robotronski

BTW, we typically call the original you make the mold from a "PLUG".

For example, a boat builder would spend a year making an original wooden boat mock-up of the hull shape. This mock-up is absolutely perfect. It has to be or any flaws will be replicated many times.

Then they glass it and sand it smooth. Now they call it a plug.

Wax the plug, cover it with many layers of fiber glass, and before removing the glass shell from the plug, they attach an external skeleton to it to give the mold additional strength.

Then a crew drives soft plastic wedges to separate the mold from the plug and now there is a an exact copy of the exterior lines of the hull.

Next time you go out on a boat, look at all the unique molds it takes just to make the deck and dashbaord area nice. Its a ton of prep work.