Modeling the Canal System: Test Un

TODAY, I made a test model of the canal system in 3D using clay and silicon. There are two parts to the model: a positive mold and a negative mold. I want to make a negative mold that can carry water (like the canal!): it should be elastic, somewhat clear, and able to withstand heat (steam?). The positive mold is made out of clay. I use clay because it enables me to cast a positive which is water soluble. This is necessary for removing the positive mold after the negative is cast all around it (like taking out a 'crunchy candy bar' from out of its delicious chocolate shell without damaging the shell, except at its ends). The negative mold is made from silicone. I am testing this to find out. Other materials I thought of using but nixed included balloon rubber, a latex material. It has greater elastic properties than silicon, which could prove advantageous. But it wears down very easily.







Top: Making the clay positive. A section from the 1:1000 scale drawing of the canal. Behind it stands one of the two jugs of silicon mixes; the two part mixture is easy to handle, and sets in about one half hour.

Middle: Covering the positive with the silicon. I use a spatula to spread the silicon over the clay. Several layers can be added through the curing process. I can even embed 'stuff' into the silicon, or draw on it too, with magic marker. I have spread the silicon in uneven layers, a way to test different thickness properties.

Bottom: The clay and the silicone have now been separated. Also, a photo of a spritzer, one of my favorite modeling tools.