Info Favorites Register Log in
myArmoury.com Discussion Forums

Forum index Memberlist Usergroups Spotlight Topics Search
Forum Index > Off-topic Talk > bent blade, can it be made straight? Reply to topic
This is a standard topic  
Author Message
Mike West




Location: North Carolina
Joined: 06 Dec 2003
Likes: 4 pages

Posts: 84

PostPosted: Wed 17 Sep, 2008 1:41 pm    Post subject: bent blade, can it be made straight?         Reply with quote

Hello,

I recently purchased a old MRL Del Tin (a 5143) from ebay. The sword arrived with a broken box, that had been re-taped. The sword inside was in nice condition, other than a bent blade! The upper 3rd of the blade is about 5 degrees off, making that part close to an 85/86 degree angle.

Could this be repaired to make the blade straight again? If so, who could I contact to do it properly?

Thank you.
View user's profile Send private message
Gabriel Lebec
myArmoury Team


myArmoury Team

Location: NY, NY
Joined: 02 Oct 2003
Reading list: 32 books

Posts: 419

PostPosted: Wed 17 Sep, 2008 3:14 pm    Post subject:         Reply with quote

I'm heading out, but briefly: I know togishi (Japanese sword polishers) use two wooden blocks with notches in them to lever bent blades back into shape.

Scientifically speaking there is always a permanent (if, one hopes, negligible) amount of internal damage to steel once the blade has taken a set like this, even if it is then bent back. In fact, it is theoretically impossible to actually bend it back to its 100% original form! But macroscopically you can get it close enough that you won't know the difference, or at least care. Happy

Off topic: hey, it's better than aluminum. According to my (aerospace engineering student) brother, once aluminum metal is formed, EVERY stress applied to it creates internal damage. This is one reason why all airplanes have ultimately limited lifespans. Don't worry, they are retired long before aluminum stress in the wing becomes a real worry. Wink

More worryingly, I would like to hear whether western swords like this are supposed to take a set. I was under the impression that they should be fairly "springy" and require significant deviation to obtain an actual set, otherwise their heat treatment may be suspect. But I don't actually know the details, so someone please educate me.

"The most beautiful experience we can have is the mysterious. It is the fundamental emotion that stands at the cradle of true art and true science." - Albert Einstein
________
View user's profile Send private message
Michael Edelson




Location: New York
Joined: 14 Sep 2005

Spotlight topics: 2
Posts: 1,032

PostPosted: Wed 17 Sep, 2008 4:01 pm    Post subject:         Reply with quote

Yes it can, good as new. We actually had a good discussion a while back about how doing so doesn't really damage the sword all that much, up to a point (depending on steel, etc.).

Try putting the bent part over your knee with the bent end up and grab it (with gloves) on either end of the bend and use quick jerky movements, bending it in the opposite direction of bend. You don't need to bend it much either. Either the sword will want to be straight and will straighten, or it is soft and will straighten, or it will not, in which case you'll need some sort of jig and or heat (depending on steel type). Del Tins tend to be soft and you can probably straighten it over your knee.

I am hereby formally advising you to wear full plate or mail harness before trying this at home. To do otherwise is to risk injury. Happy

New York Historical Fencing Association
www.newyorklongsword.com

Byakkokan Dojo
http://newyorkbattodo.com/
View user's profile Send private message Visit poster's website
Justin King
Industry Professional



Location: flagstaff,arizona
Joined: 12 Apr 2004
Reading list: 20 books

Posts: 551

PostPosted: Wed 17 Sep, 2008 6:14 pm    Post subject:         Reply with quote

If you very carefully heat the blade at the bend to 400-450 degrees F. it will be much easier to straighten and you will avoid much of the stress from doing so, without exceeding the tempering range of most sword blades.
Obviously you don't want to straighten it over your knee if you are heating it.
View user's profile Send private message
Chris Fields




Location: Tampa, Fl
Joined: 03 Aug 2008

Posts: 114

PostPosted: Wed 17 Sep, 2008 8:00 pm    Post subject:         Reply with quote

I wouldn't use any heat. Only because there is no way for you measure 400 - 450 accuratly while you are trying to straiten it. You'll most likely over heat it and screw up the temper, unless you have the tools for that. Del Tin uses 6150, you'll have to over flex it slighty in the opposite direction as suggested before to get it back strait. Such a slight set shouldn't be a big deal to reset. Western swords are generally alot more springy that Japanese swords.
View user's profile Send e-mail
Mike West




Location: North Carolina
Joined: 06 Dec 2003
Likes: 4 pages

Posts: 84

PostPosted: Wed 17 Sep, 2008 8:12 pm    Post subject: Thanks.         Reply with quote

I also wondered about the heating the blade, as I have no idea how to measure the temperature of a hot sword blade.

Once I get the insurance money(hopefully), I will try to bend the blade back myself, or visit a sword cutler for help. Perhaps a machinist could help, or someone that had toools to bend metal?

Since the blade was an MRL Del Tin, it is made from the "krupp" steel they used to use. I wonder if that would affect the bending process?
View user's profile Send private message
Michael Edelson




Location: New York
Joined: 14 Sep 2005

Spotlight topics: 2
Posts: 1,032

PostPosted: Wed 17 Sep, 2008 8:53 pm    Post subject:         Reply with quote

Heat should not be used with all swords, because it depends on the steel and heat treat. Ask Angus Trim, he'd be able to tell you more. What little I know about that comes from having spoken with him.

Del Tin's, in my experience, are soft, which is good for you, because it means this sword should be easier to straighten.

New York Historical Fencing Association
www.newyorklongsword.com

Byakkokan Dojo
http://newyorkbattodo.com/
View user's profile Send private message Visit poster's website
Bruno Giordan





Joined: 28 Sep 2005

Spotlight topics: 1
Posts: 918

PostPosted: Thu 18 Sep, 2008 10:43 am    Post subject:         Reply with quote

A good blade shouldn't bend ... strange story

I would send it to a pro for disassembling, straitening and a new heat treat (ok i would do it myself but that's not your case).


By beating it back you could break or scratch it.
View user's profile Send private message
Michael Edelson




Location: New York
Joined: 14 Sep 2005

Spotlight topics: 2
Posts: 1,032

PostPosted: Thu 18 Sep, 2008 11:24 am    Post subject:         Reply with quote

Bruno Giordan wrote:
A good blade shouldn't bend ... strange story

I would send it to a pro for disassembling, straitening and a new heat treat (ok i would do it myself but that's not your case).


By beating it back you could break or scratch it.


Any blade will bend if it either flexes past its point of tolerance or experience a fast and powerful flex under pressure (that is not necessarily past its point of tolerance). The thicker the blade, the harder it is to bend. Properties of the steel can also make a sword more resistant to bending, but the more resistant a sword is to bending, by virtue of either thickness or heat treat, the more damage is done when the sword actually bends.

I have seen sword by every major (and not so major) maker take sets. It happens, and it doesn't take much. Nor has any sword, in my experience, ever been the worse for wear after a set.

New York Historical Fencing Association
www.newyorklongsword.com

Byakkokan Dojo
http://newyorkbattodo.com/
View user's profile Send private message Visit poster's website
Gabriel Lebec
myArmoury Team


myArmoury Team

Location: NY, NY
Joined: 02 Oct 2003
Reading list: 32 books

Posts: 419

PostPosted: Thu 18 Sep, 2008 1:41 pm    Post subject:         Reply with quote

Michael Edelson wrote:
...or experience a fast and powerful flex under pressure (that is not necessarily past its point of tolerance).

Interesting - I've not heard this. Do you know the theory behind it? My curiosity is piqued.

"The most beautiful experience we can have is the mysterious. It is the fundamental emotion that stands at the cradle of true art and true science." - Albert Einstein
________
View user's profile Send private message
Michael Edelson




Location: New York
Joined: 14 Sep 2005

Spotlight topics: 2
Posts: 1,032

PostPosted: Thu 18 Sep, 2008 3:19 pm    Post subject:         Reply with quote

Gabriel Lebec wrote:
Michael Edelson wrote:
...or experience a fast and powerful flex under pressure (that is not necessarily past its point of tolerance).

Interesting - I've not heard this. Do you know the theory behind it? My curiosity is piqued.


No, sorry, I don't. We've bent swordd during mat cutting (I keep piling on more and more mats until I run out of mats or something bends! Happy ) and analyzed the video of the cut, frame by frame.

I noticed that in each case, the degree of flex was not more than the sword could handle in a static flex test yet the sword took a set. Also, when straightening these swords (those that wanted to be straightened), I didn't flex it all that much in the other direction...in fact not much at all...but I did it quickly and violently, and that did it. If I flex to the same degree or even more, but do it slowly and gently, nothing happens, the sword remains set.

I remember one particular sword that took a slight set after striking a cutting stand, but the video didn't show much flex at all. This was(is) a good sword by one of the big 3 that worked for a long time both before and after that set and had no problems at all.

New York Historical Fencing Association
www.newyorklongsword.com

Byakkokan Dojo
http://newyorkbattodo.com/
View user's profile Send private message Visit poster's website
R D Moore




Location: Portland Oregon
Joined: 09 Jun 2007
Likes: 7 pages
Reading list: 11 books

Spotlight topics: 1
Posts: 425

PostPosted: Thu 18 Sep, 2008 4:48 pm    Post subject:         Reply with quote

Sorry to come in so late with this, but here is one of the threads dealing with straightening bent blades. http://www.myArmoury.com/talk/viewtopic.php?t=14117
I wont hesitate to straighten any of mine now after reading it. I would't heat the blade, though. I'd send it to someone who knows what they're doing.
View user's profile Send private message Send e-mail
Bruno Giordan





Joined: 28 Sep 2005

Spotlight topics: 1
Posts: 918

PostPosted: Fri 19 Sep, 2008 1:14 am    Post subject:         Reply with quote

Michael Edelson wrote:
Bruno Giordan wrote:
A good blade shouldn't bend ... strange story

I would send it to a pro for disassembling, straitening and a new heat treat (ok i would do it myself but that's not your case).


By beating it back you could break or scratch it.


Any blade will bend if it either flexes past its point of tolerance or experience a fast and powerful flex under pressure (that is not necessarily past its point of tolerance). The thicker the blade, the harder it is to bend. Properties of the steel can also make a sword more resistant to bending, but the more resistant a sword is to bending, by virtue of either thickness or heat treat, the more damage is done when the sword actually bends.

I have seen sword by every major (and not so major) maker take sets. It happens, and it doesn't take much. Nor has any sword, in my experience, ever been the worse for wear after a set.


I think a properly treated blade couldn't take set easily .. I have seen quite a few, handmade blades, blades beaten by trip hammer and then heat treated professionally, who wouldn't take a bend, but were springy and resilient.

Such blades were made of proper alloy (cr and Si), and were capable to break reenactment blades rather easily if opposed to the usual czech weapons we have here.

Deltin states clearly on is website that he is taking no responsibilities for the use of his blades, they are made with italian law in mind: most likely he makes them soft to avoid legal problems who could derive from breakage during steel stage fight, as such fight often go well beyond the stage combat level here.

On he contrary, I have tested just an albion, with a friend bending it mercilessly around his leg .. almost as if to break it.

It went back into shape without problems. Hats down to their heat treating facility and policy ...


What happens is likely that, beyond the hype, many makers think in very realistic terms, thinking of the use who could be made of their sword, which could lead to legal troubles in case of accidents.
View user's profile Send private message
Michael Edelson




Location: New York
Joined: 14 Sep 2005

Spotlight topics: 2
Posts: 1,032

PostPosted: Fri 19 Sep, 2008 9:33 am    Post subject:         Reply with quote

Bruno Giordan wrote:


I think a properly treated blade couldn't take set easily .. I have seen quite a few, handmade blades, blades beaten by trip hammer and then heat treated professionally, who wouldn't take a bend, but were springy and resilient.

Such blades were made of proper alloy (cr and Si), and were capable to break reenactment blades rather easily if opposed to the usual czech weapons we have here.

Deltin states clearly on is website that he is taking no responsibilities for the use of his blades, they are made with italian law in mind: most likely he makes them soft to avoid legal problems who could derive from breakage during steel stage fight, as such fight often go well beyond the stage combat level here.

On he contrary, I have tested just an albion, with a friend bending it mercilessly around his leg .. almost as if to break it.

It went back into shape without problems. Hats down to their heat treating facility and policy ...


What happens is likely that, beyond the hype, many makers think in very realistic terms, thinking of the use who could be made of their sword, which could lead to legal troubles in case of accidents.


Bruno,

I've been studying swordsmanship for almost 20 years now, and done a lot of cutting in that time. I've seen bent Angus Trim swords, Albion, Arms and Armor, custom hand forged, nihonto (antique) and more.

These sets do not occur in testing, they occur in cutting, when things happen. Like when someone strikes the cutting stand hard, or cuts a tripple mat and the 20lb thing falls of the stand and takes the sword with it, etc.

All of these swords have been straightened, and all of the good ones continue to serve flawlessly. Some had to be sent back to the manufacturer because they refuse to be straightened on their own, others came back to true with little effort.

Steel is steel, and there are limits to what it can take. I remember at the first Chivalric Weekend Dan Maragni gave Todd Sullivan a Norman sword prototype to test. The thing was a moster, sharp as hell and thick and heavy. We bashed it against pells, trees, whatever. The think took a beating and kept on ticking. Of course it took many sets, first in one direction, than in the other, once I whacked it into a tree and it straightened! Well, almost.

Sometimes you don't even know you bent it. One of our guys used a couple of thick gen 2s at our last cutting event. It was his first time with tatami and he was very, shall we say enthusiastic. He had no idea he bent his swords until I looked at them and said "hey, these are shaped like an S". Easily straightened, though. It appears Generation 2 swords are quite soft.

The point is, the only people who think swords should not bend are people who have never bent a sword. The first time is a horrifying experience. "Oh my god I bent it!". After a while, you realize that if you want to actually use the sword, and use it hard, it's going to bend eventually, and you are going to straighten it and then keep right on using it.

I completely understand that some people just don't want to accept the fact that their expensive beautiful swords can take a set, and without much provocation, but there it is. It's a fact.

New York Historical Fencing Association
www.newyorklongsword.com

Byakkokan Dojo
http://newyorkbattodo.com/
View user's profile Send private message Visit poster's website
Luka Borscak




Location: Croatia
Joined: 11 Jun 2007
Likes: 7 pages

Posts: 2,229

PostPosted: Fri 19 Sep, 2008 3:51 pm    Post subject:         Reply with quote

Ah, if I knew that before I returned my bent Gen2 12th century sword... I loved that sword for some reason and I was very dissapointed when it bent. I couldn't straighten it's probably because I didn't know how...
View user's profile Send private message
Michael Edelson




Location: New York
Joined: 14 Sep 2005

Spotlight topics: 2
Posts: 1,032

PostPosted: Fri 19 Sep, 2008 6:00 pm    Post subject:         Reply with quote

Luka Borscak wrote:
Ah, if I knew that before I returned my bent Gen2 12th century sword... I loved that sword for some reason and I was very dissapointed when it bent. I couldn't straighten it's probably because I didn't know how...


Wanna hear something funny?

Do you know Bill Tsafa, the tire pell guy? We he was the one with the gen 2's (he is known here as Vassilis Tsafatinos). He tests cheap swords by bashing them into a tire pell thousands of times.

Well, the funny thing is that both(one for sure, probably the other too) of these gen 2s survived 2000 + strikes on the pell (and he hits hard). Both were straight as an arrow. A few cuts on tatami, and both are S shaped.

Just goes to show you....swords are designed to survive specific things unharmed. These are not always the things that we would like.

New York Historical Fencing Association
www.newyorklongsword.com

Byakkokan Dojo
http://newyorkbattodo.com/
View user's profile Send private message Visit poster's website
Mike West




Location: North Carolina
Joined: 06 Dec 2003
Likes: 4 pages

Posts: 84

PostPosted: Fri 19 Sep, 2008 8:29 pm    Post subject: update         Reply with quote

I've contacted an SCA armourer and, a sword cutler, but haven't received any reply. Since the sword had insurance, I contacted the seller and, UPS will pick up the package to inspect. I plan on highlighting the taped over cut and, deep fold on the box with an explanation to check the sword blade and, note that the bend in the blade corresponds with the box damage almost exactly.

Hopefully I can get my money back. Otherwise, I'll be looking for an armourer for help.

I did try to bend the blade back into shape with quick, powerful pulls, but no luck. Too bad, as the sword felt very alive when I handled it. Quick and, very maneuverable.
View user's profile Send private message
Luka Borscak




Location: Croatia
Joined: 11 Jun 2007
Likes: 7 pages

Posts: 2,229

PostPosted: Sat 20 Sep, 2008 6:59 am    Post subject:         Reply with quote

Michael Edelson wrote:
Luka Borscak wrote:
Ah, if I knew that before I returned my bent Gen2 12th century sword... I loved that sword for some reason and I was very dissapointed when it bent. I couldn't straighten it's probably because I didn't know how...


Wanna hear something funny?

Do you know Bill Tsafa, the tire pell guy? We he was the one with the gen 2's (he is known here as Vassilis Tsafatinos). He tests cheap swords by bashing them into a tire pell thousands of times.

Well, the funny thing is that both(one for sure, probably the other too) of these gen 2s survived 2000 + strikes on the pell (and he hits hard). Both were straight as an arrow. A few cuts on tatami, and both are S shaped.

Just goes to show you....swords are designed to survive specific things unharmed. These are not always the things that we would like.


And if the bending on the mats happened first all would probably say it's the Gen2's bad heat treatment. Wink
View user's profile Send private message
Mike West




Location: North Carolina
Joined: 06 Dec 2003
Likes: 4 pages

Posts: 84

PostPosted: Thu 26 Nov, 2009 7:46 pm    Post subject: I was able to bend the blade back!         Reply with quote

The bend is back to almost straight! I had sent the blade back to the seller in 2008 in hopes of collecting on the insurance from UPS. Several false hope periods, including a call from UPS all came to naught. I guess UPS is a big and, bloated bureaucracy and, getting an insurance payment is next to difficult.

A few months ago, I had the seller send the sword back to me as I had an idea on how to bend it back using a wood worker's vice and, three blocks of wood.

Today, I was able to bend the sword back the opposite way with those materials and, the blade was bent back to nearly 100% straight. There is still a slight bend to one side, which is somewhat noticible when handling, although I'll try to bend it more tomorrow morning.
But, the vice was able to provide the constant pressure needed to bend the blade.
View user's profile Send private message


Display posts from previous:   
Forum Index > Off-topic Talk > bent blade, can it be made straight?
Page 1 of 1 Reply to topic
All times are GMT - 8 Hours

View previous topic :: View next topic
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum






All contents © Copyright 2003-2018 myArmoury.com — All rights reserved
Discussion forums powered by phpBB © The phpBB Group
Switch to the Basic Low-bandwidth Version of the forum