Injection molding is a standard industrial method; plastic injection parts exporter produces the vast majority of plastic items today. Traditional CNC machined metal molds have prohibitively high prices and long lead times for low-volume manufacturing, despite being the best process for large-scale production demands. 3D printed injection plastic molds are a time and cost-saving alternative for prototype and low-volume manufacturing (about 10-1000 components). They also allow for a more agile production strategy, allowing engineers and designers to test mold designs, readily tweak them, and then iterate on their ideas considerably faster than traditional CNC machining. Using a stereolithography (SLA) 3D printer, such as the Form 3+, to create bespoke molds is straightforward and convenient, allowing you to reap the benefits of both 3D printing and traditional molding processes. In this article, we’ll walk you through the plastic injection parts process and give you all the equipment and techniques you’ll need to use plastic injection parts in-house using 3D printed molds.
What You Need for plastic Injection Molding
Building a plastic molding system does take some expenditure. They are acquiring and mastering the proper equipment costs both money and effort. However, these fees are often less than the cost of a single metal mold, so the time and money saved once you’re up and running will easily justify the initial work.
To get started, you’ll need the following:
Form labs’ Form 3+ is a high-performance desktop SLA 3D printer. The Form 3+ can produce precise molds with sharp features and a clean surface finish, producing high-quality final molded products. Aside from plastic molding, an SLA 3D printer is also helpful for prototyping and other uses during product development.
A 3D printing material that can endure the mold’s temperature and pressure during the injection molding. For Form labs SLA 3D printers, we propose the following materials:
Rigid 10K Resin is an industrial-grade, highly glass-filled material that can handle various geometries and injection molding processes. It is vital, very stiff, and thermally stable, with an HDT of 218°C @ 0.45 MPa and a tensile modulus of 10,000 MPa.
High Temp Resin is appropriate for injection molding and has a heat deflection temperature of 238 °C @ 0.45 MPa. This material is brittle, yet it is ideal for materials with a high molding temperature and to shorten the cooling time.
Grey Pro Resin has lesser heat conductivity than High Temp Resin or Rigid Resin, so it takes longer to cool, but it is softer and can withstand hundreds of cycles.
A tabletop injection molder, such as the Golomb Model-B100 or the Holi press. Benchtop injection molders are available in a variety of price ranges. Many low-cost molders employ a hand-driven plunger, although other higher-priced ones use a screw or pneumatic system. Some of our clients have also recommended Minijector, Morgan, APSX, or Micro molder solutions. Desktop automated molders, such as the Babyplast product series, are viable options for mass manufacturing tiny parts.
Your choice of plastic pellets.
To create the mold, insert, and use your preferred CAD software, such as Blender.
Before purchasing, thoroughly compare the injection molder to your production needs. Industrial techniques are still need for significant components. This plastic injection parts process is best suit for creating tiny parts in limited quantities.
Plastic Injection Parts Step by Step
Design the Mold in CAD
To begin, select your preferred CAD software program for designing the mold insert. The open-source Blender will be used, although the procedure should be equivalent to any other CAD software. You will utilize the blank mold insert design files to develop your injection mold design. The designs are also scaled and able to fit most injection molders and mold frames. Alternatively, you can use the cavity schematics of the master mold frames to construct your mold insert.
Toggle off one side of the mold in Blender by clicking the eye symbol in the scene explorer. Set both sides of the mold to the “wire” draw type under the Object menu after your workspace is configured to your preference. You may now place your mold. During the injection molding, ensure that the item ultimately connects with the molten plastic intake. To make this easier, activate orthographic mode using “toggle perspective/ortho.”
Please turn off the visibility of your current mold core and turn it back on. Repeat the operation until the item completely intersects the entrance of the second half of the mold core. After you’ve aligned your objects, use Blender’s “Boolean difference” function to remove the area of two overlapping things. Pick the Boolean option from the Modifiers Menu after selecting the first part of your item. Make sure the “difference” action is chosen for your cutting object. Apply the operator and repeat on the opposite side. Your mold is now prepared for printing. Export each half, and check the “Selection Only” box in the Blender exporter.
3D Print the Mold
It is critical to use a material that can handle the temperature and pressure on the mold during the injection molding process when 3D printing the mold. Based on internal testing and client case studies, we recommend selecting the 3D printing resin based on the parameters. Three stars indicate that the resin is highly effective, whereas one star suggests it is less effective.
Injection Molding the Plastic Parts
You can mold the pieces on your benchtop plastic injection parts machine now that you’ve created and 3D printed your mold.
For injection molding, you have a vast range of materials to pick from:
Before making your decision, consider the required qualities of your product as well as the capabilities of your injection molder. Simply follow the customized instructions on your injection molder to make your components fast and efficiently. Depending on the injected material, component adherence to the mold might cause mold damage during extraction, especially with flexible materials like TPUs or TPEs. A mold release agent is a suitable approach to detach the component from the mold.