How To Make a Breakaway Glass Bottle Prop


SMASH!® Plastic was developed for making breakaway glass bottles, windows, vases, jars, etc. It is easier to use and more consistent than other breakaway glass products making it the clear, economical choice. Used as directed, breakaway glass bottles made with SMASH!® Plastic look just like glass, break just like glass and sound just like breaking glass.

Making a breakaway glass bottle starts with making a silicone rubber mold of a real bottle. The rubber mold can then be used for casting SMASH!® Plastic to make the breakaway glass bottle.

Casting can be done two ways:

1. The liquid SMASH!® Plastic can be rotationally cast inside the rubber mold. As the liquid plastic builds layers and gradually cures against the mold walls, the plastic cures to a uniform thickness. The disadvantage of rotational casting is that it should be done using a rotational casting machine for best results and this equipment is expensive. Hand rotational casting involves a steady hand and a lot of trial and error resulting in inconsistent results and wasted material. 

2. The second involves using silicone rubber to make what is called a two-piece “cored mold”. There are two advantages to this method, first the castings are easier to make verus hand rotational casting. And second cured SMASH! castings have a uniform wall thickness. The disadvantage is that finished castings lack a bottom, but to is rarely noticeable on a stage or in a film. 

The following gallery takes you step by step through the process of making a two piece cored silicone rubber mold of a beer bottle and then using that mold to make a breakaway bottle using SMASH! Plastic. 

Note: Making a two-piece cored mold is an advanced mold making technique. Previous mold making experience is recommended before attempting.


Materials Used in this Tutorial

Step 1: Preparing Model