Sliding weights

ariel · 2nd July 2005, 10:59 AM

I remember years ago seeing a Chinese throwing knife that always hit the target with a point and got imbedded quite deeply. Apparantly the secret was a hole drilled within the entire blade along the whole length and filled with mercury. It moved freely in this channel and changed the center of gravity. Was very impressive.
I guess, the same principle as discussed here.

Jens Nordlunde · 2nd July 2005, 03:17 PM

Montino, you may be right, we will hopefully know later, but I agree with you that a heavy weight getting stuck at the tip could be fatal.

Ariel, an interesting mail about the use of mercury in the blade, I can imagine that the result have been impressive.

Jens

Mare Rosu · 2nd July 2005, 08:56 PM

Jens
You are at it again, from magnetic blades to now sliding weights.
Are you sure you moved to Switzerland and was not run off, to hide/escape?

Anyway the idea of sliding weights is a good one, while I have little to add to this subject I do think a distance related subject might be of interest to you and others and that is; Atlatls and banner stones used with them. I have found these banner stones in years past and this is just two web sites on their use. http://donsmaps.com/atlatl.html and http://www.primitive.org/atlstealth.htm.
To me a very interesting subject you have started Mr. Jens

Jens Nordlunde · 3rd July 2005, 01:38 PM

Interesting subject you raise Gene. You are right, this is about giving the weapons more dynamic power, and the links you give, show that this has been very important for thousands of years. This shows, that people in ancient times did know a lot about dynamics, although they did not know the formulas. When throwing a javelin or a light spear, it is important that you ‘arm’ is long, and here the Atlatl helped a lot, as the longer the ‘arm’ the more power you could put behind the throw. Interesting also to see that they adapted the length of the Atlatl to the surroundings, but what I find really intriguing is the use of Banner Stones, as I did not know such stones were used. I wonder how they figured out that the use of Banner Stones would make the use of the Atlatl more silent.

fearn · 3rd July 2005, 03:03 PM

Hi Jens,

This is getting a bit off subject, but I was partially thinking of atlatls when I was talking about weights absorbing shock in a sword.

The other source of inspiration was a dha-style sword I made out of a machete. I very quickly learned that there were only two good handholds on the long handle: at the end, and about 1/4 of the length from pommel to tip. This was because the sword flexed on impact, and holding it at other points was a recipe for getting a very sore hand (the best handholds were at the nodes: end, 1/4, 1/2). Personally, I think that there are a lot of hidden shock-minimizers in well-designed dhas and other long-handled blades. Otherwise, they wouldn't be worth swinging.

There's no reason that a moving weight on a blade couldn't serve a similar shock-absorbing function, but that's another design question entirely.

Personally, I'm surprised that the atlatl people weren't talking about tuning their dart and thrower systems to make the things accurate. After all, if the dart flexes the wrong way, it's not going to hit whatever the person was aiming at.

Fearn

Jim McDougall · 3rd July 2005, 03:31 PM

Outstanding discussion everybody!!!! It is extremely fascinating to read the well explained and supported observations here concerning the feasability of these weapons features. While edged weapons were in themselves primarily simple in thier dynamics, it is amazing how very complex their actual use and construction became. While the sliding weight feature discussed here remains purely conjecture found in literature thus far, many other interesting features are well established in developed examples, such as the thumb rings brought up on a concurrent thread and both hilt and blade shapes and construction.

It would appear that the sliding weight feature remains a figment of literary imagination as no existing examples have been seen, and such features are not mentioned in contemporary narratives or material describing edged weapons.

The mercury filled channel blades, while early examples seem to remain somewhat in question, the concept seems to have been applied in some latter examples of weapons, with this likely to be in response to the earlier tales of such weapons. An illustration of this occurs in at least one 'Bowie' knife produced in the 1860's with a hollow channelled blade containing mercury. Whether it was ever used is not described, however by its appearance (published in "The Bowie Knife", Norm Flayderman) it seems an extremely clumsy weapon.

As this excellent discussion continues, I remain hopeful that in some hidden corner of some archives or museum we will find evidence of the sliding weight on some long forgotten sword. I'm confident that if such a sword can be found it will be by the members and readers here!!

Meanwhile, the comprehension of physics and dynamics has always eluded me, but you guys make it understandable!!! Thank you so much!!

All the best,
Jim

Jens Nordlunde · 3rd July 2005, 04:37 PM

Hi Fearn,

I don’t think you are off subject, or if you are, it is only a fraction, as the whole subject is about dynamic power/shock-minimizing and stuff like that, so the way I see it, you are on track. I find, what you write about your dha-style sword most interesting. I have always been wondering about the long hilt, but I was wondering about it – you did something about it and tried it out, so now you have a knowledge, which I fail to have. Thank you for sharing.
In the start I did not think about the shock-absorption made by the weights, but I guess you are right, this could be an extra plus to such a construction. The hand would not have to take the whole of the blow – it would be divided – but with how much to the weight and how much to the hand?
I am sure, that those using an atlatl centuries ago, had everything tuned in, so that they were sure to hit the target – they could not afford otherwise.

Hi Jim,

You are right; the discussion gets more and more interesting, as we get more and more implements into the discussion. What I think we can agree on is, that sword smiths in the old times must have had a very good idea about dynamics and shock-absorption – more than we normally think of, when we buy a sword for our collection.

Jens

2nd July 2005, 08:56 PM	#3
Mare Rosu Deceased Join Date: Dec 2004 Location: USA, DEEP SOUTH, GEORGIA, Y'all hear? Posts: 121	Banner Stone Jens You are at it again, from magnetic blades to now sliding weights. Are you sure you moved to Switzerland and was not run off, to hide/escape? Anyway the idea of sliding weights is a good one, while I have little to add to this subject I do think a distance related subject might be of interest to you and others and that is; Atlatls and banner stones used with them. I have found these banner stones in years past and this is just two web sites on their use. http://donsmaps.com/atlatl.html and http://www.primitive.org/atlstealth.htm. To me a very interesting subject you have started Mr. Jens

2nd July 2005, 10:59 AM	#1
ariel Member Join Date: Dec 2004 Location: Ann Arbor, MI Posts: 5,503	I remember years ago seeing a Chinese throwing knife that always hit the target with a point and got imbedded quite deeply. Apparantly the secret was a hole drilled within the entire blade along the whole length and filled with mercury. It moved freely in this channel and changed the center of gravity. Was very impressive. I guess, the same principle as discussed here.

2nd July 2005, 03:17 PM	#2
Jens Nordlunde Member Join Date: Dec 2004 Location: Europe Posts: 2,718	Montino, you may be right, we will hopefully know later, but I agree with you that a heavy weight getting stuck at the tip could be fatal. Ariel, an interesting mail about the use of mercury in the blade, I can imagine that the result have been impressive. Jens

3rd July 2005, 01:38 PM	#4
Jens Nordlunde Member Join Date: Dec 2004 Location: Europe Posts: 2,718	Interesting subject you raise Gene. You are right, this is about giving the weapons more dynamic power, and the links you give, show that this has been very important for thousands of years. This shows, that people in ancient times did know a lot about dynamics, although they did not know the formulas. When throwing a javelin or a light spear, it is important that you ‘arm’ is long, and here the Atlatl helped a lot, as the longer the ‘arm’ the more power you could put behind the throw. Interesting also to see that they adapted the length of the Atlatl to the surroundings, but what I find really intriguing is the use of Banner Stones, as I did not know such stones were used. I wonder how they figured out that the use of Banner Stones would make the use of the Atlatl more silent.

3rd July 2005, 03:03 PM	#5
fearn Member Join Date: Dec 2004 Posts: 1,247	Hi Jens, This is getting a bit off subject, but I was partially thinking of atlatls when I was talking about weights absorbing shock in a sword. The other source of inspiration was a dha-style sword I made out of a machete. I very quickly learned that there were only two good handholds on the long handle: at the end, and about 1/4 of the length from pommel to tip. This was because the sword flexed on impact, and holding it at other points was a recipe for getting a very sore hand (the best handholds were at the nodes: end, 1/4, 1/2). Personally, I think that there are a lot of hidden shock-minimizers in well-designed dhas and other long-handled blades. Otherwise, they wouldn't be worth swinging. There's no reason that a moving weight on a blade couldn't serve a similar shock-absorbing function, but that's another design question entirely. Personally, I'm surprised that the atlatl people weren't talking about tuning their dart and thrower systems to make the things accurate. After all, if the dart flexes the wrong way, it's not going to hit whatever the person was aiming at. Fearn

3rd July 2005, 03:31 PM	#6
Jim McDougall Arms Historian Join Date: Dec 2004 Location: Route 66 Posts: 10,281	Outstanding discussion everybody!!!! It is extremely fascinating to read the well explained and supported observations here concerning the feasability of these weapons features. While edged weapons were in themselves primarily simple in thier dynamics, it is amazing how very complex their actual use and construction became. While the sliding weight feature discussed here remains purely conjecture found in literature thus far, many other interesting features are well established in developed examples, such as the thumb rings brought up on a concurrent thread and both hilt and blade shapes and construction. It would appear that the sliding weight feature remains a figment of literary imagination as no existing examples have been seen, and such features are not mentioned in contemporary narratives or material describing edged weapons. The mercury filled channel blades, while early examples seem to remain somewhat in question, the concept seems to have been applied in some latter examples of weapons, with this likely to be in response to the earlier tales of such weapons. An illustration of this occurs in at least one 'Bowie' knife produced in the 1860's with a hollow channelled blade containing mercury. Whether it was ever used is not described, however by its appearance (published in "The Bowie Knife", Norm Flayderman) it seems an extremely clumsy weapon. As this excellent discussion continues, I remain hopeful that in some hidden corner of some archives or museum we will find evidence of the sliding weight on some long forgotten sword. I'm confident that if such a sword can be found it will be by the members and readers here!! Meanwhile, the comprehension of physics and dynamics has always eluded me, but you guys make it understandable!!! Thank you so much!! All the best, Jim

3rd July 2005, 04:37 PM	#7
Jens Nordlunde Member Join Date: Dec 2004 Location: Europe Posts: 2,718	Hi Fearn, I don’t think you are off subject, or if you are, it is only a fraction, as the whole subject is about dynamic power/shock-minimizing and stuff like that, so the way I see it, you are on track. I find, what you write about your dha-style sword most interesting. I have always been wondering about the long hilt, but I was wondering about it – you did something about it and tried it out, so now you have a knowledge, which I fail to have. Thank you for sharing. In the start I did not think about the shock-absorption made by the weights, but I guess you are right, this could be an extra plus to such a construction. The hand would not have to take the whole of the blow – it would be divided – but with how much to the weight and how much to the hand? I am sure, that those using an atlatl centuries ago, had everything tuned in, so that they were sure to hit the target – they could not afford otherwise. Hi Jim, You are right; the discussion gets more and more interesting, as we get more and more implements into the discussion. What I think we can agree on is, that sword smiths in the old times must have had a very good idea about dynamics and shock-absorption – more than we normally think of, when we buy a sword for our collection. Jens