yari shaft construction

[Marius]

I have always wondered how the shaft of a yari is made. I think it should be made from one piece of wood (ash?). Then again, how did they make the hole for the square nakago in the shaft? I have found no reference on this. Any ideas? A friend of mine supposes the yari shaft is consists of two pieces, just like the tsuka of a sword.

 

What are the facts?

[IanB]

Mariusz, Almost all staff weapon shafts in Japan are of red oak, kashi. I did once have a yari in which the shaft was made from triangular sections lengths of bamboo, glued up like a fishing rod and then rounded and lacquered but that was unusual. For most shafts, the top section is then split down the centre for the length of the tang of the spear or naginata blade. After hollowing out for the tang it is glued back and then bound with thread before lacquering. The various rings and mounts are to stop this detached piece from coming loose again.

Ian Bottomley

[machinist]

I used to have jumonji-yari many years ago with a short stub of the original shaft that was made of laminated bamboo as Ian described.

I imagine it was a very light and strong spear shaft.

[estcrh]

Mariusz, Almost all staff weapon shafts in Japan are of red oak, kashi. I did once have a yari in which the shaft was made from triangular sections lengths of bamboo, glued up like a fishing rod and then rounded and lacquered but that was unusual. For most shafts, the top section is then split down the centre for the length of the tang of the spear or naginata blade. After hollowing out for the tang it is glued back and then bound with thread before lacquering. The various rings and mounts are to stop this detached piece from coming loose again.

Ian Bottomley

Good information! I always like those..how did they do that?... questions and answers

[loui]

I have had several that are split like Ian says, hollowed out but there is a small wedge cut the length of the nakago - then glued in place and wrapped/banded.

 

Louis

[Jean]

You shall have to translate it, it is the way the split banboo fishing rods are made.

 

Same principle :

 

http://www.canne-refendu.com/index.php

[Klop]

Hi Mariusz,

 

I have seen 2 poles "naked" and both were of the U-shaped type where as much of the original wood as possible is left intact. This produces 3/4 of ongoing fibres instead of 1/2 when the topsection is split in half like a sword tuska.

A tapering tunnel is chiseled out for the nakago and then a new wedge of wood closes the gap. The inserted wood was not oak but a lighter wood. After closing the gap reinforcement like strings, laquer, same and metal rings can be used.

 

I noticed that on the ribbed pole it were all individual strings. Of course a spiral of one piece would be easier to make but if cut the whole thing could come off. With individual strings if a few are cut the rest will remain intact. As I understand it the long nakago is also an internal protection against the pole being cut through. In the west long strips were used on the outside of the pole for the same purpose (and have a look at sodegarami, in this case spiked strips prevent grabbing the pole).

 

Here are some pics, one of an original pole and a few of a pole I made from oak following the same method (shimosaka yari, head 30 cm, tang 30 cm). Working the pole is easier when it isn't round yet, when the lid is glued in place just remove what's not needed anymore.

 

Kind regards,

Eric.

[watsonmil]

Hello Eric,

I just finished making a Yari Pole, .... I wish you had posted this information a couple of weeks ago. It would have made my task much easier. It only goes to show, ... there is always something new and interesting to learn. A great piece of shared knowledge. Thank you for posting. ......... Ron Watson

[Marius]

 

Here are some pics, one of an original pole and a few of a pole I made from oak following the same method (shimosaka yari, head 30 cm, tang 30 cm). Working the pole is easier when it isn't round yet, when the lid is glued in place just remove what's not needed anymore.

 

Hi Eric,

 

fantastic pics, very valuable information, thank you :-) I think I know right now how to proceed with my yari.

[estcrh]

In the same vein, here is a picture of a naginata saya showing the 2 halves.

[loui]

Hi Mariusz,

 

I have seen 2 poles "naked" and both were of the U-shaped type where as much of the original wood as possible is left intact. This produces 3/4 of ongoing fibres instead of 1/2 when the topsection is split in half like a sword tuska.

A tapering tunnel is chiseled out for the nakago and then a new wedge of wood closes the gap. The inserted wood was not oak but a lighter wood. After closing the gap reinforcement like strings, laquer, same and metal rings can be used.

 

I noticed that on the ribbed pole it were all individual strings. Of course a spiral of one piece would be easier to make but if cut the whole thing could come off. With individual strings if a few are cut the rest will remain intact. As I understand it the long nakago is also an internal protection against the pole being cut through. In the west long strips were used on the outside of the pole for the same purpose (and have a look at sodegarami, in this case spiked strips prevent grabbing the pole).

 

Here are some pics, one of an original pole and a few of a pole I made from oak following the same method (shimosaka yari, head 30 cm, tang 30 cm). Working the pole is easier when it isn't round yet, when the lid is glued in place just remove what's not needed anymore.

 

Kind regards,

Eric.

 

Excellent example, that is exactly how my 26 inch Kanabo Masatsugu was mounted. Well done.

 

Louis

[Carlo Giuseppe Tacchini]

A tapering tunnel is chiseled out for the nakago and then a new wedge of wood closes the gap. The inserted wood was not oak but a lighter wood. After closing the gap reinforcement like strings, laquer, same and metal rings can be used.

 

 

Eric, good job.

 

Guess you're the right person to post also the way Naginata Nakago were inserted in an oval staff, maybe with pictures.

[Henry Stewart]

Hi Mariusz

 

I have just had a carpenter friend make me a shaft for a 2ft long yari with a long Nakago. I wish now I'd seen some of the foregoing explanations first now.

What he did was obtain an inch and a quarter pole of ash wood already preformed. Place it in a lathe and drill down the centre the length of the nakago with a pilot drill (extra long). He then got a piece of 3/16th wrought iron square form bar and heating it several times actualy burnt out the excess wood. The yari fit very well,the worst job was locating the hole. This avoided splitting the wood and therefore kept its total integrity.

 

Henry

[Klop]

Gents,

 

thank you for the "thumbs up" I would love to see those huges blades of yours!

 

I'm sorry I didn't share sooner.... It turns out there are several ways to achieve the same result.

The easiest; get a fukuro yari! But somehow the Japanese themselves favour the nakago type considering the production rates.

 

The burning with hot bar poses another issue to be dealt with; the nakago tapers so when getting deeper the hot bar must become thinner? Or just burn a equally sized hole over the entire length and prevent rattling by inserting a loose wedge?

Henry, can you tell us how your friend solved this?

 

Carlo, Unfortunately I haven't got a naginata nor have I seen the pole concept on these. Difficult choice; splitting like a sword tsuka or the tunnel idea again. When tunneling I would pick the flat side of the pole so the back and belly wood stays intact. Second argument is that because of the shape of naginata nakago this approach is easier to achieve a good fit.

 

Mariusz, I didn't mention earlier; Before chiselling the tunnel you could make two lenghtwise cuts with a saw to create the walls of the tunnel. What's between these two cuts can be removed more easily. I feel a Japanese type saw with action on the pulling stroke works better than a western push action. Will you show us your results?

 

 

Kind regards,

Eric K.

[Henry Stewart]

Eric K;

 

As far as I can guess the pilot drill had a slightly larger diameter than the first say two thirds of the nakago the shape of which was more or less rectangular. The top half he tapered with a small width long modellers chisel to more precise fitting,after burning out the square shape which was too small until chiselled. When inserted there appeared a very slight sideways movement which was taken up entirely by inserting the bamboo pin which seemed to lock it in place.

He was reasoning this was one way it could have been done originally The thin end of the nakago now sitting neat on the bottom of the hole being supported.

 

Henry