---
title: Inject (using the extruder)
slug: inject-using-the-extruder
step: 8
howto: make-plaster-moulds-for-large-products
tags: ["product","injection","extrusion","mould"]
category: Moulds
difficulty: Medium
time: < 1 week
location: 
---
# Step 8: Inject (using the extruder)
Begin by heating your plaster mold. As it heats, activate your extruder and prepare the plastic. Once the mold is sufficiently heated, commence the injection process. The duration may vary, from several minutes to several hours, depending on the product's size. In this instance, it took approximately 2.5 hours to fill the mold.

When the plastic reaches all reference points you've drilled, the product is fully injected. At this juncture, deactivate your heat guns and extruder. Ensure all holes are plugged to maintain pressure within the mold.
![IMG_3668 copy.jpg](/resources/howtos/make-plaster-moulds-for-large-products/img_3668_copy.jpg)