Mujitsu and Tairaku's Shakuhachi BBQ

Hi Matt. Welcome to the forum.

(Parts of the following are from a post of mine in another forum. These are thoughts concerning my experiences making long, wide bore shakuhachi of about 5 to 6cm width)

In a design sense, one way to think of shakuhachi is that it has a window of bore/length possibilities. (some refer to this as aspect ratio) A thinner bore to length ratio usually results in a focused, cleaner tone. A wider bore to length ratio usually results in a breathier tone. Going too far in either direction results in poor tuning and tone. A bore/length ratio somewhere in the middle results in better odds for good octave tuning without extensive bore work.

Some like the tone quality of wide bore to length ratio shakuhachi. I've found that pushing this ratio to the extreme results in a very nice tone. The trade off  with these flutes is that the upper registers are often initially out of tune or weak. This can be improved and corrected but it requires attentive bore adjustment.

Concerning tone with wide bore shakuahchi, there seems to be a point where the tone suddenly improves dramatically into a glowing, vibrating foghorn like sound. This is achieved by the right combination of adjustments of nodes, choke point, blowing end and rootend diameter as well as hole size and undercutting.

Concerning the blowing end logistics, Tom Deaver mentions, "On some shakuhachi, and even hochiku, a thin ring of bamboo is inserted into the utaguchi end to replace part of the removed membrane and is then filed out in the area where the breath is blown over the edge, leaving a sort of crescent shaped partial ring of different color and texture. Sometimes material other than bamboo is used to reduce the size of the opening at the utaguchi, car body putty, resin, whatever."

With a wide bore to length ratio, the holes will need to be moved a little north.

I hope this helps. Good luck!

Ken

"I’d like to stay with the organic flavor of the bamboo if at all possible."

Leave more of the node when you're making it...

matthew wrote:

Anyone have thoughts on pliable materials other than the automotive putty approach?  I’d like to stay with the organic flavor of the bamboo if at all possible.

Hi Matthew.  Building up an inner circumference or crescent with bamboo saw dust and very thin super glue (cyanoacrylate) works well.  You end up with a color-matched (or at least color-complementary) material that's permanent, waterproof, easy to file and sand, and can be polished for a smooth surface on the lips/chin.  I have narrowed and shaped the blowing end of several flutes this way.  You can easily close up and shape the inner diameter at the blowing end by 5 - 10 mm.

If you don't have a thin node top surface to build this material up onto, you'll have to hold the flute sideways and apply thin layers of dust, apply glue, wait a minute, rotate, and repeat. You can file the resulting inner ring to a perfectly smooth circle or ellipse.  (Always place the dust first, pack it and shape it, then add a drop or two of glue. Test/practice this on a scrap ring of bamboo -- it's very easy.)  Search for "cyanoacrylate" or "Hot Stuff" on the forums here for more talk.

That said, I think inserting a bamboo ring as Ken suggests is the most beautiful and organic solution.

-Darren.

Thanks everyone,
I have used hot stuff type glue mixed with powdered artist's pigment in the past working in a violin shop doing repair and restoration.  I found you could make a paste of any color and then set it instantly with an activator.  Worked well for ebony repairs.  I wonder if something like that might not work here. 

This time around I used a two part epoxy putty and fit a crecent shape into the opening.  After it was formed and cured I removed it and then super glued it in place.  It worked out really well, but I would like to try the bamboo ring next time.  I'm going to have to stock pile different size pieces bamboo to pull that off.

Matt