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tools: calipers

updated fri 27 jul 01


Michael Sowers on thu 26 jul 01

I would like some information on the Japanese method of measuring pots for
depth and width while throwing off the hump. I have seen them (the tools)
but do not know what they are called or how you use them. From my not so hot
memory, they looked like two crossed sticks. I am sure there are some people
on the list that are knowledgeable in this area and any information is
greatly appreciated.

Classic Lines Pottery
Michael Sowers
Tel: 208-331-0803
Fax: 208-331-0487

Brenda Z on thu 26 jul 01


I have never used these tools, but there is a short description of them in the book Inside Japanese Ceramics by Richard L. Wilson.
The tool is called a dragonfly measuring gauge or tombo. One is usually made for each model in the production line (it doesn't
appear to be adjustable). The tool consists of three sticks. There is a vertical stick that is equal in length to the pot depth.
There is a horizontal stick that is centered through the middle of the vertical stick, and it is equal in length to the width of the
pot. There is a second horizontal stick attached to the top of the vertical stick, for holding the tool while it is lowered into
the pot.

Brenda Z.

Snail Scott on thu 26 jul 01

At 11:07 AM 7/26/01 -0600, you wrote:
>I would like some information on the Japanese method of measuring pots for
>depth and width while throwing off the hump.

They're pretty simple, and you can make them from
just about anything - twigs, straws, bits of wire.

You have a different tombo for each size pot.
The vertical is tied exactly in the center of the
horizontal arm. The horizontal arm measures the
diameter. The lower portion of the vertical measures
the depth from the rim to the center of the bottom
(while the horizontal is just level with the rim).
The upper portion of the vertical is what you hold.

It won't keep you from varying the curvature, but
the depth and width will be consistent. (Japanese
techniques often involve ribs (oji) which are made
for each pot's specific interior contour, so they
control the curvature that way.)