Lining up the Nakago(tang) and Sao(neck) for glueing

Building/Repair
#1

Hey team,

I'm a first time Shamisen builder and I'm at the point where I have cut the

joints, and am ready to glue the Nakago (tang) and the Sao (neck) together. My
worry is getting the resulting piece to fit together into one straight piece. In
order to be a functional instrument where the strings run the length of the
neck at a consistent relationship to the neck, they need to be straight (please
correct me if I’m wrong here). After an initial trial, mine were clearly not fitting
together smoothly, so I added a shim and glued them together without any
tools just to see how it would go. . . As you can see from the linked pictures
on my blog, the results were less than adequate.

http://make-a-shamisen-with-jrm.tumblr.com/

 My question is this.  What means does one use to cut/file/shave down the

joints so they fit tightly/seamlessly, and what means (a jig, home-made vice,
etc.) can you use to measure the straightness and ensure that they stay
straight as you begin to glue them together?

 Can anyone out there in Bachido land who has some experience in this area

offer any insight to help me? Thank you in advance for any help or guidance
you might be able to give me.

Warm fuzzies,
Joel Mankey

#2

Hi Joel,

For your first shamisen, it’s pretty darn snazzy. :slight_smile: (Sure looks a lot better than my first shamisen, let me tell you)

My question is this. What means does one use to cut/file/shave down the
joints so they fit tightly/seamlessly

Do you mean in order to get the base of the sao and the base of the nakago to fit flush together? I first use a file to get the surfaces smooth (as it may be rough after using the saw). Then I use a chisel as a scraper, to lightly shave away wood until it’s perfectly flat (which you judge by placing a straightedge on the surface). Obviously, that blunts the chisel, so I use my “beater” chisel (which I sharpen with a bench grinder, not with stones).

can you use to measure the straightness and ensure that they stay
straight as you begin to glue them together?

To judge the left-right straightness: I basically hold the sao up to my eye, as if I was looking down a rifle. Then tilt the sao up until you see the tip of the nakagosaki. if it’s straight, it should line up in the middle of the sao (make a mark on the middle of the sao’s topside so you can line it up). If it’s slightly to the left or right, you need to make a slight change (only shave away a little wood and check again).

The up-down straightness is less important. Clamp the two pieces together and put a straightedge on top. Then just use your eye or a ruler to see how straight it is.

Hope that helps! :slight_smile:

Kyle

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