---
title: Consider pros and cons
slug: consider-pros-and-cons
step: 1
howto: make-plaster-moulds-for-large-products
tags: ["product","injection","extrusion","mould"]
category: Moulds
difficulty: Medium
time: < 1 week
location: 
---
# Step 1: Consider pros and cons
Before you begin, it is important to note that there are some drawbacks to using this method. Plaster molds are not durable, so this may not be suitable as a common method for processing plastic.

However, it is an excellent way to create large, solid products and can be used as a prototyping technique. For instance, if you want to test the shape of a mold before it is milled into a block of aluminum.

You will need:
- Extruder machine
- Shredded plastic
- Casting plaster
- Mold release
- A model or object to replicate
- Melamine or plywood
- Heat gun
- Paint, chopped fiberglass, shellac (optional)
![IMG_3710.jpg](/resources/howtos/make-plaster-moulds-for-large-products/img_3710.jpg)
![IMG_3598.jpg](/resources/howtos/make-plaster-moulds-for-large-products/img_3598.jpg)