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Lil Dave
23rd July 2000, 01:44
I live in an area where I cannot attend a class on kenjutsu, nor view another's bokken. I would like to construct one out of some black walnut that I have. If anyone could direct me to a website where I could see many different bokken, I would much appreciate it. I would also like to understand a bit about the different styles and purposes of bokken. Thank you.

Dave Buck

Joseph Svinth
24th July 2000, 01:05
Try http://sdksupplies.netfirms.com/cat_bokuto.htm ; also follow the links you will find at http://www.uoguelph.ca/~kataylor/woodwork.htm .

Suggestions for constructing wooden weapons at home are provided at http://www.uoguelph.ca/~kataylor/bokuto.htm .



[Edited by Joseph Svinth on 07-23-2000 at 07:08 PM]

Gordon Smith
25th July 2000, 14:28
Myself, I start off with a rectangular blank a little larger than the cross section of the bokken I wish to build.

I've got a steam box and a jig for bending. The box is simply a plywood box, about 4"x8"x5', with removable caps on either end. I've got a series of dowels running horizontally to suppor pieces inside. I also drilled a few holes through the bottom for pressure relief. At on end of the box, I've got some plumbing fixtures that accept a hot water line that attaches to a common teakettle.

My jig is a precut curve of MDF, with a 1/8" steel strip attached to a variable width stop. An adjustable stop is on the other end of the strap

I cut my wood to length so that the straight piece just fits between the two stops on my strap. Then I adjust my steambox so that the steam inlet is lower than the other side. I turn my gas stove on high, and let the thing cook for a bit.

When I notice some steam coming out of the box, I take my straight piece of wood, and slip it into the box. Leave it in for at least a half hour, sometimes longer (I run ebony for about 45 minutes). When I think I'm ready, I pull the blank out of the steambox, slap it into the jig, and pulling on the free end of the strap, force it to the curve I want. I clamp the whole thing down, and wrap it up in a blanket to slow down the moisture loss. If I want a gentle curve, I let it out the next morning. If I want to conform tighter to the curve, I leave it in for a day or two more. Whenever you bend wood, there's some springback when you pull it out.

If you're a first timer, I'd try it out on a not-so-nice section of your walnut. These things can crack before you work out steaming times or assembly speed, and I'd hate to see it happen on your good piece.

Once I've got the curve I like, then I go the the shaping phase, which is a mix of power and hand tools.

-G-

Lil Dave
25th July 2000, 20:31
Does anyone have any thoughts on whether or not black walnut is strong enough for contact? Someone recently told that it wouldn't be, and I don't want to waste a perfectly good piece of wood.

I don't quite understand you jig, either. If you could try to explain it in more detail, that would be wonderful. Also, should the entire bokken curve the same, or should the handle (tsuki?) be straight, with the curve starting immediatley after?

Gracias por la help

Dave Buck

[Edited by Lil Dave on 07-25-2000 at 02:35 PM]

Tony Peters
26th July 2000, 06:15
Originally posted by Lil Dave
Does anyone have any thoughts on whether or not black walnut is strong enough for contact? Someone recently told that it wouldn't be, and I don't want to waste a perfectly good piece of wood.

I don't quite understand you jig, either. If you could try to explain it in more detail, that would be wonderful. Also, should the entire bokken curve the same, or should the handle (tsuki?) be straight, with the curve starting immediatley after?

Gracias por la help

Dave Buck

[Edited by Lil Dave on 07-25-2000 at 02:35 PM]

Black walnut is most certainly NOT a good wood for a contact weapon. It is quite strong enough if you are going to say, hit a tire (Tanren uchi) however it does not have a good crush resistance. I have a Subrito that I made from some Virginia Black Walnut (it has a pink cast under bright light) that I use for suburi's, kata's and tanren uchi but contact I'm afraid that would destroy it.
As for steaming your wood to curve it...I've neverdone this (which is not to say that it isn't a worthwhile thing to do) I am most certainly of the more artistic school of thought...I prefer to let the wood show me what it can bear. I just look at the wood I have and try to match the flow of the grain to the curve of a Boken. Which has dictated that each boken is of a diferant curve. . It takes longer but "I" am more pleased with the results and for me I've had better luck than when I've tried to force a shape into the wood. If you need a contact weapon get some Hickory or Pecan (more or less the same thing) it ain't pretty but it is strong, craft the Walnut for solowork. Just my thoughts on the matter.

Gordon Smith
27th July 2000, 15:22
Ok, let's see if I can do this without slides (if I confuse you too much I can add drawings, I guess :))

I've got a 1/2" thick piece of pressboard (y'know, sawdust glued together, claiming it's wood), cut to a rectangular size as a base.

Attached to the top with drywall screws, I have a second pressboard piece with a curved edge. The curve was drawn (and later redrawn) using a thin curved slat of wood as a guidline for my pencil. The curve starts out straight, for as long as I want the tsuka, and then I begin a curve that is sharper than what I want the final product to be.

This is the hit-and-miss portion of the program. It's better to be too shallow, because then you can re-cut your curve and re-bend your piece. I also had some problems because I was making sword that would fit into saya, and this meant that the curve had to be artistically pleasing, and more importantly consistent or else the darn thing won't go in the saya!

The curve was cut on the bandsaw, and then sanded smooth.

At the end of the flat portion of the curve, I mount a stopblock and my steel strip, leaving space between the strip and the curve form that my bending blank will just fit into.

On the other end of the strip is attached a wooden handle, at the same length as my bending blank.

In operation, I slip my hot steamy blank into the jig (pause here for all the nervous giggling to subside). Grab the wooden handle, and force the blank to the shape of the curve. I fix the handle to the curve using a clamp, then wrap the whole thing up in a large towel.

-G-

Lil Dave
27th July 2000, 20:35
thank you, I believe I understand now. I may try that (depends on whether my dad trusts me to fool around with a bunch of his tools).

Dave Buck

TimHillman
6th August 2000, 07:18
Gordon,
Do you think that a steamed formed bokken is stronger than a bokken cut to shape without being bent? What wood do you think really stands up to a beating?

Gordon Smith
8th August 2000, 17:07
Gaaaaaasssssspppp!

Ok, up for air after finally finishing my doctoral defense, and the weeklong hell of revisions afterward...

For bokken strength, I try to stay within the lines. The grain of wood indicates its strength. It is easier for me to break a long piece of wood that has the grain across the short edge. It is also much hard to break wood that has the grain running the long edge.

When you split wood, you are splitting the grain, tearing it along the directio of the grain.

That's why I prefer bending my wood. That way, I can pick a blank that has straight, tight grain, and bend it to the curve I want which will give me the strongest end result. If I cut a random blank, I can end up with a perfect curve, but with grain pointing the wrong direction, and this means it will be more likely to break on impact.

For beating purposes, I like hickory. Another good one would be Bodock (Osage Orange), but I'm not terribly fond of the finished look.

-G-

TimHillman
10th August 2000, 04:16
Thank-you,
I always thought that osage orange would be a good wood,
I always thought that it was a good looking would.