Plastic Fabrication, Cutting and Moulding: What are my options?
There is an extremely large variety of plastic fabrication methods available, with each process offering distinct advantages and disadvantages. Choosing the right method depends on the products you require and on their size. The important thing is that no matter what product you need, whether that is acrylic cut to size or larger high impact polystyrene sheet, there is a fabrication method suitable for you!
This article will give you a tour among the most popular and effective plastic fabrication, cutting, and moulding methods so you can make an informed decision and choose the one that will suit your needs best.
CNC stands for computerised numerical controlled. This refers to the automated control of machining tools and 3D printers through the use of a computer. Instead of a manual operator directly controlling the machining operation, a computer directs the process by following instructions from pre-programmed software and code. The instructions can be written by a person or generated by computer-aided design software (CAD).
This computerized manufacturing process involves a laser beam melting the material away creating a cut; the excess is then removed by a high-pressure gas.
Advantages of CNC laser cutting:
-Â Â Â Â Â Â Â Â Â Making it possible to cut different shapes;
-Â Â Â Â Â Â Â Â Â No need to exchange tools for different cuts;
-Â Â Â Â Â Â Â Â Â Easy to make intricate cuts;
-Â Â Â Â Â Â Â Â Â More accuracy compared to thermal cutting;
-Â Â Â Â Â Â Â Â Â Faster than traditional mechanical cutting methods;
-Â Â Â Â Â Â Â Â Â A highly automated process requiring little manpower.
Disadvantages of CNC laser cutting:
-Â Â Â Â Â Â Â Â Â It requires a high level of expertise;
-Â Â Â Â Â Â Â Â Â Limitations to plastic thickness;
-Â Â Â Â Â Â Â Â Â Large upfront costs;
-Â Â Â Â Â Â Â Â Â It emits dangerous gas and fumes.
CNC laser cutting can be used with the majority of plastic variants, including harder plastics like acrylic. Typical applications of CNC plastic laser cutting are creative designs and signage, but the method is also used to manufacture automotive parts and plumbing.
A CNC router is a pre-programmed, computerised machine used for cutting various materials, such as steel, aluminium, foam, wood, composites, and plastic. The equipment uses computerised numerical control to route tool paths and manufactures a wide variety of items faster and with less waste.
Like the previous method, CNC router cutting also uses pre-programmed commands. Designs are created using CAD software, they are next converted to G-code, and eventually the CNC software runs the G-code that delivers instructions to the machine.
Advantages of CNC router cutting
-Â Â Â Â Â Â Â Â Â Making precision cuts;
-Â Â Â Â Â Â Â Â Â Not requiring human control and supervision;
-Â Â Â Â Â Â Â Â Â Multiple safety features to reduce accident risk;
-Â Â Â Â Â Â Â Â Â A CNC router is easy to update.
Disadvantages of CNC router cutting
-Â Â Â Â Â Â Â Â Â Large upfront costs;
-Â Â Â Â Â Â Â Â Â Decreasing the demand for manual machine operators;
-Â Â Â Â Â Â Â Â Â Creating a skills gap in the manufacturing industry.
Items created with a CNC router are used as advertising signs, for crafts and arts, and for moulds and prototypes.
CNC water jet cutting is one of the most versatile processes for shape cutting. It can be used for cutting virtually any material. This technique allows you to obtain a variety of products, including Perspex cut to size, all with a smooth, precise cut surface.
The water jet cutting process needs an intensifier pump that creates ultra-high pressure so it can cut through a variety of materials.
Advantages of CNC water jet cutting
-Â Â Â Â Â Â Â Â Â Provides the highest precision cutting;
-Â Â Â Â Â Â Â Â Â Can be combined with plasma or oxy-fuel on the same part;
-Â Â Â Â Â Â Â Â Â Produces high tolerance parts with fine contours;
-Â Â Â Â Â Â Â Â Â No heat affected zones, no melted plastic;
-Â Â Â Â Â Â Â Â Â Lack of hazardous fumes and vapours;
-Â Â Â Â Â Â Â Â Â Environmentally safe as no airborne dust is produced.
Disadvantages of CNC water jet cutting
-Â Â Â Â Â Â Â Â Â Not suitable for brittle material like tempered glass or certain types of ceramics;
-Â Â Â Â Â Â Â Â Â Is slower and more expensive than other techniques.
This method has been used to produce parts for the automotive, medical and aerospace industries.
Thermo forming is a technique for moulding plastic to obtain versatile products. There are two types of thermo forming: vacuum forming and pressure forming.
It all starts with high density polyethylene a high impact polystyrene sheet that is heated to make it easy to manipulate. When the sheet reaches a certain temperature, it is formed over a mould. The next step is cooling the new form, followed by trimming in order to increase usability.
Advantages of thermo forming
-         Adaptability to customer’s design needs;
-Â Â Â Â Â Â Â Â Â Fast, which makes it suitable for building prototypes;
-Â Â Â Â Â Â Â Â Â Low production costs;
-Â Â Â Â Â Â Â Â Â Final results are very aesthetically pleasing.
Disadvantages of thermo forming
-Â Â Â Â Â Â Â Â Â This method is limited to thin-walled parts;
-Â Â Â Â Â Â Â Â Â The complexity of shapes it can be used to create has certain limitations;
-Â Â Â Â Â Â Â Â Â The need for trimming lengthens production times;
-Â Â Â Â Â Â Â Â Â It creates scrap plastic (which is recycled by most manufacturing companies).
The range of uses for thermo forming is very wide: rigid packaging for consumer goods, toys, plastic bins, and other products obtained from sheets.
CNC vacuum forming is a plastic manufacturing process consisting of heating a plastic sheet such as high density polyethylene and forming it into a shaped vacuum forming tool. The plastic sheet is cooled until it becomes hard and the part can be removed from the tool.
The procedure is relatively simple and can be used with a wide range of thermoplastic materials, such as acrylic, high impact acrylic, high impact styrene, polyethylene, polypropylene, and others.
Advantages of CNC vacuum forming
-Â Â Â Â Â Â Â Â Â The process is very fast and versatile;
-Â Â Â Â Â Â Â Â Â Allows you to obtain a variety of 3D objects;
-Â Â Â Â Â Â Â Â Â Suitable for short run production;
-Â Â Â Â Â Â Â Â Â Low manufacturing costs;
-Â Â Â Â Â Â Â Â Â Consistent shapes and sizes from batch to batch;
-Â Â Â Â Â Â Â Â Â Easy to scale production up or down.
Disadvantages of CNC vacuum forming
-Â Â Â Â Â Â Â Â Â Only one part of product can be made at a time;
-Â Â Â Â Â Â Â Â Â The need of additional costs and resources to finish components;
-Â Â Â Â Â Â Â Â Â The number of details you can achieve with this technique is limited;
-Â Â Â Â Â Â Â Â Â Prone to errors such as unwanted bubbles due to excess moisture or debris from the mould imprinted on clear or light-coloured parts.
CNC vacuum forming applications are similar to products obtained through thermo forming.
2D laser engraving is a technique enabling you to change the surface of an object using a laser beam. It is mostly used to create images on the surface of an object. 2D laser engraving is mostly used on acrylic materials.
The laser creates high heat that vaporizes matter and exposes cavities that form the desired image or text. A vectored file of the desired image or text is required from the client in order to produce the 2D engraving.
Advantages of 2D laser engraving
-Â Â Â Â Â Â Â Â Â Can be used to engrave small objects;
-Â Â Â Â Â Â Â Â Â The risk of damaging or deforming the material is low;
-Â Â Â Â Â Â Â Â Â High precision;
-Â Â Â Â Â Â Â Â Â The process does not include toxic solvents or inks;
-Â Â Â Â Â Â Â Â Â Markings are not affected by time and tear.
Disadvantages of 2D laser engraving
-Â Â Â Â Â Â Â Â Â Can be used for two-dimensional objects only;
-Â Â Â Â Â Â Â Â Â Cannot be used for deep carving;
-Â Â Â Â Â Â Â Â Â Not suitable for very hard materials or materials with a low ignition point.
The method is used for medical devices, fine art, and industrial applications.
3D laser engraving is used to create 3D engravings of photos and designs of various materials, including Perspex cut to size. Unlike 2D laser engraving, it also works on curved surfaces, creating distinct effects that were not possible to achieve in the past.
3D laser engraving can be described as burning away some parts of a materials surface in order to create depths for a great aesthetic finish.
Advantages of 3D laser engraving
-Â Â Â Â Â Â Â Â Â Superior to 2D laser engraving and being used more and more as the surface shape of industrial products is rarely plane;
-Â Â Â Â Â Â Â Â Â Suitable for deep carving;
-Â Â Â Â Â Â Â Â Â Allows for multi-colour engraving;
-Â Â Â Â Â Â Â Â Â High personalisation degrees;
Disadvantages of 3D laser engraving
-Â Â Â Â Â Â Â Â Â More time-consuming compared to traditional 2D engraving, so it requires more patience.
Applications are similar to that of 2D laser engraving, with the difference that objects with curved surfaces can be engraved.
Which combination of plastic fabrication, cutting, and moulding techniques suits your production and business needs the best? Plastic Online offers so much more than simply acrylic cut to size or standard plastic sheets. Plastic Online boasts two local factories, knowledgeable staff and a wide range of plastic products to fit all your requirements. Contact the premier Gold Coast plastic fabrication specialists Plastic Online today and discuss your custom plastic fabrication needs today.
