best edge angle for sharpening a katana at ?

[eros69]

Hi there. Have been asked to put an edge back on a blunt katana for a friend of mine.It's not an old one so it wont be devalued by the process, unless I mess it up of course. Can any one tell me if swords edge angles are similiar to knives or do you have to sharpen em differently. Have never sharpened a sword before and it's not mine so I want to make sure I get it right for him.Any help and advice would be gratefully recieved.(The sword is a mark 1 last legend katana. Dont know if this info helps)

[Edd-UK]

have you tried 'sword forum'??

im not a member so i dont know what info they would have but sounds like a good place to start :)

[eros69]

Thanks Edd. Never thought of that. Will give it a go. Cheers mate. :)

[ggfh666]

They are all flat ground. Starting from the ridge keep things flat.
How blunt is blunt?

Last Legend's Ultra-fine alumina ceramic rod is not to sharpen a blunt but to make it as sharp as it was before cutting.

And Swordforum certainly has some knowledgeable people around. Just don't say it is an LL or they start a war again;)

[praktis]

they sure do have something against LL don´t know why.
they are a bit different than a traditional katana, but then again they never say that they are making a traditional katana.
the MK IV bear katana i had was great to cut with.

/Roger

[ggfh666]

they sure do have something against LL don´t know why.

/Roger


Because they don't have one?
Things are chan ging a bit now, more balanced.
Most were very Bugei/Paul Chen oriented. There a number of new players on the market offering cheap cutters. It all depends on what you need, expect.

[8thsinner]

You would be lucky to find more than a few percent of the traditional shinken with a flat ground blade.
They are designed extremely close to it at times but they are almost always convex.
The amount of convex is described as niku, either little or a lot.
More beefy niku is used for harder targets, where as little niku is for soft targets.

eg bamboo and rolled mats.
There is a reason the standard apprentice ship of a polisher was ten years...Try convexing with straight stones it's not easy.

Some modern blades are coming out in and can cut with flat edges, but the shock transfer would make them dangerous unless well tempered.

[Mike Blue]

The amount of convex is described as niku, either little or a lot. More beefy niku is used for harder targets, where as little niku is for soft targets.
There is a reason the standard apprentice ship of a polisher was ten years...Try convexing with straight stones it's not easy.
Some modern blades are coming out in and can cut with flat edges, but the shock transfer would make them dangerous unless well tempered.

Niku is probably a better assessment of how many times or how badly the blade has been polished in its lifetime. A new sword will have more niku. An old sword or inattentively polished one will have less.

Cutting technique is far more important than the edge, the niku or the character of the target. Some good swordspersons can cut with flat edges or unsharpened blades. Shock transfer is irrelevant with correct technique.


Eros: you should attempt to figure out the angle at the edge. Let me cite a living reference who plays on this list, who had a very knowledgeable and talented polisher write this chapter. http://us.geocities.com/alchemyst/niku.htm

Then have your sharpener attempt to match that angle. Do not put a secondary bevel on the sword, please, even if it is a throwaway piece of junk.

[eros69]

Thanks for the advice all. That link was most informative Mike cheers.:)