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David Kite wrote:
Awesome explanation Peter. Wow, thanks.

Couple of specific questions, though.

1.) Do you really think duct tape mimics skin that well? I've heard of it being used before, but given that the glue is very sticky I figured that a) it wouldn't be a very educational target, and b) that the glue would be a real pain to clean from the blade. Also, do you use only a single layer of tape, and is it tightly wound?

2.) Is fusiotherm pipe only available in Germany? Or do you know of anything equivalent to it if it isn't available elsewhere?

Thanks

David Kite
ARMA in IN



Hi David,

I can´t say that the target I suggested is *exactly* like a poor human body, only that it approximates more closely than most other test cutting materials used. (apart from the obvious pork chops...)
The glue in duct tape does not hinder so much as the layer is very thin. It is different with a solid gelatinous material without a lubricating fluid (like ballistic gelatin).
You need some tape to bind the news paper down. Duct tape is one option, but you could perhaps use some other adhesive tape that is thinner and less tough if you like. Experiment and see what works best.
The real issue is to find a good plastic pipe to mimic living bone. That is the hard part.
You can then vary the donmension of the pipe and the amount of paper to vary different target areas.
Fresh vine or some other semi hard fast growing plant could work very well. Especially if it has a hollow or porous centre, as suggested above. Only be sure to use freshly cut vegetable matter for this application. It makes for a great difference.

The main idea is to get close to what could be thought as realistic. It is sometimes a good idea to use a realistic target instead of soda bottles, just to hav something to correlate to. No need to get too gory with these cutting practises (unless you absolutley want to, but then make sure no one with easily offended feelings is watching!). The idea is only to get a proper perspective on cutting performance and the dedication and finesse needed for various cuts described in the fencing manuals. What is needed for a cut to be effective?How much movement and force? What speed? What is possible with different types of swords? What is the pros and cons with various designs through the ages. Much can be learned through this.

Unfortunately I do not know of an American equivalent of this plastic pipe, but we are working on it at Albion to look it up. I brouight with me a length during the latest visit.
I will keep looking and post the reslt on this forum when I find the material.

Fusiotherm is available in Sweden, so I guess you could get it in all of Europe?
I think the pipe is probably polypropylene, from the description.
Geoff Wood wrote:
I think the pipe is probably polypropylene, from the description.


Apparently Fusiotherm is a layered composite material.

http://www.kuysen.com/piping/

I'm not aware of a similar product for sale in the USA, but maybe there are some plumbers or builders among us who are.
Steve Fabert wrote:
Geoff Wood wrote:
I think the pipe is probably polypropylene, from the description.


Apparently Fusiotherm is a layered composite material.

http://www.kuysen.com/piping/

I'm not aware of a similar product for sale in the USA, but maybe there are some plumbers or builders among us who are.


Aaah, well found! I confess I was just guessing based on the properties described. We used to cut polypropylene syringe barrels that behaved somewhat similarly.
Steve Fabert wrote:
Geoff Wood wrote:
I think the pipe is probably polypropylene, from the description.


Apparently Fusiotherm is a layered composite material.

http://www.kuysen.com/piping/

I'm not aware of a similar product for sale in the USA, but maybe there are some plumbers or builders among us who are.


it is still poly-propyline based.

Quote:
In the beginning of the eighties aquatherm, in cooperation with its raw material producer, launched a weldable Potable water-pipe system made from polypropylene which introduced the German company into the world market.


Alexi
Aaron Justice wrote:
Patrick brings up a good point about cutting mediums and real life application. An Atrim of course is an excellent cutter, as are most swords with proper geometry and edges.

But what chance are you going to get to, "Well, let's see, stand still Sir," *places the edge on the guys neck to figure out distance* "Now, let's test the COP" *hits pommel and watches blade wiggle* "Okay, right there... now stand still..." *Decapitates opponent*.


Hey Aaron!

Good point!
Cutting a mobile target that puts serious effort into not being hit is of course something else than severing rolled up newspapers :D

As you bring up the conept of COP I thought I´d add some thoughts on that matter here in this thred as well (I hope I am not hijacking the topic...).
Please note, this is my take on it. I am sure not all will agree with these observations.

The COP is usually identified with the placing of the node of no vibration of the blade.
To me the nodes on no vibration offer a way to manipualte the stiffness of the sword during a cut. In popular understanding this has to do with the concept of "harmonic balance". As time has gone by, this term has been stretched to cover so many different aspects of a swords performance, it has almost lost its meaning. When vibration nodes are in focus I personally prefer to talk about node placing, as this is a more precise description.
It seems that a common notion is that the placing of the blade node is of great importance for the cutting performance of the sword. I am not so sure about that. I do not think the blade node and the COP are the same thing. They may coincide, but this is just coincidence resulting from other aspects of the design of the sword.
I´d say it is more important to note where and how the vibration nodes are placed in the grip, or hilt area.

Try this out:
Grasp the grip of the sword and hold it point upwards. Tap with the heel of your hand untill you find the node of the blade. You will notice how the whole blade becomes stiff and vibrates less as you tap in the spot where the node is. From a wobbly flexible blade it suddenly becomes more like a stiff plank.
This offer us a clue to why the nodes play a role in the design of swords.
The node is a place of stiffness where you can manipulate the rest of the sword without causing vibrations. Hence it seems to me that the nodes in the grip, that you will always grasp, are more important than the nodes in the blade. I say node*s* since there are vibrations of higher pitch with nodes placed on each side of the primary nodes in the blade and grip. These are not always aparent, but can be used to some effect in stiffening especially flexible or long blades.
When cutting with a sword during an "agressive encounter with an enemy" you will not only use the part of the blade where the node is, you will cut with a longer section both inside and outside the blade node. *But* you will always grasp the the hilt in much the same place, and by doing this you impart highest possible stiffness in the blade druing a cut, if the placing of the nodes in the grip are optimal.
Again, one must be aware that this is not a rule that has precedence over other aspects of the function of the sword. I have seen (original)swords that have their grip node placed *in front* of the guard. A strange and confucing thing to us modern aficinados, but it sems to work on certain types of sword. One of my most agressively cutting swords had the "grip" node placed 10 mmin front of the guard. This is clearly not according to the rules of how things should work. My guess is that the secondary nodes are put to good use in these instances. More research is needed here.

COP has more to do with pivot points, and this is something else completely from vibration nodes.
The no-shock effect that good swords are associated with is less an effect of the placing of the vibration nodes than the correspondence between pivot points in the grip area and the blade. (both these work together to some extent, but the vibration nodes are primarily an aspect of stiffness and only have a secondary effect on shock dampening)

Placing of pivot points also have a big effect in the intuitive feel of the sword and what part of the edge/blade you get a direct dynamic feedback on through the hilt as you move the sword.
-A feeling of "floating in the air" and "extention of my arm", is a result of effective use of the pivot points.
-Does the blade pivot close to the vibration node as you move the hilt back and forth from guard to guard, or does the point seem to hover still in the air without moving from side to side even as you shift guard? You will see both these situations and everything in between on different types of swords. This is something you adjust according to the intended function of the sword.
These are very important charactersitics for the feel of a sword. Much more important than where the balance point happens to be placed. (although this will of course have some effect as well).

Of course Point of Balance, Placing of Nodes and Pivot Points all correspond with each other.
If you want to shift one aspect without moving the others too much you need to work with the shape/dimension of the blade or lenght of the hilt.

So, my take is this:
Just as the placing of the balance point used to be a main concern some years ago, now there is a focus on where the nodes are placed. Both these aspects will tell you something of how a sword feels and performs, and are important in their own right, but they do not tell the whole story. The key to the dynamic balance, or intuitive feel of a sword lies in the placing of the pivot points. These also has a lot to do with how a sword delivers a cut. Pivot points, Node points and balance point are all spearate entities, but do have an effect on each other.

If you want a sword that is more forgiving in what section of the edge you can use for best cuting reults, you want a sword where the corresponding pivot points from the grip are placed far apart in the blade.
This is difficult to do in a slim and flexible blade with little variation in the distal taper. This is one aspect that non-linear distal taper hepls in more ways than one.

By corresponding pivot points I mean this:
imagine the part of the grip you hold that is closest to the guard, or most forward to the point. If you grasp this place sideways (edge to edge) between your thumb and index finger in a loose grip and "wiggle" the sword back and forth you will notice there is a section of the blade that hangs still without wiggling. This is a bit similar to finding the spot of no vibration in the blade, only that you do not slap the pommel. Instead you move the grip back and forth in a loose grip so that the part you hold can pivot between you fingers. (this is a quick and dirty way of doing this, but it works)
You will find that the corresponding pivot point in the blade from the piovot point in the front part of the grip is placed somewhere between the vibration node and the point. Depending on how far towards the point in the blade this pivot is placed the sword will offer more or less precision in its point controll.
If you now grasp the grip where the heel of your hand typically is when you wield the sword and repeat the wiggle test, you will find there is another pivot point in the blade closer to the hilt that correspond to this place futher back in the grip.

You have now established where the extreme grip pivot points in the grip have corresponding pivot points in the blade. Typically there will be a longer distance between the pivot points in the blade than the distance between the pivot points in the grip.
This will tell you roughly where you will make the most efficient cuts. But do not take this too far as there are other factors having an impact on this as well.

Quite a mouthfull, this! :blush:
These are some of the ideas I´ve been working with in the development of the NextGen swords. I keep revisiting these aspects every time I document a new sword, so ideas are adjusted as time goes by. That´s the nature of this game, I´m afraid... :\ ;)


Last edited by Peter Johnsson on Wed 27 Oct, 2004 5:17 pm; edited 1 time in total
Steve Fabert wrote:
Geoff Wood wrote:
I think the pipe is probably polypropylene, from the description.


Apparently Fusiotherm is a layered composite material.

http://www.kuysen.com/piping/

I'm not aware of a similar product for sale in the USA, but maybe there are some plumbers or builders among us who are.




Thanks for loking this up!
Wow. I'd like to thank PJ for weighing in on this. Getting from cutting plastic 2 litre bottles to the harmonics of medieval swords is precisely why I post here. I'd also like to thank you guys for the cutting medium suggestions. Now I finally have a use for the Daily Nexus. (Free university newspaper)
Peter, thanks for sharing your knowledge with us. I hope for your own sake you are a faster typer than I am. I would have spent the best part of an hour writing a post that long. And it wouldnt be half as interesting if I did. :D
Einar Drønnesund wrote:
Peter, thanks for sharing your knowledge with us. I hope for your own sake you are a faster typer than I am. I would have spent the best part of an hour writing a post that long. And it wouldnt be half as interesting if I did. :D


Oh, I spend way too much time writing...
It is embarrasing.

And it is not just the writing. I have spent most of the last six years to discuss, try out and put together that what filled the post above.

I should be in my smithy doing some honest work instead!
:blush: :eek:
Peter Johnsson wrote:


Try this out:
Grasp the grip of the sword and hold it point upwards. Tap with the heel of your hand untill you find the node of the blade. You will notice how the whole blade becomes stiff and vibrates less as you tap in the spot where the node is. From a wobbly flexible blade it suddenly becomes more like a stiff plank.


It works!?!?!? Using my AT "Lady Carmen" which is VERY flexible/wobbly, if I smack the blade at the blade node (while holding the grip) the blade is stiff as a plank but if I hit the blade above or below the node it vibrates :eek: The same is true for my NG Baron (except that it is much stiffer to start with)

Apparently Peter is on to something...Who would have guessed? ;)

Alexi

P.S. Thanks for the detailed post, Peter. I am sure glad that you type so much, as it cleared a lot of misunderstanding and confusion that I had regarding the COP and nodes (I have read million times that it is the same thing).
This is a good discussion, folks, and I'd like to especially thank Peter Johnsson for additions. This topic has enough value to warrant making it a spotlight topic.
Nathan Robinson wrote:
This is a good discussion, folks, and I'd like to especially thank Peter Johnsson for additions. This topic has enough value to warrant making it a spotlight topic.


Yay! My stupid question pays off!
I have a couple of pics of testcutting from Peters lecture during Visby medieval week 2003.
Here they are if I can figure out how to attach them :)


 Attachment: 48.23 KB
Peter is cutting with his Solingen (I think) here. [ Download ]

 Attachment: 53.34 KB
Here's the cutting target Peter described. This one's about the thickness of my thigh as you can see. [ Download ]
In reply to the original question, I'd like to point out that I had similar results on 2L bottles with my First-Gen Hastings; no matter how carefully I lined up the swing, the sword just wouldn't do more than deeply incise the bottle, to the point that it leaked at a few spots. However, I consistantly cut through every bottle I used my atrim against.

Unfortunately, the atrim beat the Hastings against other light targets, like pool noodles and the like. One thing it did do great against was the heavier targets, but I wasn't exactly enthralled with having to repolish it every time I went out cutting, so I sold it.

Now, all of that said, I have to agree that swords aren't meant to be bottle-killers...however, when all you have is bottles, it's nice to have something to cut them...which is partially why I sold the Hastings, along with it being too nicely finished for me to use. My Atrim, on the other hand, never quite had the same level of polish, so it patinated much more gracefully.
Felix Thieme wrote:
In reply to the original question, I'd like to point out that I had similar results on 2L bottles with my First-Gen Hastings; no matter how carefully I lined up the swing, the sword just wouldn't do more than deeply incise the bottle, to the point that it leaked at a few spots. However, I consistantly cut through every bottle I used my atrim against.

Unfortunately, the atrim beat the Hastings against other light targets, like pool noodles and the like. One thing it did do great against was the heavier targets, but I wasn't exactly enthralled with having to repolish it every time I went out cutting, so I sold it.

Now, all of that said, I have to agree that swords aren't meant to be bottle-killers...however, when all you have is bottles, it's nice to have something to cut them...which is partially why I sold the Hastings, along with it being too nicely finished for me to use. My Atrim, on the other hand, never quite had the same level of polish, so it patinated much more gracefully.


Just as a final addendum to this. I did some cutting with my Acre on cardboard mailing tubes, pumpkins, gourds, and melons. None of these I realize are actual representations of people, but I just wanted to say that the sword did an excellent job as long as I myself was doing an excellent job and that when I messed up it messed up. In short, it did everything I could have wanted or expected it to do. I just wanted to add this on because I felt like maybe I gave the impression that I thought the sword was "disappointing" or had serious flaws in the realm of cutting or something and I absolutely don't believe that to be true.
cutting medium
What about a strip of garden hose for a CHEAP substitute for living bone???
I use water filled gallon and half gallon milk jugs (cheap and fun). I've known people to use soaked newspapers and soaked newpapers wrapped around dowel rods or various sizes.
Wow, what an informative topic, thank you everybody. The only sword that I own is an antique sword Bayonet, most likely English. So I don't use it for cutting. What I do use is a Butcher's Cleaver that I picked up at an Antique store a few towns over. It's a downright lovely little beast and easily the best cutting tool that I have ever used, it's only 1 ft - 2 inches in length with an 8 inch blade but I've used it to cut trees wider then the blade and it can cut green lengths of wood over an inch in diameter with a single whack.
Anyway, I'm thinking that it would be appropriate to use a small green sapling length as simulated bone with newspaper wrapped around it. I'll try it out myself for fun once I get some newspapers but my Butcher's Cleaver is a very different kind of device then a sword, it's edge geometry and thickness really make it closer in nature to an ax.
Would such a target work well with a sword?
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