Alternative way to measure the interior of a mouthpiece

Measuring the interior of a mouthpiece is not easy and it is difficult to get a good impression of the internal shapes of it. But this week I got an idea to do it with modelling plastic. The trick that spies use to duplicate keys.

Modelling plastic is very nice to do this. It is available in pellets and you can knead it after heating it with boiling water.

To be sure that the plastic comes out again the interior of the mouthpieces has to be greased with some vegetable oil.

And the I just push a part of the plastic in the bore and another in the chamber and wait until it is strong enough to pull it out again. The result is two copies of the interior of the chamber and the bore that can be measured quite easily.