
Trade Count: (0)
« Reply #4 on: March 30, 2007, 01:23:24 AM »

     I believe Ed has gotten all a man can out of tactical knives with short (legal length) blades. As a maker he may or may not elect to sharpen the spine edge. Some states forbid double-edged blades. Some allow it, if licensed. The purchaser can sharpen at their own risk of course.
     I suppose a blade about 1 1/2 inches wide would allow a less acute bevel angle and the trade-off for that would be the extra weight. Ed could make a knife like that some kind of pretty too.
     But, don't give him any ideas, because if he did it, we would just have another knife to put on our wish list.
« Last Edit: March 30, 2007, 08:15:31 PM by radicat » Logged
radicat
Guest
Trade Count: (0)
« Reply #5 on: March 30, 2007, 01:31:18 AM »

    Ed, if you post a photo of the Ruana could you try to leave it as natural as possible (a little glare won't hurt) and maybe give us shot of the distal taper  Thanks    Clay
Logged
Jose Reyes
Member
Trade Count: (0)
Sr. Member
***
Posts: 120



View Profile
« Reply #6 on: March 30, 2007, 10:58:13 AM »

Hi Clay,

  The grinds on these look great, and I know from experience how effective Ed's blades are, but since this is a specialist grind the sharpened clip is just a thought. Of course, aside from reading a few articles, I don't know anything about knife fighting...  Grin This is pretty advanced geometry too so I'm still trying to wrap my brain around it. It's a good point that you could also widen the blade, instead of playing with the ridgeline, but from an aesthetic viewpoint I don't think I'd go much wider. I suspect Ed's considered all these viewpoints already though and has concluded this has the best balance.

PS Looking them over again I think I prefer the shorter blade...
Logged

mckenna
Member
Trade Count: (0)
Full Member
***
Posts: 37


View Profile
« Reply #7 on: March 30, 2007, 12:29:12 PM »

You might be on to something here Ed.
Greg
Logged
davidm
Member
Trade Count: (0)
Hero Member
***
Posts: 910


View Profile
« Reply #8 on: March 30, 2007, 01:56:41 PM »

I like the smaller knife too, (ala Ruana "Smoke Jumper").  especially w/ the clipped blade and new grind, really shows off the curves.   Beautiful stuff! 
David
Logged
Ed Fowler
Administrator
Trade Count: (1)
Hero Member
*****
Posts: 3448



View Profile WWW
« Reply #9 on: March 30, 2007, 03:51:08 PM »

The small blades are really excellent if you wanted to punch holes in he sidewalls of tires. Actually using one is not the fun I find using a regular grind blade can provide. I remember an article written years ago called "Bowies as Hunters". The writer tried to find a use for the bowie deisgn other than fighting or art. I tried one on the kill floor and did not like it, I passed it around to the other men working on the floor and they did not like it at first sight. I conned them into using it 'as a favor'. One man said it best when he responded "Have I used it enough now?" no one liked it, but they all felt it was pretty.

Actually I find this style of blade absolutely the most beautiful of the "art knives". It is much more difficult to achieve than the standard dagger. This style has been around for a long time, this is the first I have seen it in a smaller blade. But I would bet that it has been made before.

In larger knives it is an extremely beautiful example of grace, dignity and function as a fighter. Ed Schemp has been using a variation of the double ground blade successfully for years in cutting competitions.
Jose has one, Phill took a beautiful photo of it and posted it in chat last  Tuesday. maybe they will post it here???

The design aspect are very dedicated, much like a shark or well designed sail boat, to flow gracefully in functional elegance. I have seen many, none touched me untill Bill Scagels Mermaid and Rudy Ruana's fighter. Now I see them a lot.
« Last Edit: March 31, 2007, 02:47:20 AM by Ed Fowler » Logged

Ed Fowler High Performance Knives
http://edfowler.com/
Ed Fowler
Administrator
Trade Count: (1)
Hero Member
*****
Posts: 3448



View Profile WWW
« Reply #10 on: March 30, 2007, 09:27:26 PM »

This is a little experiment Butch Deveraux, Eldon Perkins and I did exploring the virtues of a double ground knife.



This is a photo of the experimental blades. One with the double ground geometry (this is the same blade as in the first photo in this thread) and the other one of my standard blades of about the same volume. They are marked at 1/2 inch and 1 inch from the tip.


Butch pounded them into a piece of plywood about 2 inches thick.
First to a depth of 1/2 inch then to the second mark at 1 inch.


Butch drove the blades into the plywood to a depth of 1 inch.
[hIMG]tIMG]
Eldon pulled them out by hand.

]

These are the tracks the blades left in the plywood. First they were driven in only 1/2 inch, then to a full 1 inch. This is why the holes left are of different size. The diamond shaped holes by the double ground blade, the v shaped holes by the convex blade.


What we found: The double ground blade penetrated much easier than the convex ground blade. The double ground blade was also easier to remove from the plywood.
« Last Edit: April 21, 2007, 10:19:53 PM by Ed Fowler » Logged

Ed Fowler High Performance Knives
http://edfowler.com/
radicat
Guest
Trade Count: (0)
« Reply #11 on: March 30, 2007, 10:34:41 PM »

   It may seem like a simple test, but the result presents more questions. I noticed this phenomenon myself in just hand stabbing 2 by 4's. But, I wasn't sure because the handle on the better penetrater was better. I  have thought for some time that the double edge allows the blade to shift, reducing drag, whereas the flat spine acts as a stop to prevent that side shifting.
    I wonder if a jig could be made to hold the blades in a fixed position and the plywood allowed to shift as the blades are driven? Then, a measurement of the plywood's movement might verify my thinking. Oh, no, I might be getting the test bug!! I heard that the Chinese are trying to develop a vaccine to stop it from spreading. They don't want to have an epidemic of good knifemakers on their hands when they take over.
Logged
Ed Fowler
Administrator
Trade Count: (1)
Hero Member
*****
Posts: 3448



View Profile WWW
« Reply #12 on: March 30, 2007, 11:11:59 PM »

You have probably noted the geometry of these blades is very much on my mind. I have been actively experimenting with it since last September and thinking about it long before that.

As a pure fighter, wow stuff. As a utility blade they leave a lot lacking. for example: To open a soup can with one is not fun, a paint can with a press down lid is a problem also. With the usual convex grind you can lever the tip into a can or lid, the mid line makes this difficult.

Like most of us feel, they sure are pretty!!!

I am still working with the geometry, some minor variations, but not very promicing.
Logged

Ed Fowler High Performance Knives
http://edfowler.com/
Harold Locke
Member
Trade Count: (0)
Hero Member
***
Posts: 599


View Profile WWW
« Reply #13 on: March 31, 2007, 12:53:46 AM »

Ed,

Hope you don't get tired of hearing it. Both of the blades are absolutly beautiful to the eye. It is going to take some time and a lot of looking and thinking on my part to grasp it. I like the bigger blade and I wonder will that beauty keep when the size and depth are increased. I do believe that is took some major work to accomplish to the end.

The pictures of this blade also shows me that there is beauty in the patterns revealed by the etching. The knives I have done so far have been sanded to a 2000 grit finished and polished back to whatever the Jackson green compound grit delivers. This was one of the points that I didn't think I agreed with from my earlier readings of your works. It is all starting to make sense. 1) The importance to a good restful sleep that you  as a knifemaker know that you have delivered a product that is all it can be. 2) Wow it is just nice to look at as you study the blade details.

In addition the test reminds me of a quote attributed to Gen. Patton that I read somewhere. I think it might have been from one of Wayne Goddards works of even yours.

The only real purpose for a double edged sword is so that it can be withdrawn easily. I think there was even a reference to the impracticality of the backwards slash?Huh? Truck Driving is melting my brain.

Great Work, Thanks for Sharing

Harold Locke
Logged
Ed Fowler
Administrator
Trade Count: (1)
Hero Member
*****
Posts: 3448



View Profile WWW
« Reply #14 on: March 31, 2007, 02:59:40 AM »

"The saber of 1913 is two edged. All of the front edge and half of the back edge is sharp, so that it may be more easily withdrawn from a body, and also on rare occasions to cut."  Prepared by Second Lieut. George S. Patton Jr. "Saber Exercise 1914" War Department: Office of the Chief of Staff"
Logged

Ed Fowler High Performance Knives
http://edfowler.com/
Pages: [1] 2 3   Go Up
  Send this topic  |  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
TinyPortal v0.9.8 © Bloc
Valid XHTML 1.0! Valid CSS!