Here is cash register or checkout counter bottom base Case Study we would like to present in this page. Creating a detailed case study on plastic injection molding parts for a Japanese customer is a task since they requires good price, fast lead time, high-quality output and excellent service. After the mold test , we got the oppotunity to communicate face to face with Japan’s customer to solve problem quickly.

Custom Plastic injection molds making & molding :

• Part Material: PA-MXD6-4511-BK
• Part Name：SUPERMAKRET CHECKOUT COUNTER BOTTOM BASE
• Shrinkage：1.0035
• Cavities: 1X1
• Size:43.9*133*258
• Tool Material: NAK80

Draft angles give necessary clearance between the tool wall and the adjacent part feature. More draft is better for easier Plastic Injection Molding mold release but there are limits so this needed to be discussed with the our Japanese client.

This customer from Japan invests hundreds USD to establish an overseas manufacturing company in the southern region of China.

They found JBR online and chose us as the right partner for the production of this Custom Plastic Injection Molding part after visiting our factory. We supported them in the feasibility study of the designed product, the production of the custom plastic injection molds as well as the parts. The proactive working method and in-depth technical expertise helped us make high-quality molds, that meets the excellent quality requirements of Japan’s customer setting for all its products. JBR continuously thought along in the whole mold degisn and making process,  to make sure fast delivery time and comply with all agreements.”

Design for Manufacturing Review

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 power point file to share with the client, highlighting the most important areas for their feedback.

Wall Thickness

It’s always a concern in custom plastic injection molding to use good design practices for wall thicknesses and related features. This is because the molten resin distributes heat throughout the entire custom plastic injection molded part, but areas that have an unequal distribution of heat will cool at different rates. This is one of the main causes of sink marks and other potential defects.

To locate potential sink marks we did a wall thickness analysis with Mold flow. It calculated those areas most likely to create sink due to unequal mass distribution. The areas marked in yellow show where a sink mark is likely to be, because there is an extra structure on the inside of the part that adds mass. In this case it’s unavoidable without a major re-design so the customer chose to accept the results.

Line of Draw and Parting Line

The line of draw is the direction in which the two halves of the plastic injection mold open and close. It defines how the molded part can be removed, and also shows where a parting line mark will be left over on the finished piece.
The direction of the tool opening not only affects the parting line but also the location and orientation of other components and features such as sliders and inserts, ejector pins and coolant lines.

Designing the Plastic Injectoin Mold Tool

Ejector Pins

Ejector pins push the part off the core after molding, but they leave a corresponding mark on the part surface. We had to be careful to place the pins in a balanced arrangement to ensure even distribution of force to avoid damaging the part or the pins themselves. We also needed to place pins strategically around the gate, where sufficient ejection pressure is needed to clear the gate in the event of a partial injection, or “short shot”.

Final Mold Tool Design

The final plastic injection mold assembly represented a careful orchestration of hundreds of separate components, all of those components intersected with circuits for coolant as well as the gates and runners for molten plastic.

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We hope that in this case study you were able to find useful information that can help you prepare your product designs for your next rapid prototyping or volume production order. We will apply the same careful Design for Manufacturing review when we help you bring your product ideas to life, so let’s get started today!