Mujitsu and Tairaku's Shakuhachi BBQ

Windom wrote:

Is there anything I could do to try to make sure that at least some of the bamboo doesn't fall apart on me?

I find it's safer to enlarge holes with a dremel sanding disc. You can also wrap coarse sandpaper around a drill bit. As you found out, a drill bit used alone to enlarge holes can grab and split the bamboo easily.

Windom wrote:

This left me wondering what's the proper way of positioning the utaguchi in relation to the node.

Some older jinashi shakuhachi include the ridge behind the utaguchi. I prefer to grind it smooth and flare it open slightly. Sometimes it feels better to include the ridge. If you include the ridge, I think the key is to make sure that it is deeper than the one or two mm. it looks like in your drawing. That way it won't crumble an ruin the edge.

Let me know if this makes sense. Here's a drawing: It's exaggerated but you get the idea.

Ken

Thanks for the comments! I get what you mean. The ridge is indeed slightly longer - my pic wasn't to scale.

I have been using 60 grit around drill bits to bring holes into rough tune but for bamboo it seems I need to change my evil ways and start from a smaller hole.

No charcoal baking applied, unless someone in the supply chain did it. I don't suppose an electrical stove is any good?

The bamboo isn't green. It looks old and dried, a sort of yellowish light brown.

That bang that just drove your ears 6 shaku into your skull was a 4-node low E flute splitting after my drill snagged midway through the first hole. This is like trying to defuse a bomb!

How are holes made by burning in a controlled fashion? What sort of a tool does it take?

Mujitsu wrote:

A forstner bit will drill a clean hole in bamboo without splitting. 3/8" is a good size to start with. They are available at most hardware stores. Bits from Mejiro are even better!

Forstner bits are awesome.  So are lip-and-spur bits -- that's what I've used with success.

Advice...  Secure your bamboo on a drill press & table to avoid tearing bamboo skin around the hole edges as you drill and especially as you pull the bit out if it has cutting lips around the circumference.  Don't ask me how I know. 

-Darren.

Windom wrote:

How are holes made by burning in a controlled fashion? What sort of a tool does it take?

If you are in an EXTREMELY well ventilated room or are outside, I suggest trying a small grinding stone bit on a dremel (or any other of the high speed rotary tools out there).

the grinding stones can be found in widths of about 4 mm and up. 

One must be careful to not let the grinding stone bit "skip" across the surface of the bamboo but that's about it.  The "skipping" has happened to me only once or twice and was really a result of me just not paying enough attention at the moment.

The grinding stone literally burns through the bamboo (completely through) and can be used as a sanding tool as well. 

I think the biggest benefit is that the burning process doesn't provide an opportunity to "catch" on the bamboo.  Also, I believe that the burning seals the holes quite nicely.

The biggest drawback is the large amount of smoke produced.