Rubber fishing lures are actually made of soft plastic. A thick milky white coloured liquid, Plastisol turns into a thick clear liquid when heated. When the heated Plastisol cools, it forms a durable non-toxic clear soft plastic. Before the Plastisol cools, you add colour and or glitter. To form the Plastisol into a soft plastic fishing lure, you pour the liquid material into moulds. The shape of the mould determines the shape of the soft plastic lure.
Coat the inside of both halves of a plastic mould with non-stick cooking spray.
Align the two mould halves. Slide one C-clip over each side of the aligned mould halves to keep them from coming apart.
Mix the Plastisol thoroughly with a wooden stir stick.
Heat the Plastisol. Pour the desired amount of Plastisol into a microwave safe measuring cup. Set the measuring cup in a microwave. Set the microwave to one minute, start the microwave and allow the Plastisol to heat. Stir the Plastisol and heat it for an additional 30 seconds. Insert the tip of a cooking thermometer into the Plastisol. If the temperature is below 163 degrees Celsius, continue to heat the material.
Add colouring and glitter (if desired) to the heated Plastisol.
Coat the O-ring and plunger of a mould injector with non-stick cooking spray.
Set the cylinder of a mould injector on a worktable with the open end of the cylinder facing up. Fill the cylinder 3/4 full with the heated Plastisol.
Slide the end of the injector plunger containing the O-ring into the top of the mould injector. Flip the mould injector over and push down on the cylinder until Plastisol comes out the tip of the mould injector.
Slide the fill opening of the plastic mould over the small filling orifice of the mould injector.
Push down on the plastic mould until Plastisol fills the reservoir on top of the mould.
Set the filled plastic mould aside to cool.
Remove the C-clips from the mould, separate the two halves of the mould, pull the cooled bait from the mould. Cut the excess plastic from the soft lure (sprue) with a razor knife.
Add salt to heated Plastisol to add scent to the finished soft plastic lure. Wear leather gloves when working with heated Plastisol to avoid potentially serious burns.