1. Get the right mold material: The first thing you need to have for creating a plastic part is a mold. The mold is a female replica of your original part. You need to create your mold with a material called RTV (Room Temperature Vulcanizing) slicone rubber. The best part of RTV is it comes in the form of liquid until you add the required catalyst.
2. Make the mold: You need to have one master part for making the mold. The master part should be similar to the actual part. Place the master part glued inside a cardboard box (this will be the mold box). Suppose, you want to make a door knob in your home. You will need to fix the master door knob by using glue in the cardboard box. Mix the "tin" catalyst with the RTV liquid and pour the mixture into the mold box you created. RTV takes 20-24 hours for setting up. After that you can remove the master part to get the mold cavity.
3. Get the casting resins: The just-prepared mold cavity is to be poured with casting resins to get the actual plastic parts. Casting resins are available in two-part liquids.
4. Pour the cavity: The two parts of the casting resins need to be mixed thoroughly and to be poured immediately into the mold cavity. It will not take more than 10-15 minutes for the casting resins to set in the mold cavity.
5. Remove the part: Finally, after setting the casting resins to the mold cavity, release the plastic part from the mold.