How to RFI a Service Bureau for AM
To RFI a service bureau, define your part requirements first. Send a structured request covering materials, tolerances, and QC. Compare responses on lead time, traceability, and defect handling. Use a scorecard to select the right partner for outsourced AM work.
- Send a detailed RFI with part drawings, material specs, and quantity expectations before requesting quotes.
- Ask bureaus to confirm traceability, inspection methods, and defect handling procedures in writing.
- Verify lead time commitments against realistic process steps, including post-processing and heat treatment.
- Test communication speed and technical clarity during the RFI phase to predict future project support.
- Use a scoring matrix to compare bureaus on technical capability, QC documentation, and commercial flexibility.
Define the RFI scope before sending it
A service bureau cannot quote a part without a clear definition of what is being requested. The RFI is not just a request for pricing. It is a technical qualification exercise that tests the bureau’s process knowledge and quality culture.
Start with a single part or a small set of representative parts. Include the CAD file in neutral format, such as STEP or IGES. Specify the material grade, not just the family. For metal AM, list the exact alloy designation and heat treatment requirement. For polymer AM, state the resin or powder grade if the design depends on it.
Set the quantity. A bureau’s lead time for ten parts differs from a lead time for ten thousand. Include target tolerances, surface finish requirements, and any secondary operations like machining or coating. If the part is safety-critical, state that explicitly. The RFI should force the bureau to engage with the real constraints of the program.
Build a structured RFI template
A generic email asking for a quote will produce a generic response. A structured template produces comparable data. Keep the RFI short enough that an engineering manager can answer it in one sitting.
Use these sections in the template:
- Part and drawing reference. Provide the CAD file and a drawing with GD&T where applicable.
- Material and process. State the preferred material and process. Ask the bureau to confirm availability or suggest an equivalent.
- Quantity and schedule. State the required quantity and target delivery date.
- Tolerances and finish. List critical dimensions, surface finish, and any special surface treatments.
- Quality requirements. State which standards apply, such as ISO or ASTM, and which inspection reports are needed.
- Traceability and documentation. Request a lot number, heat treatment certificate, and dimensional inspection report.
- Defect handling. Ask how the bureau handles rejected parts and rework.
- Commercial terms. Request unit pricing, lead time, and tooling or setup fees if any.
This structure makes it easy to compare responses. Each bureau will answer in its own voice, but the data points will be consistent.
Send the RFI to at least three bureaus
Do not send the RFI to only one bureau. The first response is a baseline, not a comparison. Send the same RFI to at least three service bureaus with overlapping capabilities. Choose bureaus that demonstrate experience with your material and process.
When sending the RFI, attach the CAD file and a short note. State that you are evaluating partners for a recurring program. This signals seriousness without committing to a purchase. Ask for a response within five to seven business days. A long response time is a data point in itself.
Send the RFI to the technical contact, not just sales. A sales engineer who understands process parameters will answer differently from a generalist who copies a template. Ask for the name and title of the person who will review the technical details.
Evaluate the technical response
Read the technical response for specificity. A strong response will reference the exact process parameters, such as laser power, scan strategy, or build orientation. It will explain why the build orientation was chosen. It will identify potential risk areas, such as overhangs, thin walls, or stress concentrations.
Check the tolerance commitment. Some bureaus quote a generic tolerance like plus or minus 0.1 mm. Ask for the tolerance on critical dimensions only. If the bureau cannot commit, ask what inspection method they use and what the actual variation is. A vague tolerance commitment is a red flag.
Look for post-processing details. Metal AM parts often require support removal, heat treatment, and machining. A good bureau will explain each step and its impact on lead time. If the bureau does not mention post-processing, ask directly. The missing step is where the lead time hides.
Compare QC and traceability documentation
Quality documentation separates a mature bureau from a casual printer. Ask for a sample quality package for a previous part of similar complexity. This should include a dimensional inspection report, material certificate, and heat treatment log. For polymer AM, ask for a material data sheet and a resin lot number.
Traceability is non-negotiable for production parts. The bureau should be able to trace the final part back to the raw material lot, the build lot, and the post-processing batch. If the bureau cannot provide this chain, the risk of a quality incident is high.
Ask about non-destructive testing. For metal AM, ask which NDT methods are available, such as X-ray or ultrasonic testing. For polymer AM, ask about dimensional stability testing if the part is subject to heat or moisture. The bureau should be able to explain when each method is used and what it detects.
Check the defect handling process
Every AM part has a defect. The question is how the bureau manages it. Ask for a written defect handling procedure. This should cover how a defect is identified, who is notified, what the customer approval is, and what the cost is for rework or replacement.
A mature bureau will have a clear process. They will not blame the customer for a defect that the process created. They will not hide a defect in the final inspection report. They will document the defect, assess the impact, and offer a corrective action.
If the bureau has no written procedure, ask how they handle a rejected part in practice. If the answer is vague, move on. A bureau that cannot explain how it handles failure will not handle it well when it happens.
Build a scoring matrix
Do not rely on gut feel. Build a simple scoring matrix with the following categories:
| Category | Weight | What to score |
|---|---|---|
| Technical capability | 30% | Process parameters, material availability, tolerance commitment |
| Quality and QC | 25% | Inspection reports, traceability, NDT availability, defect process |
| Lead time and schedule | 20% | Realistic timeline, post-processing clarity, on-time history |
| Communication | 15% | Response speed, clarity of answers, technical depth |
| Commercial terms | 10% | Pricing structure, flexibility, contract terms |
Score each bureau from one to five in each category. Multiply by the weight. The highest score is the recommended partner, but a bureau that scores low in quality or communication should be disqualified regardless of price.
Make the final selection
The selection is a risk decision, not just a price decision. A lower price with a weak QC process is expensive. A higher price with a strong traceability chain and clear defect handling is a safer investment.
Choose the bureau that answers the RFI with the most technical detail. Choose the bureau that identifies risks before you ask. Choose the bureau that provides a clear path from CAD to finished part. The RFI is a filter. It removes weak candidates and highlights the ones worth a first small order.
Place a small trial order with the selected bureau. Use the trial order to verify the quality package, the lead time, and the communication. The RFI is the first step. The trial order is the second. Do not skip either.
Common mistakes in RFIing a service bureau
The most common mistake is sending a vague RFI. A request for a quote without material, tolerance, or quantity data produces a generic quote. The second mistake is comparing only price. Price is one factor, not the only factor.
The third mistake is skipping the traceability question. A bureau that cannot show a material lot number or a build lot number is not ready for production work. The fourth mistake is accepting a lead time without asking about post-processing. The lead time that excludes heat treatment and machining is not the real lead time.
The fifth mistake is not testing communication. If the RFI response is slow, vague, or full of template language, the project support will be slow, vague, and full of template language. The RFI is a communication test. Pass it or do not proceed.
Final verification step
Before placing the order, send a final verification email to the selected bureau. Confirm the part number, material grade, quantity, tolerance, and delivery date in one email. Ask the bureau to reply with a signed purchase order or a written confirmation.
This step prevents scope creep. It creates a shared understanding. It gives both parties a document to refer to if a dispute arises. It is the last step in the RFI process, but it is the step that turns a quote into a contract. Do not skip it.
Frequently asked questions
How many service bureaus should I contact in an RFI?
Contact at least three bureaus with overlapping capabilities. This gives you a meaningful comparison and reduces the risk of being locked into a single supplier.
What CAD format should I use in the RFI?
Use a neutral format like STEP or IGES. These formats are widely supported and reduce the chance of file corruption or version conflicts during the review process.
Do I need to specify the exact material grade in the RFI?
Yes. Specify the exact alloy or resin grade, not just the family. The grade determines the mechanical properties, heat treatment, and cost. A vague material request leads to a generic quote.
How should I handle a bureau that does not respond to the RFI?
Wait seven business days before following up once. If there is no response after the follow-up, remove the bureau from the shortlist. A slow response is a reliable indicator of project support quality.
Is a small trial order necessary after the RFI?
Yes. A small trial order verifies the quality package, lead time, and communication under real conditions. The RFI is a paper exercise. The trial order is the proof.
