Plastic overmolding

What is plastic injection overmolding?

Overmolding refers to a mold in which two plastic materials are injected on the same injection molding machine and molded in two times, but the product is only released once. Generally, this molding process is also called two-component injection molding, which is usually completed by a set of molds and requires a special two-color injection molding machine. Overmoldings are increasingly popular in the market. This process can make the appearance of the product more beautiful, and it is easy to change colors without spraying, but it has high requirements for design and injection molding.

Injection molding service

Wintech is a plastic injection molding service provider, we are committed to building an incubation base for plastic parts. We provide complete manufacturing solutions, including component design tooling, production and finishing of parts, final inspection, and more. Our dedicated manufacturing team is dedicated to providing the highest level of professional support to our customers, consult us on plastic injection molding of any size or complexity.

Product information:

Mold Tool Materials

We make plastic injection molding tools and dies from S136H, 2316H, H13, 2316H, P20, 8407 (hardened) and NAK80 (hardened). Additionally, we offer standard SPI finishes, EDM texturing and a range of etched textures.

Each of these material types will have distinct advantages for certain applications. Considerations include:

Cost of the raw material

Durability and resistance to corrosion or abrasion

Machinability

Ability to take a high surface polish

Time required for heat treatment

Expected tool life

Contact our technical specialists to learn more about which one is right for you.

Mold-building standard includes:

Mold Steel: ASSAB(Sweden), DAIDO(Japan), FINKL(America), AUBERT&DUVAL(France), Schmolz-bickenbach(Germany)，LKM(China)

Mold Base: DME, HASCO, FUTABA, LKM or equivalent.

Hot Runner: MOULD MASTER, Master TIP, HUSKY, HASCO, DMEYUDO, INCOE, THERMOPLAY.

Standard Parts: DME, HASCO, MISUMI, NEAREST ANSI STANDARD, NEAREST DIN STANDARD, LKM.

Texture: Mould-tech, YickSang, Tanazawa VDI, Eschmann etc.

Plastic Injected Part Materials

There are thousands of thermoforming and thermosetting plastics to choose from for your project. In addition, mechanical and chemical characteristics can also be enhanced with additives like glass fibers, UV stabilizers and lubricants. Our materials sheet will give you more detailed information about the standard types and the tolerances to expect with each.

Your choice of resins may depend upon one or more of the following considerations:

UV, chemical, abrasion and impact resistance

Cost of raw material

Mechanical strength

Weight and density

Flexibility

Transparency

Recyclability

Molding Tolerances

Molding tolerance is a specified allowance on the deviation in parameters such as dimensions, weights, shapes, or angles, etc. To maximise control in setting tolerances there is usually a minimum and maximum limit on thickness, based on the process used. Injection molding typically is capable of tolerances equivalent to an IT Grade of about 9–14. The possible tolerance of a thermoplastic or a thermoset is ±0.008 to ±0.002 inches. In specialised applications tolerances as low as ±5 µm on both diameters and linear features are achieved in mass production. Surface finishes of 0.0500 to 0.1000 µm or better can be obtained. Rough or pebbled surfaces are also possible.

All plastic material will expand and contract under the influence of heat and moisture. Our tolerance guide will give more general information on the characteristics of most common resin types for typical part features.

We will work closely with you to optimize your designs for manufacturing. We will indicate any areas where poor design may produce thermal stress, shrinkage, warping, etc. Consult our design guide for more information on common defects and how to avoid them.

Advantages to Wintech’s Moldmaking Service

When you choose Wintech for quick turnaround mold tools, you get a host of services to support any project, including:

Design For Manufacturing

Our Design for Manufacturing review identified areas of the CAD model that could cause molding defects, so that’s always our first priority to address. We also find that at this level of detail we can offer the customer opportunities to make minor improvements that they may have overlooked, so now is a great time to implement them.

We worked with the customer to understand critical tolerances or other dimensions that could not be modified and then worked within those constraints. We then prepared a powerpoint file to share with the client, highlighting the most important areas for their feedback.