As a leader in the injection mold industry, Abtec Inc. professionals realize that every project is unique and oriented to the special requirements of our clients. In this regard, our staff of engineers, designers, and fabricators enjoy the challenge of custom injection molded designs that necessitate precision engineering. Since Abtec Inc. has equipment to meet the requirements of any injection molding design, we can take a client’s vision and convert it into a reality, regardless of how it is presented.
Initial Design Stage of Custom Injection Molding
The initial stages of Abtec Inc. custom designs begins with a dialog between our highly trained professionals and our clients and partners. Regardless of the knowledge level of a client, we are able to carefully listen to their vision and offer suggestions, guidance, and methods as to making their vision a precision fabricated product. Abtec Inc. takes pride in being able to help our clients and partners achieve their goals using our technical capabilities, industry experience, and professional skills.
The engineers and designers at Abtec Inc. use the data, dimensions, and vision presented by a client and create a computer rendering using Computer Aided Design (CAD) software. The rendering is presented to the client for their examination and allows ABTEC engineers to adjust, change, and add features that may not have been considered during the initial presentation. CAD software makes it possible to present each step of the manufacturing process using the computer rendering.
Considerations When Creating a Custom Design
The CAD design follows the parameters of the injection molding process. Although nearly every form of part, component, piece, or intricate design can be created using injection molding, there are certain parameters to the design process that have to be closely adhered to for the injection molding process to be successful.
The engineering of the CAD rendering provides fabricators with the dimensions and shape of the desired component. The computer-generated design is adjusted, oriented, and changed in accordance with the requirements of the injection molding process. In the initial stages of the design process, there are certain features that should be avoided.
Undercuts
Undercuts are recessed areas that are inaccessible using a straight tool. In injection molding, undercuts make it difficult to eject a part from a one-piece mold and are indentations or protrusions in the desired shape. They increase the complexity of a shape and the cost of the tooling of the ejection mechanism. Although undercuts make injection molding difficult, they can be engineered into a mold but require the manufacturing of a unique mold with a specially designed parting line, the part of a mold where the two halves meet.
Wall Thickness
As may be expected, wall thickness is an important part of injection mold design since it determines the strength and durability of a part. The walls of a design should be even, smooth, and uniform to prevent sinks and voids. Thin wall custom injection molding is normally used for mass production of thin and light weight parts with short cycle times. Thick walls are necessary when a part will be weight bearing and ribs may buckle under a load. Cycle times for thick-walled parts are longer, and material costs are higher.
Draft
Draft is a taper on the face of a mold at an angle that is applied to vertical walls. They assist in the ejection of a part from its mold. Draft is a required feature of custom injection molded parts. The functional aspect of a part necessitates a draft angle that faces the cavity and core sides to reduce the risk of damage to the completed part during ejection. The minimum draft angle is 0.5o up to 5o for faces.
Ribs
Ribs are thin wall features that are designed into a part for additional support for the walls of a part and are used to avoid increasing wall thickness. They are commonly used with thin-walled parts that could be damaged by wear and are normally less than 60% of the wall thickness. They are thinner than the walls to avoid exceptionally thick sections in a wall. Although ribs and gussets may be added to a part, the draft angle of the walls is maintained.
Bosses
Bosses are aspects of injection molded parts that assist in assemblies and are receptacles for screws or threaded inserts and can be locators for mating pins. They have to be strong enough to be able to hold an assembly together and have a minimum size to ensure their strength. Bosses should be at 30% of the wall thickness with a 30% edge groove. They are normally attached to ribs, gussets, or side walls for easy access.
Finishing
Another component of custom injection molding is designing the finish of a part or component. Finishes for injection molding are achieved during the molding process and are part of the CAD design. Injection mold finishes are outlined by Plastic Industry Association Standards, which is known as the SPI. The standards for injection molding finishes outlined by SPI includes the grades of finishes that run from A-1 up to D-3.
The Abtec Inc. Difference
Although injection molding is Abtec Inc. primary business, we go far beyond our plastic molding services and provide secondary operations that are combined with Abtec Inc. state of the art custom injection molding processes. Our secondary services include:
- Ultrasonic welding
- Milling
- Drilling and tapping
- Heat staking
- Painting
- Hot stamping
Reasons for Using Custom Injection Molding Services
- Customizability. Your tooling/mold will be custom-built for injection molding. Additionally, parts created this way can be easily colored using additives, creating aesthetically pleasing products.
- Cost-effectiveness. The automation utilized in the injection molding process significantly reduces overhead costs, allowing a sole operator to oversee the molding process.
- Accuracy. With a properly designed mold, the injection molding process can ensure tight tolerance accuracy molding to meet customer demand to print specifications.
- Efficient use of materials. The injection molding process reduces unnecessary plastic waste, as the material is injected directly into the mold during production.
- Easy reclamation and recycling. Any unused material can easily be melted down for reuse.
- Enhanced strength. Plastics have an incredibly high resistance to wear and can be injected with fillers during the molding process to create additional strength.
The Abtec Inc. Difference
With over 100 years of experience in design, development, and manufacturing, Abtec Inc. has the experience and know how to complete any project on time at a quality standard that is highest in the injection molding industry. Our dedication to our customer/partners is what has made us one of the most successful injection molding producers in the world. Our team of engineers and designers can take your drawings, sketches, models, parts, or existing mold and turn them into high quality molded Abtec Inc. custom parts.
Find us on line here or call today at 215-788-0950 to speak to an Abtec Inc. custom thermoplastic injection mold specialist.