Injection Molding Request for Quotation Checklist

Are you searching for sources to provide injection molding components on new or existing projects? Sourcing plastic parts is a serious process for OEMS around the globe, especially when dealing with critical parts for automotive or aerospace applications. Approving new suppliers takes time and effort, which makes it beneficial to seek out the injection molders and mold makers that are registered to ISO9001 and AS9100.

Molders that adhere to a strict quality policy, with documented proof of continual improvement, make the supplier approval process a little easier. Once you determine your sources, you’re ready to submit your requests for proposals. Quality minded injection molders have a process for determining project cost estimates and knowing what to include with your initial request for quotation is helpful.

Be prepared to provide the following information for a thorough and accurate injection molding quote:


1   Do you need a cost estimate for the injection mold and production molding?

Transfer Tool

If this is an existing project with a transfer tool, there will be additional questions regarding where and how the tool was built and if there are any molding problems that cannot be resolved. Usually, when transferring a tool, it is due to quality issues or molding problems at the existing molder, onshoring molds bringing production back to the U.S. for various reasons, or simply a cost-based decision. The state of the existing mold may affect the cost of ongoing production if there are design and engineering changes necessary to produce quality product.

New Mold Design

If you require a new injection mold, there will be further information needed to design the mold, including a part design or sample part, estimated annual usage, plastic resin material used for molding, secondary operations required and any special quality inspection procedures for critical dimensions.

2   Are there CAD drawings, part prints or sample parts?

Provide all three if you have them. A detailed part design is necessary to provide an accurate new tool design. Any critical dimensions or areas of interest, such as thin walls, should be clearly identified.

The type of press the tool will run in, the clamping system and ejection system required are important considerations when designing an injection mold, along with the type of resin used for molding.

Detailed part prints should include all this information, which is helpful to the mold designer and injection molding technician.

3   Provide all information on the polymer resin chosen for injection molding.

A mold designer must know the type of resin used for many reasons including shrink rate and wear and tear on the tool. For example, a glass-filled nylon will require special consideration when determining the type of steel used and for planning the preventive maintenance schedule.

The size of the part and the cost of the resin make up most of the material cost. Some specialty materials can be quite expensive, especially projects that require imported materials. If the tool is a cold runner design with runners (sprues), the weight of the runner must be included as added material cost. A hot runner tool will save on material over a high-volume production project.

Any allowance of regrind material should be considered, and the possibility of a substitution material can be explored if additional properties are desired. The resin chosen is of high consideration when quoting the injection mold design and the production molding cost estimate.

4   What is the estimated annual usage and part functionality?

The annual usage of the part or parts quoted is necessary to provide an accurate quote. A price break is typical with increased annual usage, especially for products that do not require a lot of secondary operations. There is usually a price break on raw materials based on quantity purchased so the material required to support the usage is necessary information.

Too often we are given all this information, except for the part functionality. Knowing how the part is expected to hold up in its functional role is helpful information to provide the best advice from skilled injection molding specialists.

In essence, the more information the better, but gathering all of this data upfront will be helpful to obtaining the most accurate quotation on injection mold builds and process injection molding.

QT Manufacturing Provides Thorough Injection Molding Quotations

QT Manufacturing is a custom injection mold designer, mold builder and injection molding processing company. We are registered to ISO9001:2015 and AS9100D, providing only the highest level of quality and service to all customers. We partner with you from the beginning to provide quality product molded to your specification, on time and at the lowest possible cost to you. Our continual improvement operations keep your costs low with quality minded processes.

for a FREE design consultation and to learn how we can reduce your injection molded component expenses.