PCB Assembly Graphic

Case Studies

Micro Molding Requiring Material Specification And Simulation

Prototype mold


The Challenge

A client approached us because they had not received acceptable parts with other prototype molding vendors. Issues included accuracy and surface finish of the 0.013” wide “teeth” features. We have extensive experience with micro-molding and molded similarly challenging features in the past, so we quoted mold fabrication and molding. There were three keys to success on this project: material selection, molding simulation and mold fabrication.

3D Model of a Prototype Injection Mold

Material Selection

When we started Protoshop we wanted to provide a more complete customer solution than existing prototype molders. We found that other service providers assume that the customer has extensive experience in plastic part design and material selection. However, from our experience in medical product development, we knew that it takes many years and dozens of projects to achieve even basic proficiency in plastic design and material selection. Therefore, we created Protoshop with the goal that we are going to provide plastic part design and material selection assistance to better ensure that our customers yield parts that are going to be successful in their application.

In this case, the customer needed the “teeth” features to be very rigid yet would not easily fracture. We selected polycarbonate to be a good choice for this application. Polycarbonate is rigid yet does not easily fracture which meets their mechanical requirements. The shrinkage of polycarbonate is consistent and predictable, so it was a good choice for the accuracy requirements. There were two concerns about the use of polycarbonate. The first concern is that most grades of polycarbonate do not flow sufficiently to fill the “teeth” features. This was addressed by selecting a unique grade of polycarbonate with a high melt flow. The second concern was the high flow polycarbonate specification sheet which indicated the rigidity of the material would fall short of requirements. To address this concern, we had a small batch of high flow polycarbonate quickly compounded with 10% glass beads. The glass beads add substantial rigidity to the material and the low fill percentage did not significantly affect flow performance. With the material selected it was then time to proceed with molding simulation.

Rainbow 3D Model of Prototype Injection Molded Part

Molding Simulation

Solidworks offers an add-on software called “Plastics” which allows us to accurately simulate cavity filling during molding after entering a few key parameters such as the material, gate location, gate size, temperature and injection parameters. Protoshop has invested in a seat of this software to better ensure successful parts for our clients. The purpose of this software is to utilize the molding simulation on plastic parts which include features or materials that we anticipate could have potential for issues such as incomplete fill, trapped air, part warping, sink, etc. We can experiment with changing features such gate location, gate geometry and wall thicknesses to determine which yields optimal results. A thorough analysis can be completed in less than an hour. In this case the goal of the molding simulation is to confirm that the use of high flow polycarbonate with 10% glass bead fill is capable to fully filling the “teeth” features.

We entered the material parameters into the software and ran the simulation. Results are shown in the image above which indicates the temperature profile of the part at the end of the fill. The “teeth” features would not appear complete if the simulation did not show sufficient pressure to fill the features. Therefore, this simulation confirmed our expectation that we would successfully fill this part with the careful selection of high flow polycarbonate as the base material. We proceeded with prototype mold design and fabrication.

Mold Fabrication and Molding

It’s the skill and experience of our master machinists that sets us apart. Over thousands of prototype molds, we were able to accomplish the smooth and accurate surfaces on the “teeth” required by the client that other prototype molders were unable to achieve. We use high quality Arburg injection molding machines which is a critical tool towards molding consistent parts. Also, unlike most prototype molders, our molds include both heating and cooling which allows us to mold parts that more closely replicate production quality parts. After molding, parts were tested in our Inspection Lab. All “teeth” and gaps between were measured to be within the 0.0005” tolerance. This mold was designed, fabricated, and molded in just two days. Our client was pleased with the results and gave us the following compliment that was so clever that we had to share it.

“I was an atheist my whole life but when Protoshop started on our project I was forced to believe in a higher power. They are true Gods of molding”.

Based on 7 reviews
Dana Taylor
Dana Taylor
If you're in need of a molding prototype shop, Dylann and Jimmy at Protoshop are sure to not only meet but exceed your expectations. Their team demonstrates remarkable responsiveness and proactiveness, contributing to an exceptionally efficient overall process. The speed at which they deliver top-notch work is truly impressive. Protoshop's commitment to customer satisfaction is apparent in their flexibility and willingness to closely collaborate with clients to address specific needs. An exemplary instance of this was their accommodation of our request to have our customer onsite for part evaluation and mold changes while we were present. What sets Protoshop apart is not solely their technical proficiency but also their dedication to providing valuable insights and design advice. Their expertise extends beyond standard projects, showcasing proficiency in handling complex components for diverse applications, be it over-molded sealing parts or flexible components. In conclusion, if you're on the lookout for a reliable and efficient partner for your manufacturing and molding requirements, I wholeheartedly recommend Protoshop. Their combination of expertise, responsiveness, and commitment to customer satisfaction makes them an exceptional choice for a variety of projects.
Brittany Mason
Brittany Mason
I have worked with Photoshop on several mold designs over the past year. From the moment I reached out to them with an inquiry, they were prompt in their communication and eager to assist me. I have greatly appreciated and benefited from their extensive expertise and prompt feedback. They consistently offering valuable suggestions and insights that ultimately saved us money in the overall design. As for the quality of work they provided, Dylann and her team have always come through. If any issues do arise, they have been quick to offer solutions and kept us up to date throughout the whole process. If you're looking for a reliable partner for your plastics molding needs, I would check them out.
Stacie Depner
Stacie Depner
Having worked with Dylann and Jimmy prior to Protoshop, I knew the immense level of expertise they have for this business and it proved to carry through. They are honest straight shooters that will help guide you and find the best solution for your molds. We needed a mild that could be versatile and allow us to easily change out one side of the design. Dylann helped us come up with an approach that will allow us to continuously iteration the design without having to make a whole new mold every time.
Chad Follmar
Chad Follmar
Dylann and team are wonderful to work with. On multiple programs, they have delivered quality product in a matter of days. The design for moldability support is unparalled to ensure your part is ready to order.
Garrett Garner
Garrett Garner
We work regularly with Protoshop on a variety of complex components for various projects. They are an excellent company to work with providing a vast history of experience to help their clients optimize designs. We have worked with them on microfluidic chips with small feature sizes, over molded sealing parts and flexible parts. They have experience working with many materials including Topas (COC), polycarbonate, TPE, PE, and PP. I would highly recommend reaching out on your next project. The team is very responsive to design changes as well as delivering to tight timelines. They also offer design advice and best practices which have helped expedite design iterations.
Steven Soeder
Steven Soeder
Great experience with Protoshop. Dylann is extremely responsive and great to work with. Very fast turn-around. Worked with us on our order to get what we needed. I was able to drop ship 3d printed parts from another vendor to Protoshop to have them match-fit and incorporated into our tooling. I will be back again.
Wendell Woidyla
Wendell Woidyla
Dylann at Protoshop is excellent to work with: highly responsive and proactive. This is possibly the fastest, high-quality work I have ever witnessed. 1 week...from payment (start) to delivery (after CTQ measurements at Protoshop), we had 100 test samples of a component we intend to use in high volume manufacturing. Thank you for the tremendous work! I would highly recommend Protoshop, and will plan to use Protoshop services in the future.