Impossible to Possible: A Micro Molding Case Study

When a large medical equipment manufacturer was searching for a micro-molding alternative to an inefficient process, the word “no” came up in every vendor conversation. That is, until they found their “yes” provided by one supplier.
 
The Challenge
The medical OEM had designed a thin wall, micro molded, plastic part with a fairly long flow length for use as a component in a drug delivery system. The vendor manufacturing the part used an extrusion and forming process that resulted in some defective products and a fair amount of fallout.
 
In order to improve yield, quality, and cost efficiency, the OEM decided to explore other options. It believed micro molding would provide the desired outcome, but the manufacturers they contacted said it simply couldn’t be done.
 
One vendor finally suggested the medical equipment manufacturer speak with MTD, a micro medical component manufacturer. Familiar with the firm’s reputation, the vendor assumed MTD would offer a solution to the micro component project. Reluctantly, the OEM decided to try one more supplier and found that perseverance paid off.
 
The Solution
The first priority for MTD was to prove the thin wall micro component could be successfully fabricated. During a facility tour, the OEM viewed high-aspect-ratio part samples that were built via thin wall micro molding. This demonstrated the ability to produce results that were similar to the customer’s desired geometry.
 

A number of factors led to the project’s success as the part moved through the process.
 
Precise tooling execution along with a slight design change made the difference.
At a project’s onset, customers participate in a design review process that covers all considerations before finally arriving at a solution that meets the product’s needs, while concurrently, maximizing manufacturability.
 
Sometimes, even a seemingly minor change to a design can have a significant impact on manufacturing and a project’s success. For example, this project involved adding draft within the original tolerance to release the micro component from the mold.
 
Presenting alternative materials contributed to the project’s success.
Similar to changes in design, exploring options for thin wall molding materials can boost a project’s chances for manufacturing success. When the customer requested a specific type of material for the part, MTD presented alternatives that would provide the same properties while improving manufacturability.
 
Before a project begins, a process failure mode and effects analysis (PFMEA) is performed to create contingency plans with regard to material, design, and tooling. For example, the material this customer preferred turned out to be less advantageous for the micro component molding process. As a result of the early discussion regarding alternative materials, MTD was able to quickly switch to a more appropriate material and move the project forward, uninterrupted.
 
The End Result
MTD was able to achieve the customer’s key goals, including higher yield, better quality, and lower costs. Being told “no” so often had almost led the OEM to believe they had unrealistic expectations. In essence, they had received false negatives and inaccurate claims that the part couldn’t be made. A false negative can kill a program or cause a company to needlessly compromise on design.
 
Due to these false negatives, the customer was initially skeptical of MTD’s assurance that the thin wall micro molded part could be successfully manufactured. But as the project unfolded, they realized the manufacturing efficiency they needed while keeping costs under control could be achieved.