How To Make a Breakaway Glass Bottle Prop

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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”. Advantages; 1) castings are easier to make vs. hand rotational casting and 2) cured SMASH! castings have a uniform wall thickness. Disadvantage; finished castings lack a bottom, but this is rarely noticeable on 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.

1 - The original model is a glass beer bottle with the label removed. To contain the mold rubber, a cut line is marked 1'' over the top of the beer bottle on a cardboard mailing tube.	2 - A utility knife is used to carefully cut along the cut line.	3 - The tube is cut lengthwise to allow access to the interior.
4 - The glass beer bottle is hot-glued to the melamine baseboard.	5 - The bottle is held in place until the glue cools.	6 - Superseal is dispensed into a plastic cup.
7 - The Superseal is applied to the interior of the cardboard tube.	8 - We will use a small amount of a non-sulfur based clay for the next step.	9 - The clay is applied over the pour spout of the bottle, to create a seal.
10 - Important - Silicone rubber can bond to glass. A thorough coating of Ease Release 200 is applied as a separator.	11 - The tube is placed over the bottle.	12 - Care is taken to center the tube around the bottle.
13 - The tube is hot-glued to the melamine base board.	14 - The lengthwise cut in the tube is sealed with hot glue.	15 - The B component of a trial kit of Mold Max 30 silicone is pre-mixed and combined with part A.
16 - The A and B components are thoroughly mixed.	17 - The mixed material is poured into a clean bucket for a double mix and pour.	18 - This material is mixed using a new, clean mixing stick.
19 - The material is poured in a thin stream over the bottle, to a level of 1/2'' over the bottle's top.	20 - The Mold Max 30 silicone is allowed to cure overnight.	21 - After the silicone cures, the hot glue is removed from the cardboard tube.
22 - The cardboard tube is flexed to reveal the silicone mold.	23 - Using a razor knife, the silicone mold is carefully cut open 3/4 of the way down to a point where the rubber can be separated and the casting removed.	24 - The bottle is removed from the cut Mold Max 30 silicone mold.
25 - A registration notch is cut into the top mold.	26 - This notch will act as a registration point for the silicone core.	27 - The cardboard tube is replaced around the silicone mold.
28 - Rubber bands are used to hold the mold together tightly.	29 - Wax is melted in a 'hot pot' until it is liquid.	30 - The hot wax is carefully poured into the silicone mold and allowed to cool slightly.
31 - After approximately 1 hour, the excess wax is poured out, leaving a hollow wax coating or 'skin' casting on the inside mold cavity.	32 - After 1 hour, the wax has completely cooled and the cardboard support is removed from around the rubber mold.	33 - The wax skin casting of the bottle is carefully removed from the mold.
34 - Residual wax flashing is removed with a razor knife.	35 - The bottom of the wax is heated using a propane torch.	36 - This results in a smooth bottom on the hollow wax casting.
37 - The interior of the mold is sprayed with Ease Release 200.	38 - The wax casting is replaced in the mold.	39 - The cardboard tube is replaced.
40 - Rubber bands are again applied to hold the mold together tightly.	41 - The silicone surfaces are sprayed with Ease Release 200.	42 - Hot melt glue is applied to the top of the cardboard support to seal the cut and prevent liquid rubber from escaping.
43 - Mold Max 20 silicone is measured out.	44 - The mix ratio of Mold Max 10 is 100A:10B.	45 - The Mold Max 10 is mixed thoroughly.
46 - the mixed silicone is poured into a new, clean bucket.	47 - The material is mixed again, using a clean, new mixing stick.	48 - The Mold Max 10 is then poured into the hollow wax casting.
49 - The material is poured to the top of the tube, over the previous silicone.	50 - The rubber is allowed to cure overnight. Next day, the rubber bands are removed from the cardboard tube.	51 - The cardboard tube is removed.
52 - The Mold Max 10 core is carefully separated from the Mold Max 30 outer mold.	53 - Some Mold Max 10 may leak into the Mold Max 30 mold.	54 - The excess Mold Max 10 flashing is easily removed with a razor knife.
55 - The Mold Max 10 rubber core is separated from the hollow wax skin.	56 - A 1'' (2.5 cm) pour hole is cut at the top of the mold in the center.	57 - The hole gives access to the mold cavity for pouring the liquid SMASH! plastic.
58 - Prior to casting SMASH! Plastic into the mold structure, Universal Mold Release is applied to the rubber core. This release agent will give the finished SMASH! Plastic a gloss finish.	59 - The inside of the Mold Max 30 mold is also sprayed with Universal Mold Release.	60 - The outer Mold Max 30 mold is placed around the Mold Max 10 core.
61 - Rubber bands are used to hold the mold together.	62 - The SMASH! plastic is measured 1A:1B by volume.	63 - So-Strong brown pigment is added to the part B of the SMASH! plastic.
64 - The SMASH! parts A and B are combined.	65 - The material is thoroughly mixed.	66 - SMASH! plastic is poured into the mold in a thin stream, to reduce air bubbles.
67 - After curing for 90 minutes at room temperature, the SMASH! bottle is demolded.	68 - The Mold Max 10 core is carefully removed from the fragile SMASH! casting.	69 - The bottom of the SMASH! bottle is carefully sanded flat.
70 - The breakaway bottle is left to harden overnight to become fully brittle.	71 - Labels are adhered to the breakaway bottles. It is difficult to tell they are not the real thing!	72 - The bottle is ready to be smashed on stage or on screen.