How to Get the Most Accurate Injection Molding Quote

Getting a good quote for your plastic parts is key to budgeting and planning your project. But the accuracy and speed of that quote depends on the information you provide your supplier upfront.

By providing clear part details, project requirements and production expectations you enable your supplier to get a quote back to you quickly.

Follow this comprehensive guide to give your injection molder everything they need to get a quote for your parts.

Share Part Geometry

First step is to provide your supplier with detailed information about your part design. This includes:

CAD Files with All Dimensions and Tolerances

• Upload 2D drawings (PDF, DXF)
• Include 3D model files (STEP, IGES, STL)
• Show all dimensions, geometric tolerances, surface finishes, special features etc.

Complete 2D and 3D CAD models with all critical part dimensions are required for quoting. Upload native 2D drawings in common formats like PDF or DXF to get a clear visual. Also include 3D model files (STEP, IGES or STL formats) to show the full geometry.

The files should show all dimensions, diameters, widths, wall thicknesses etc. Notate any geometric dimensioning and tolerancing requirements showing acceptable size variations. Also specify surface finish requirements like maximum Ra values. Highlight any unique part features in the models – this includes drafted angles, fillets and rounds, ribs and bosses, inserts and holes, textured areas etc.

Complete CAD files give molders a deep understanding of the part design and allow for moldability analysis and identification of design for production. They can also determine the best mold configuration, feeding system and running parameters.ld configurations, feeding systems, and running parameters.

Physical Part Samples (If No CAD)

• Send molded parts, detailed images or rapid prototypes
• Annotate sample parts to define critical dimensions

If no CAD files are available, physical part samples can be sent but with more risk. Send molded prototypes or sample components to show the desired configuration. Mark critical dimensions on the parts with a marker if no drawings are available. This way at least the critical measurements can be extracted. Discuss any unclear areas with your molder.

No CAD, physical parts provide the detail for analysis and measurement.

send them high resolution photos of every angle and face of the components. Take pictures top down, side, front and back.

Use labels, arrows, text callouts and other annotations directly on the images to show key dimensions that would otherwise be unclear. For example, annotate a top view picture with length and width values, a side view with height and depth values, and a close up of a hole with size and location.

Include a scale in the photos so size can be measured. Providing dimensioned photographic documentation with physical parts helps a lot with manufacturability assessment when no complete CAD models are available.

Material Specification

• Specify plastic resin type (ABS, PC, nylon, PP, PE…)
• Define grade required (impact strength, heat resistance, fire retardant, glass fabric etc.)
• Consult supplier if unsure about the material

The resin material affects the molding behavior and final part cost. Providing this upfront avoids delays later due to material questions.

Part Quantity

• Total production volume
• Runs under 10,000 usually have higher per-part cost

Suppliers can optimize the mold design and production process for your specific volume when provided early.

Clearly Define Project Requirements

In addition to part parameters you need to communicate key project requirements:

Production Schedule

• Deadline for delivery
• Intermediate milestones

So we can plan the entire tooling and production flow.

• Use existing mold
• Custom mold features required

This affects mold design, machining, quality checks and other preparation procedures.

Secondary Operations

• Surface treatments (polishing, texturing, coating)
• Part assembly or installation
• Product packaging requirements

Quote these value added services upfront to avoid extra costs later.

Keep the Communication Open

Quoting smoothly requires clear and continuous communication:

Provide Part and Project Details

• Describe the part application and functionality
• Highlight high risk or complex features

Don’t assume the injection molder will understand the full context, use case and functionality of your plastic part components. Even if you provide complete technical drawings, many application details and operating conditions will be unclear or subject to wrong assumptions without you explaining it to them.

Provide detailed descriptions of the real world application and operating conditions of your parts. Share specifics like chemical or temperature exposure levels, mechanical cycling frequency and type, assembly configurations, diagrams or flowcharts if helpful. Explain key functional aspects – e.g. if a plastic enclosure must hold precise components in precise locations or if a ratio must withstand certain pressures without distortion.

Highlight high risk or complex geometries and share your risk mitigation strategy for these areas. Point out very thin or thick sections and ask for manufacturability guidance if concerned. Identify mating components and explain expected clearances or alignment requirements to reduce interfacing issues. Ask for material or design alternatives for difficult geometries if you want to consider options.

Sharing context helps the molder to understand where problems could occur and recommend solutions upfront. This prevents false assumptions that can mess up the quoting. Encourage your supplier to ask questions as well.

Ask to Clarify Any Doubts

• Ask for material guidance
• Ask for production feasibility for complex geometries
• Ask for equipment capabilities

Don’t be shy to ask. Suppliers should explain capabilities and limitations and offer recommendations.

Respond to All Information Requests Promptly

• Provide more data when asked
• Approve quote/feedback quickly

Respond quickly to avoid quote delays.

Choose a Qualified Injection Molder

A supplier with experience is key to quoting accurately:

Proven History of Manufacturing Similar Parts

• Look for expertise in your resin, volume, part size etc.
• Review case studies for similar projects

Experience in molding and processing parts like yours gives you confidence in the quote.

A supplier who is quality focused and has happy customers will get the production requirements right.

Good Customer Service and Communication

• Confirm fast response to questions
• Verify clear information provided
• Check for project updates

An injection molder who communicates clearly and proactively can quote accurately based on full understanding of your requirements.

Get Quoted for Injection Molding Quickly

Quoting injection molded parts quickly and accurately requires you to provide full part data and define your requirements upfront.

Open communication also allows the supplier to fully understand your application and project requirements when evaluating manufacturability.

In the end, choosing a highly qualified injection molder with experience in manufacturing similar parts gives you confidence in the quote you can use for budgeting.

Follow these tips to get quoted for injection molding quickly and accurately. Contact us if you have more questions!

Step	Description
1. Design Specifications	Provide details about your part design, materials, finishes, etc.
2. Quote Review	Review and approve the design and quote for costs.
3. Mold Design	Our engineers design the mold based on your specifications.
4. Mold Manufacturing	The mold is manufactured to precise specifications.
5. Mold Sampling	Initial plastic parts are sampled from the mold for approval.
6. Production	Full production manufacturing runs to create your parts.
7. Quality Inspection	Stringent quality checks ensure parts meet requirements.
8. Part Shipping	Completed parts are shipped directly to your facility.

The table summarizes the 8 key steps in injection molding quoting and manufacturing process