How did the japanese do it ??

[artcreek]

I have been a knifemaker for a few years, and I specialize in japanese blades. In all these years of making knives I have put a few bo-hi or fuller groove in quite a few pieces . today It is easily done with modern machinery (milling machine) Does anyone know how the japanese did it by hand ????? was it done with files or what seems it would be extremely labor intensive ?? JIM

 

[indian george]

Checkout Don Fogg's site, I believe he has a tutorial on it.

 

[Dave Bowen]

There is a tool called a fuller tool. It's a pulling tool with a hardened metel insert. You pull it along the blade much like a draw file, and eventually, you cut the fuller into the blade.

As IG said, there is a section on Don Fogg's website about the technique.

 

[tonyccw]

I believe it was done with chisels and scrapers.

 

[bryce]

Some people can forge it in as well, although i imagine it aint easy

 

[Stacy E. Apelt - Bladesmith]

You use a fuller scraper. See Don Fogg's site. It is surprisingly fast to draw one (the motion is a draw, or pull). Forging one in requires allowing for the spread of the steel and can really mess things up if not done right.
Stacy

 

[Keith_H]

off topic, what flux did the feudal Japanese use to weld the steel together?

 

[Original]

I know that the fullers on the Himilayan Imports Khukuri's are hand forged in, I had always assumed that the Katana's were too.

 

[A C Richards]

Flux they used was a clay slurry with rice straw ash mixed in. if you are looking for a good general book get "The Craft of the Japanese Sword" with Yoshindo Yoshihara and others. Explains much of the process but does leave out some details.

Chuck

 

[burke531]

The smiths and photos that I saw while in japan were actually using a tool that was shaped like the groove on cross section and a push cut was used. thety also used their sens with a push cut insted of a pull cut.

 

[bobby.t]

^ That's odd, since pretty much any American tool that involves a push is done with a pull in its Japanese form (saws, planes, etc).

 

[L.K.Smithy]

i agree, thats odd. and i find push cuts awkward for most things also. i have made many of my tools so they can be used for a pull. iv been planning on making a sen and fuller scraper for a while. oh where does the time go...
-Lou

 

[Karl B. Andersen]

Know what that groove is for?
Think of this, back in the "day", the people creating things out of steel with the forging method, or any method for that matter, didn't have Admiral Steel, or Fastenal, or Crucible, etc. just down the road or a day away with UPS! All they had, was what they had.
Steel was VALUABLE!!
Imagine what it took to build a furnace and make your own wootz.
Anyway, you have this piece of steel and you're forging along and realize you either want it a little longer or a little wider! You don't grab another piece of flat bar stock out of the corner - you only have what you have.
So you can push that edge down, but you need to get the steel FROM somewhere.
You smoosh down that groove up by the spine, and it moves your edge down. What was "in" that groove is now usable steel somewhere else.
It was just a matter of availability and stock resources.

 

[David Wesner]

Here's a link to a thread that shows an excellent version of a fullering tool.
It was made by one of our very own ShopTalk phenoms, B Finnigan :thumbup:http://www.bladeforums.com/forums/showthread.php?t=522813
Not only a pic of the tool but a video showing it in use too. Excellent tool finny

 

[artcreek]

Thanks for the info everyone, I appreciate it thanks you know you do some things and you take them for granted . Thank god for the milling machine.......JIM

 

[David Wesner]

I hear ya brother :thumbup:

 

[Raymond Richard]

Now to get back to your question: How did the japanese do it ?? Sameway as us.

Karl, I just bowered the book that Woodchuck mentioned. Don't recall seeing the groove being fullered but then I may have missed it. What you said sure makes sense to me.

 

[A C Richards]

Yoshindo shows the cutting/fullering tool he uses. He does not forge it in but cuts it in. He has a handle he puts various chisels or gouges in to cut the groove desired. Page 96..

Chuck

 

[burke531]

bobby.t
^ That's odd, since pretty much any American tool that involves a push is done with a pull in its Japanese form (saws, planes, etc).

If you look on page 84 in the craft of the japanese sword you will see two pictures of Yoshihara San pushing his sen away from himself while cutting. Additionally on page 97 you can see him cutting the groove in a sword with a push cut.

 

[A C Richards]

I use a sen in both directions. Works great for removing a lot of steel. I do not feel it is at all dangerous in the draw method. However pulling one of those chisels or gouges toward your body would be an accident waiting to happen. Fullering or forging the groove was done for the reasons mentioned above and also to lighten and strengthen the blade. At least this is what some who have much more insight than I have indicated.

Chuck