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James Aldrich




Location: Green Bay WI
Joined: 21 Aug 2003

Posts: 112

PostPosted: Tue 30 Nov, 2004 9:49 pm    Post subject: PKS failure         Quote

I was helping my grandson with a school presentation when I attempted to demonstrate the flexibility of this Practical Knightly Sword. With the grip in one hand and the tip in the other, I had just begun to flex when . . . not a sound, felt like breaking a fresh cookie. Glad I never actually struck anything with this thing.

Post mortem revealed the tang to be the exact width and thickness of the fuller. Holy tort reform, Batman; I've got three more of these bombs waiting to go off.
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James Aldrich




Location: Green Bay WI
Joined: 21 Aug 2003

Posts: 112

PostPosted: Tue 30 Nov, 2004 9:50 pm    Post subject:         Quote

Oops. Here's the pre-post mortem.
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Anders Lindkvist




Location: Sweden
Joined: 11 Aug 2004

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PostPosted: Wed 01 Dec, 2004 3:09 am    Post subject: Gaaahhh.....         Quote

mmmkay, that is the CAS-iberia practical sword I guess with just another grip.

I own one myself and I have been fighting alot with that sword i reenactmentfighing. When I saw this I begun to feel a little bit nervous....I hope that won´t happen to me. That is really scary... :\

/Anders

My blog about history, handcrafts and reenactment.
http://kurage.wordpress.com
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James Aldrich




Location: Green Bay WI
Joined: 21 Aug 2003

Posts: 112

PostPosted: Wed 01 Dec, 2004 5:31 am    Post subject:         Quote

Anders,

The "over-wrap" was added by the previous owner. He blued the fuller as well. I have three more of these swords, mainly so I can let students handle them. I'm glad Iwas handling this one when it failed.

I believe this model has had three incarnations. I'm hoping this one was an early version. Certainly my remaining three have a different appearance in the peening of the tang over the pommel. Nevertheless I will now be more vigilant about howthey are handled.

JSA
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Scott Byler




Location: New Mexico
Joined: 20 Aug 2003

Posts: 209

PostPosted: Wed 01 Dec, 2004 5:40 am    Post subject:         Quote

Doesn't look like they radiused the shoulder much either. I wonder if the tang and shoulder junction was hardened... I've piddled a bit with thin tangs on experiments and find that they will bend but not snap if that area isn't hardened in the heat treat process. If it was hardened, which is an accepted way of doing tangs as well, it would be most prudent to make darn sure that the area was drawn back to a nice tough range. Ofcourse, all that is an aside to the fact that the fuller looks to have been a great weakness in the geometry of the tang.
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Anders Lindkvist




Location: Sweden
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PostPosted: Wed 01 Dec, 2004 6:52 am    Post subject: hmmm         Quote

Well, my version is about 1,5 years old and the tang is peened over the pommel on this one. But the pommel is a little bit loose and I had to thighten it a couple of time.

The tang of the broken sword was perhaps overhardened and such thin tang could then easily break. How does the break area looks in close-up? I was thinking of the size of the iron-cristalls.

/Anders

My blog about history, handcrafts and reenactment.
http://kurage.wordpress.com
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Peter Johnsson
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PostPosted: Wed 01 Dec, 2004 7:34 am    Post subject:         Quote

Two comments:

First (and this is important):
Avoid the temptation to keep demonstrating the flexibility of a blade. That goes for any blade.
I know this is hard to resist sometimes, but it is good to un-learn that bad habit of always flexing the blade time and time again.

Exept from fencing epees blades are *not* made to be flexed over and over. They are designed to survive it. It is not their intended primary function.

The flexibility that there is is meant for shock absorbing. In use a blade won´t flex as far as you make it do when doing flex demos. There should be a wide margin of safety in any sound design, but it is good not to stress this safety margin by making the blade tired.
After a number of flexes (many thousands or a few hundred depending on design and quality) the sword could in the end fail. Sad thing but a real possibility. It can also be potentially dangerous: if the blade is stressed by much bending it can fail during sparring. Not only embarrasing, but also potantially very dangerous.
When you *do* demonstrate flexibility, NEVER EVER force the blade into a bend by grasping the point and hilt.
I cannot overstress this. DO NOT force the blade into a curve.
Instead put the point on the floor and press down on the hilt. This way you let the blade follow its own stress curve.
If you grasp the point and hilt you will invariable overstress some part of the blade. NOT a good idea.
Square corners at the base of the tang can be an issue, but not as important as you might think. Many originals have square cut corners at the base of the tang, but as a rule originals have much healthier dimensions than most modern replics. This is not just a matter of absolute dimensions but equally important, how the thickness of the meeting

Secondly:
Do not expect a low range priced sword to perform with the same margin of safety as a higher priced sword.
You always get what you pay for. It is a sad rule but more often true than not.
In this case the fuller was obviously ground too wide as it grew into the tang. This is a cardinal flaw in the design. Sad to see. A feature like this will create a weak spot with high risk of failiure.

In this case it is pretty clear the sword failed first of all from a design flaw. The blade di not break. It was a weak spot in the meeting between blade and tang that manifested itself. The steel might have been overheated, but tha main thing is that the fuller was cut too wide as it entered the tang. This is no problem if you keep the tang in healthy dimensions and shape the fuller accordingly. In this case the tang seems to be too narrow and the fuller is obviously too wide and too deep as it enters the tang. No good.
This might be a odd specimen and the rest of the line perfectly fine. I don´t know...

As a maker and designer I feel reluctant to add a comment on a thread about the product of another maker. Plese excuse me if you think I´m overstepping by posting this. I really do not mean this as an attack on this specific product or maker. It is just a good example of how seemigly simple details in the design can be of paramount importance: for example how the end of the fuller is shaped in the tang. If done right the solution is a good one, If not it makes for high risk of failiure.

Flexing and resilience is an issue that relates to all swords in all price ranges and all levels of quality.
Whenever meeting customers I make a point of showing how to test for flexibility and also to stress the fact that it is a bad idea to keep flexing your sword over and over again.
There is no cause for concern if this happens once in a while, but I sometimes see people who have a fixation on flexing their blades. That is just a bad habit. Please stop doing that, at once :-)
To show that a swords flexes does not say much of the quality in the first place. Some blades are designed to be stiff and wont flex much at all. If such a blade is forced to flex it will be even more stressed than a wide flat blade that is made to stand more flexing.
A maker that is concerned with quality should do stress tests on his own blades: striking, cutting and flexing to a certain degree. After this is done, no further testing is needed.
If you need to show the flexibility of a blade: put the point towards the ground and press on the hilt. Do not flex too much, just to show the blade is flexible. If you really need to, that is...



:D :cool:
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Kirk Lee Spencer




Location: Texas
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PostPosted: Wed 01 Dec, 2004 8:31 am    Post subject:         Quote

Peter Johnsson wrote:

The steel might have been overheated, but tha main thing is that the fuller was cut too wide as it entered the tang. This is no problem if you keep the tang in healthy dimensions and shape the fuller accordingly. In this case the tang seems to be too narrow and the fuller is obviously too wide and too deep as it enters the tang. No good...



This is what I thought when I first saw the picture... I have a William Marshall from the same maker with the same blade design and one thing that stands out how deep the fuller is. So... If you have such a deep fuller on both sides of the blade and you carry it into the tang and the tang is not wide enough to incorporate the thickened ridges on either side of the fuller then, as I see it, that tang is only attached to that blade by a tiny amount of metal... If we could see a close up of the cross-section where it broke on the blade I suspect that we would see that only two thin slivers of metal on the upsweep of the fuller is all that held the hilt of this sword on. If so it is a wonder that it did not break the first time it was flexed.

James,
Thanks so much for taking the time to inform us... I need to take down my blade and see if it is the same.... I certainly will not be swinging it around.

ks

Two swords
Lit in Eden’s flame
One of iron and one of ink
To place within a bloody hand
One of God or one of man
Our souls to one of
Two eternities
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Scott Byler




Location: New Mexico
Joined: 20 Aug 2003

Posts: 209

PostPosted: Wed 01 Dec, 2004 8:55 am    Post subject:         Quote

I think that the caution against flexing a lot is well advised, and I believe Tinker and Kevin Cashen have both mentioned (and probably others, as well, when I wasn't looking... :D ) the fatigue issue before as well. Whether many folks are watching and listening, is the question. One hopes so...
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Paul Craddock




Location: England
Joined: 01 Dec 2004

Posts: 3

PostPosted: Wed 01 Dec, 2004 10:06 am    Post subject:         Quote

Hi, just joined this group.
I expect this is probably a mark 1 or 2 as they were very disappointing
('cause they kept breaking!) The Mk1 was too soft (about Rockwell 30 and the
tang too thin. Mk2 better hardness (about R45) but still too thin. I sent
loads of bits back so he got the hint and I have had no returns of the Mk3
which is MUCH thicker. You can tell Mk1/2 from Mk3 easily. The cross guard
and scabbard fittings on Mk1/2 were chrome (very shiny). Mk3 is a dull steel
colour.
If anyone has any further queries or concerns please contact me.

Druid

Never put off until tomorrow what you can do today because if you like it you can do it again tomorrow!
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Sean Flynt




Location: Birmingham, Alabama
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PostPosted: Wed 01 Dec, 2004 10:51 am    Post subject:         Quote

But now you have a very interesting project blade! Any plans for it?
-Sean

Author of the Little Hammer novel

https://www.amazon.com/Little-Hammer-Sean-Flynt/dp/B08XN7HZ82/ref=sr_1_1?dchild=1&keywords=little+hammer+book&qid=1627482034&sr=8-1
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Greyson Brown




Location: Windsor, Colorado
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PostPosted: Wed 01 Dec, 2004 2:20 pm    Post subject:         Quote

I had a sword that suffered from the same design flaw. I am guilty of having flexed it a couple of times, and it had also been dropped on a few occasions. I have discovered that some people are very eager to hold a sword, but the moment it touches their hand, they get nervous and drop it. I don't understand that phenomenon, but it happened to this sword. During this last year, while I was away, my cousin and her husband asked to borrow some swords for "decoration" at a church event. I generally trust my extended family, and have loaned them swords in the past, so I consented. Apparently, my aunt (who I don't trust with a plastic spoon) got involved at the last minute, and "decoration" took on a new meaning. Apparently, in mid-swing (at this moment in the recounting, my eyes got wide, and I said "explain yourself more fully please") the blade broke off in exactly the same spot as the one James showed, and almost hit some one. Further interrogation revealed that my sword had become a prop for a dinner theatre in addition to the church event. I was not overly worried about the loss of the sword, as it had been very inexpensive ($80, I think), but I was rather upset about the careless use of my swords, and the potential injury to innocent bystanders. Inspection of the sword while I was home on R&R showed that the tang was too narrow (only about 3/8 to 1/2 inch wide), and too thin (about 1/8 inch). The fuller once again was too wide, and I noticed a rather large grain structure on mine.

I tried forging a new tang on the shoulder end of the blade, but the blade split down the center of the fuller. That further indicates to me that the steel had been overheated at some point. So, James, you might have to take a different approach to using yours as a project blade. The fuller on this particular blade would probably not been a problem, but design and structural problems took their toll.

This event has made me wary of any blade where the fuller extends onto the tang, but I think that is unfounded. There are too many historical examples of it for that one feature to be a true problem. Instead, proper proportions and a well-though out design need to be employed to create the sturdiest, safest sword possible.

-Grey

Wishing you no more catastrophic disassemblies.

"So long as I can keep the path of honor I am well content."
-Sir Arthur Conan Doyle, The White Company
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Steve Grisetti




Location: Washington DC metro area, USA
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PostPosted: Wed 01 Dec, 2004 6:31 pm    Post subject:         Quote

Wow. "you get what you pay for" takes on a whole new meaning. As does "penny-wise and pound-foolish" (the penny wise being the purchase, and the pound foolish being the potential legal consequences)
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Anders Lindkvist




Location: Sweden
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PostPosted: Thu 02 Dec, 2004 1:52 am    Post subject:         Quote

Paul Craddock wrote:
Hi, just joined this group.
I expect this is probably a mark 1 or 2 as they were very disappointing
('cause they kept breaking!) The Mk1 was too soft (about Rockwell 30 and the
tang too thin. Mk2 better hardness (about R45) but still too thin. I sent
loads of bits back so he got the hint and I have had no returns of the Mk3
which is MUCH thicker. You can tell Mk1/2 from Mk3 easily. The cross guard
and scabbard fittings on Mk1/2 were chrome (very shiny). Mk3 is a dull steel
colour.
If anyone has any further queries or concerns please contact me.

Druid


I´m hoping that my sword is a Mk3 then. When did the last version came out?

/Anders

My blog about history, handcrafts and reenactment.
http://kurage.wordpress.com
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Sean Flynt




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PostPosted: Thu 02 Dec, 2004 7:29 am    Post subject:         Quote

You might be able to grind a new tang and make something like the Windlass Coustille.
-Sean

Author of the Little Hammer novel

https://www.amazon.com/Little-Hammer-Sean-Flynt/dp/B08XN7HZ82/ref=sr_1_1?dchild=1&keywords=little+hammer+book&qid=1627482034&sr=8-1
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Paul Craddock




Location: England
Joined: 01 Dec 2004

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PostPosted: Thu 02 Dec, 2004 10:08 am    Post subject:         Quote

Mk3 has been out about 12 months.

Druid

Never put off until tomorrow what you can do today because if you like it you can do it again tomorrow!
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Jason Dingledine




Location: Aurora, Ohio
Joined: 18 Aug 2003

Posts: 219

PostPosted: Thu 02 Dec, 2004 3:33 pm    Post subject:         Quote

Hey Everybody,

One thing to keep in mind with any mishaps like this (or problems with any items of any kind) is to take into consideration what the production costs might have been. It would be easy to just say, "You get what you pay for", but really looking at it can be scary.

Not all business operate this way, but the traditional way business mark-ups happen is that every time a product changes hands, the price doubles. This increase is to provide for expenses and profit margins for those that are adding to the product in some way. This value adding can be either part of the actual product or a service provided. If you start with the retail price of any item and break it down, it could possbily look something like this:

$200----Retail price paid by consumer from a retailer: retailer cost--$100

$100----Wholesale cost to retailer from Clearing House Agent (in the case of non-domestic imports): Clearing House Cost-- $50

$50----Clearing House cost from Overseas Manufacturer: Manufacturer cost-- $25

This means that the cost to produce that item (materials, labor, overhead, shipping) totals $25.

The above model is very rarely seen in this particular industry, sometimes it is drasticly above this and at time, drasticly less. This is the second sword from the "Practical" in the last month that I have seen posts about blade failures. There is another discussion happening on Bugei's forum http://www.swordforumbugei.com/phpBB2/viewtop...highlight= in which Keith has made a few very wise comments.

I don't mean to dissuade anybody from buying these swords, but at the price they are sold for quality becomes suspect. It is not always what you can see as well, but often what you can't see.

This is also a case for attempting to buy directly from the manufacturer, or as close of possible. The fewer times an item changes hands (at a given retail price) the higher one can expect the quality to be. In theory (not practice unfortunately) for every middle man that is removed from the equation, the product quality theorectically doubles.

This may not always be true be as for some companies that do only a very little wholesaling, the wholsale price may only be 20-50% over cost, in order for the retailer to be able to remain competetive.

Jason Dingledine
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James Aldrich




Location: Green Bay WI
Joined: 21 Aug 2003

Posts: 112

PostPosted: Thu 02 Dec, 2004 7:39 pm    Post subject:         Quote

Thanks to Peter for the well-deserved chastisement and solid advice. Thanks to all for the information and insightful questions. It's been a learning experience.

As far as I can recall that is the first time I attempted to flex that blade, or any other blade, in that manner. I was an epeeist in my university days . . . God forbid it's an unconscious mannersim :) A "senior moment," I hope.

I have been unable to produce a decent photograph of the fracture surfaces. My camera won't focus close enough for detail and any light source sufficient to illuminate the subject results in overwhelming glare.

To my eye, the surfaces are rough, very fine-grained, light grey with a touch of glitter. At one extreme of the break there is a 2-3mm dark spot on both pieces. That's the best descrption I can give.

JSA
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James Aldrich




Location: Green Bay WI
Joined: 21 Aug 2003

Posts: 112

PostPosted: Thu 02 Dec, 2004 7:42 pm    Post subject:         Quote

Sean Flynt wrote:
You might be able to grind a new tang and make something like the Windlass Coustille.


Alas, I have neither the equipment, the skills, or the time to accomplish anything with the blade. I'll probably pass it on to a friend who can work with it.

JSA
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Russ Ellis
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PostPosted: Fri 03 Dec, 2004 5:50 am    Post subject:         Quote

I've been following this thread with interest due to recent events with the grosse messer that I once owned. Some of the similarities are rather interesting as far as the cheap price of the sword involved and in particular the "dark" places at the break that James describes. Anyone know what those "dark" places are likely to be? Apparently the grosse messer also showed such a discoloration at the break.
TRITONWORKS Custom Scabbards
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