If you are looking to hire a prototype molder there are several key features that you should look for as you compare molding partners that are critical to the success of your project.
1. Mold temperature control
To cut time and cost, many prototype molders will not include temperature control on the mold. However, temperature control is critical to achieving part accuracy and consistency in a manner that replicates production molding. You should ask your molder if their prototype molds include temperature control and only use a supplier that uses a molding system that includes it.
2. Rapid mold iterations
The ability for your molder to implement quick changes to your prototype mold is extremely important for product development. Your company is losing money every day that your product is not on the market. Unfortunately, many prototype molders aren’t set up to provide quick mold changes so it is important to ask their procedure for requesting mold changes and how long those changes typically take to implement. Select a prototype molder that can implement mold changes within 2-3 days.
3. Part design assistance
Plastic part design is relatively difficult where rules change with geometry and materials. It takes years over several projects to gain even a minimal competency with plastic part design. Many molders won’t provide any assistance at all. Others will point out where there are issues but won’t help to resolve them. Look for a prototype molder that is willing to meet with you via online conference to understand your application, step through any issues with you and offer options to resolve them. A prototype molder that offers design assistance to refine your part will significantly improve your chances of success. This will reduce the number of iterations required and minimize the time it takes to bring your product to market.
4. Material selection assistance
Like plastic part design, it can take years of experience and exposure to a wide variety of materials before a person becomes proficient at specifying materials for injection molding. There are more than 100 different material types and over 30,000 grades of injection moldable materials available. There are also dozens of additives available that can be used to enhance certain material properties. Select a prototype molder that can help you navigate these extensive material options and recommend materials that will meet your needs. The molder should also explain exactly why the recommended material is the best option.
5. Accepts complex or challenging geometry
Too often, prototype molders reject complex geometry or challenging molds such as insert and over molding. If you find that a prototype molder is rejecting these types of molds it should be taken as a sign that you need a new vendor. Many prototype molders have systems in place that are not compatible with more complex parts. Your prototype molder should have a system that allows for flexibility and a wide variety of simple to complex parts.
Your prototype molder should work with you to create a drawing of your part that indicates critical dimensions and tolerances. Unfortunately, many prototype molders do not follow this important step. Without a drawing it is undefined which features are critical to part function and what tolerance is acceptable. Knowing which features are important and their tolerance allows the molder to ensure your parts meet your functional needs. Only use prototype molders that both accept drawings and can provide a drawing for you, then use the drawing to ensure you receive parts that are going to meet your needs.
7. Inspection services
Your prototype molder should perform a first article inspection of critical dimensions when a mold is first completed. The data should confirm that all dimensions are within acceptance criteria. Also, this inspection should be in-house at the prototype molder rather than using a third party. The prototype molder should be in the practice of checking their work and have a policy that they do not release molded parts until they have been proven to be acceptable. Unfortunately, many prototype molders do not perform first article inspection and therefore do not confirm that parts are accurate.
8. Flexible material options
Look for a prototype molder that offers a variety of material options. Prototype molders should 1) have a wide variety of materials readily available in stock, 2) allow customers to submit their own materials for use, and 3) coordinate material orders from distributors and custom compounders on behalf of their customers. All material options should be available.
9. Transferrable prototype molds
A prototype mold should be transferable. There is critical learning that can occur when the mold is transferred to the contract manufacturer that may then be applied to the production mold. In addition, the contract manufacturer can use the prototype molds to run large quantities of parts which can assist in establishing manufacturing lines and support testing. Select a prototype molder that offers transferrable molds.
10. Bridge tooling
Prototype molds should be usable as bridge tooling. Bridge tooling means that the molds can be used to provide at least 50,000 ea parts to support development and may be used to support early production for projects that need to go to market quickly. Many prototype molders will offer various levels of mold fabrication with increasing cost and lead time. Look for a prototype molder with a molding system that is capable of molding a few parts to over 50,000 parts without increasing cost and lead time.
Protoshop was founded by product development engineers that have engaged various prototype molders in the past as a customer and always found their services to be lacking in several areas. We knew there was a way to provide better service. Protoshop was created to provide all of the key features indicated by this article that are lacking in our competitors. Our goal is to provide superior injection molded parts that exceed product requirements and customer expectations. High quality parts enable products to transfer to manufacturing with unrivaled speed and efficiency.