Acrylic is a very common plastic material you can find in many industries such as signage, boxes, jewelry, greenhouses, lenses, and many more. its lightweight, shatter-resistant, and high transparency make it popular in an array of applications. However, do you know how these products are produced? How to machine the acrylic? In this article, we will explore all the processes of machining acrylic.
Is Acrylic Easy to Machine?
Yes, acrylic is easy to machine and can be machined with different methods and tools such as cutting, bending, milling, turning, and more. Cast acrylic is generally easier to machined than extruded acrylic because Casting creates less internal stresses, so cast acrylic is less brittle than extruded acrylic.
Machining Acrylic pellets
When we talk about machining acrylic, actually there are two meanings. one is machining acrylic pellet material and one is machining acrylic sheet or block. this is because some of the machining process is working on acrylic sheet material.
Extrude Acrylic
Acrylic sheets are made by acrylic extrusion which is a process in which acrylic pellet material is pushed through a tool or die with specialized shape. and then these extruded acrylic sheets can be used for the second machining to create the final parts. some acrylic products with a fixed cross-sectional profile are also can be produced by this extrusion process, such as acrylic tubes, rods, films, etc.
Cast Acrylic
Acrylic sheets can also be made by casting. this process involves pouring the molten Acrylic pellets material into a mold, and cure for a few hours until it becomes semi-solid status, and then removing it from the mold, using heat and pressure to force air bubbles out of the acrylic sheet. these cast acrylic sheets can also be used for the second machining to create the final parts. As explained before, cast Acrylic sheets are generally easier to machine than extruded acrylic.
Injection molding Acrylic
Injection molding acrylic is a very common method to create large-scale acrylic products when the product shape is complex. this process uses an injection machine to inject molten acrylic pellet material into a mold with high pressure, and then the acrylic material cools and cures in the mold to form the final product. it creates acrylic products directly from the acrylic pellets.
Machining Acrylic Sheets/block
Raw acrylic sheets are typically manufactured in standard sizes and shapes. To create the final acrylic parts, other processes as below need to be used to machine the acrylic sheet.
Cut Acrylic sheet
Cutting acrylic to size as you need according to your product size, there are mainly four main methods to cut acrylic sheets.
- Score Acrylic sheet: Score the acrylic with a plastic scoring blade manually for a thin sheet.
- Saw cutting Acrylic sheet: you can use a table saw, jigsaw, or circular saw to cut thick acrylic sheets.
- CNC router cutting Acrylic: Using a CNC router, you can get a more precise dimension.
- Laser Cutting Acrylic: Use a laser beam to cut thin acrylic sheets when very high precision details are required.
Bending Acrylic sheet
Some products such as signage, stand are made by bending acrylic. An acrylic sheet can be bent by heating when heating to 160 degrees Celsius without discoloring the material. there are several ways to bend acrylic sheets.
- Bending Acrylic sheet With Heat Gun at home
- Bending acrylic sheet with a hairdryer at home
- Bending acrylic sheet with a bending machine(acrylic bender) to make a line bending
CNC Acrylic sheet
CNC acrylic sheet is widely used for CNC prototyping to make acrylic prototypes. CNC machining provides high precision and high quality as the injection molding parts, it can leverage the material’s unique properties, such as its clarity, UV stability, and impact resistance. Different CNC machining processes can be used for Acrylic sheets.
CNC milling Acrylic
One CNC process to shape acrylic sheets is to mill them. Milling is a process of removing material from the surface of the plastic sheet with high-speed rotated cutting tools. CNC milling acrylic creates acrylic parts with complex shapes such as optic light guides in automotive lighting.
CNC turning Acrylic
CNC turning acrylic uses a lathe where the acrylic block is rotated while a cutting tool is fed into it to remove the material. this process can produce cylindrical acrylic parts.
CNC drilling Acrylic
To drill holes in acrylic sheets, you also can use CNC drilling with a drill bit with a diameter to remove the material from the hole.
Single Point Diamond Turning acrylic
If you need a mirror finish on the acrylic with super high precision, a Diamond cutting machine is your best bet as the video shows, if you want to know more about this process, check out our blog about Diamond Turning: A Complete Guide.
Thermoforming Acrylic
Thermoforming Acrylic is mainly used as packaging for consumers and large customized products such as acrylic trays and acrylic boxes. It refers to the process of heating thin acrylic sheet material until it reaches a pliable temperature, then pushing the acrylic sheet into a mold to form a product shape. there are three kinds of thermoforming acrylic processes.
Drape Forming Acrylic
This process uses a Clamp to force the sheet against the mold, and then push the acrylic sheet into the mold. When the Acrylic sheet touches the mold, it will cool and then cease to stretch.
Pressure Forming Acrylic
This process uses air pressure from the top to form the acrylic sheet into a finely detailed molded shape. A pressure box is added to the tooling package.
Vacuum forming Acrylic
In this process, the parts are formed by the pressure of vacuum space between the mold and acrylic sheet it is widely used in creating numerous types of props and costume accessories.
Surface finishing on Acrylic Parts
Polishing Acrylic
Once after machining by CNC acrylic, Polishing is needed because the cutting tool will leave marks on the acrylic parts. Polishing will help remove any rough edges or scratches left. there are several polishing methods for acrylic parts.
- Hand polishing: use polishing paste and cotton cloth to work on acrylic parts manually.
- buffing wheel polishing: Use a Cloth buffing wheel and wax which is Great for DIY or at-home projects
- Flame polishing: utilizes a fine high-temperature flame which is based on hydrogen to polish acrylic.
- Diamond polishing: A specialty tooling is utilized to provide a polished finish using direct machine polishing.
Laser Engraving on Acrylic
Laser engraving on acrylic is commonly used for acrylic signs, innovative LED light displays, and unique ornaments with details on their surfaces. it uses CO2 lasers to burn and vaporize the needed area on the surface of acrylic to form the details.
Screen printing on Acrylic
Screen printing on Acrylic is a process to create markings or patterns on the surface of acrylic parts. it involves pushing ink through a mesh screen and onto an acrylic sheet, using a squeegee to fill the open apertures. After being exposed to UV light, the ink will dry and form the pattern.
Spray Painting and Dyeing Acrylic
Spray Painting and Dyeing Acrylic are used to add color to acrylic parts. Spray painting uses spray guns with air pressure to disperse into uniform and fine droplets and apply the painting to the surface of the object. Dyeing acrylic use a solution with dye and water to soak the acrylic part to leave the dye on the surface of the acrylic part.
Coating acrylic
This process is used to strengthen acrylic product performance with special types of coatings such as UV coating, hard coating, and anti-mist coating.
Conclusion
Machining acrylic is necessary if you want to create custom shapes and get the desired finish on your plastic products. it requires machines and skills, KUSLA is a one-stop manufacturing company that can help you with our acrylic machining Service.
FAQs
Can I cut acrylic myself?
Yes, with a plastic scoring blade and circular jaw, you can cut it at home with the right operations.
What machine do you use to cut acrylic?
A CNC router or a laser cut machine can be used to cut acrylic.
