Working with thick acrylic sheets is very different from handling standard panels. Once thickness goes beyond 50mm, the process becomes more technical and requires better control of heat, tools, and cutting strategy.

This guide explains how to cut acrylic sheet, perform CNC machining, and finish with proper acrylic polishing, based on real production experience.

What Is Considered a Thick Acrylic Sheet?

In most industrial applications, thick acrylic sheet refers to:

50mm acrylic sheet
80mm acrylic sheet
100mm+ acrylic blocks
up to 200mm–400mm cast acrylic

These thick plexiglass sheets are commonly used in architectural projects, aquariums, high-end displays, and custom fabrication.

Table of Contents

1. How to Cut Thick Acrylic Sheets

Panel Saw Cutting (Up to 80mm)

For straight cuts, a panel saw is commonly used for acrylic sheet cutting.

suitable for standard production
high efficiency
cost-effective

However, when cutting thick acrylic sheets, friction between the blade and material generates significant heat.

Water cooling is used only to remove heat caused by friction

This helps prevent:

melting edges
deformation
unstable cutting

CNC Machining (Above 80mm)

For thick acrylic blocks above 80mm, CNC machining is the preferred method.

Instead of cutting through in one pass, the process uses step cutting.

Example:

200mm thick acrylic sheet
machine 100mm from one side
flip the sheet
machine remaining 100mm

This method improves precision and reduces cutting resistance.

2. CNC Machining and Acrylic Fabrication

After rough cutting, CNC machining is used for detailed acrylic fabrication, including:

drilling
shaping
complex structures

Key Processing Tips

use proper acrylic cutting tools
control feed rate and spindle speed
avoid deep cuts in a single pass

Excessive cutting force increases friction and heat, which directly affects edge quality.

3. How to Polish Acrylic Sheets

After machining, edges are rough and need finishing.

Common Acrylic Polishing Methods

Flame Polishing

fast and efficient
suitable for simple edges

Mechanical Polishing

more consistent
better for standard products

Diamond Polishing

highest clarity
ideal for premium clear acrylic sheet applications

4. Common Problems in Thick Acrylic Processing

When processing thick plexiglass sheets, typical issues include:

overheating caused by friction
melted or rough edges
internal stress (can cause cracking later)
uneven polishing

The key is simple: control heat and keep the process stable

Why Material Quality Also Matters

Processing results don’t depend only on machines. The quality of the acrylic sheet itself also plays a big role.

For example, high-quality cast acrylic sheets like MASON® acrylic sheet tend to perform more consistently in cutting, CNC machining, and polishing. They offer:

more stable structure
better edge finish
reduced internal stress

This becomes especially important for thick acrylic fabrication projects.

Final Thoughts

Processing thick acrylic sheets (50mm–400mm) requires the right method:

cutting → control heat
CNC machining → control depth and speed
polishing → achieve final clarity

With proper processing and the right material, even very thick acrylic blocks can achieve clean edges and high-quality finishes.

For projects that require precision and consistency, working with a reliable acrylic sheet manufacturer and fabrication supplier can make a significant difference.

How to Process Thick Acrylic Sheets