Buyer's Guide: Selecting a Metal AM Service Bureau

Start with the part, not the machine

Most teams treat metal AM service bureaus as interchangeable. They submit a STEP file, wait for a quote, and hope the part works. This approach fails when the part is critical. A service bureau is only as good as its materials, process control, and ability to solve design problems.

The difference between a good provider and a bad one shows up in the first production run. A bad provider sends a part with visible surface roughness, inconsistent dimensions, or a missing heat treat certificate. A good provider flags a design flaw before the build starts and documents the fix.

Before you sign a contract, define what the part needs to do. Is it a prototype for a design freeze? A production run of one hundred units? A small batch of custom tooling? The answer changes which provider is the right fit.

Define your material and machine requirements

Metal AM uses several processes. Laser powder bed fusion is common for structural parts. Electron beam melting suits reactive metals like titanium and tantalum. Direct metal laser sintering handles some powders that LBF does not support well. Ask your provider which process fits your material.

Laser powder bed fusion uses a high power laser to melt metal powder in layers. It produces strong, dense parts suitable for aerospace and medical use. Electron beam melting operates in a vacuum and handles reactive metals without a gas shield. Direct metal laser sintering uses a lower energy laser and is often used for tooling and decorative parts.

Check the powder source. Reputable bureaus use certified powder from major suppliers. Ask for the mill test certificate and the lot traceability. If the powder is recycled, ask how many recycles it has gone through and what the particle size distribution looks like. Recycled powder can work, but it changes the process parameters.

Do not assume every bureau can run every alloy. Some machines are tuned for 17-4 PH stainless. Others specialize in Inconel 718. Others focus on Ti-6Al-4V. Ask for a list of materials they have built in the last year. If they cannot name the alloy, they are likely not the right partner.

Evaluate design support and DfAM

A service bureau that only prints files is a commodity. A service bureau that designs with you is a partner. Before you select a provider, check their design for additive manufacturing capability.

Many parts designed for CNC machining have features that are difficult or impossible to print. Overhangs, thin walls, and tight internal channels cause failure in PBF. A good provider will review your CAD model and suggest changes. They may move a bolt hole to a different location. They may add a support structure that reduces post-processing. They may thicken a wall that is too thin to melt correctly.

Ask for a DfAM review as part of the quote. Some bureaus do this for free. Others charge an hourly rate. Either way, it is worth the cost. A small design change can reduce part weight by twenty percent and cut build time in half.

Check their experience with your part type. If you are building a turbine blade, look for a provider with aerospace experience. If you are building a medical implant, look for a provider with biocompatibility experience. If you are building a custom tooling insert, look for a provider with high volume tooling experience.

Check quality control and inspection

Quality control is where service bureaus separate themselves. Ask for their inspection protocols. Most reputable providers perform dimensional checks with CMM or optical scanners. Some use X-ray CT scanning to check internal porosity. Others use ultrasonic testing for critical parts.

Ask what acceptance criteria they use. For aerospace, they may follow ASTM or EN standards. For medical, they may follow ISO 13485. For automotive, they may follow IATF 16949. If they do not follow any standard, ask why.

Request a sample report. A good provider will send a PDF report with part dimensions, surface roughness, and material certification. A bad provider will send a photo and a “looks good” email.

Also check their post-processing. Many metal AM parts need heat treatment, machining, or surface finishing. Ask what their standard post-processing workflow is. Do they in-house heat treatment? Do they outsource machining? If they outsource, ask who. A provider that controls the entire process has less risk of damage or loss.

Compare cost and logistics

Cost is not the only factor, but it matters. Ask for a quote that includes design review, build, post-processing, and shipping. Do not accept a quote that only covers the build time.

Build time is one cost driver. Material is another. Some alloys are expensive. Titanium costs more than steel. Inconel costs more than titanium. If you are using an expensive material, ask if the provider has a bulk discount.

Shipping is a hidden cost. Metal AM parts are heavy and sometimes fragile. Ask about packaging. A good provider will use protective foam or a custom crate. A bad provider will wrap the part in bubble wrap and ship it in a cardboard box.

Ask about lead time. A part that takes three weeks to build may take six weeks to deliver. If you need the part by a specific date, ask for a realistic timeline. Do not accept a quote that promises delivery in two weeks if the build alone takes three.

Use a criteria table to compare providers

Use the table below to score each provider. Give each criterion a weight based on your project. A part for a medical device may weight QC higher than a part for a custom tooling insert. A prototype may weight design support higher than a production run.

Criterion	What to look for	Why it matters
Material traceability	Mill test certificates, powder lot numbers, alloy certifications	Ensures the part meets spec and is safe for critical use
Machine capability	List of alloys built, machine type, power rating	Confirms they can build your part without compromise
Design support	DfAM review, revision history, communication channel	Catches flaws early and reduces rework
QC protocols	Inspection method, acceptance criteria, sample report	Verifies the part meets dimensions and material spec
Post-processing	In-house vs outsourced, heat treat, machining, finishing	Controls quality from build to delivery
Lead time	Build time, post-processing time, shipping time	Matches your project deadline
Cost structure	Build cost, material cost, setup fee, shipping	Reveals total cost of ownership
Liability and IP	NDA terms, liability cap, data ownership	Protects your designs and limits financial risk

Score each provider from one to five. Multiply by the weight. The highest score wins. If two providers are close, run a small pilot.

Run a pilot before full production

Never jump straight to a full production run. Order a small batch. Ask for three to five parts. Use the same material, the same build orientation, and the same post-processing as the production run.

Inspect the pilot parts. Check dimensions with a caliper or CMM. Check surface finish. Check for porosity if you have access to X-ray. If the parts are good, proceed to production. If they are not, ask the provider to explain why and what they will fix.

A good provider will take responsibility for the failure. A bad provider will blame the design. If they blame the design, ask for a written explanation. If they cannot explain it, walk away.

The pilot also tests the communication. How fast do they reply to emails? Do they send updates without being asked? Do they flag problems early? These soft factors matter. A provider that keeps you informed is less risky than one that goes silent.

Check the contract terms

Before you sign, read the contract. Look for these terms:

1. Intellectual property. Your designs belong to you. The provider cannot use them for other customers.
2. Confidentiality. The provider must sign an NDA. Your data must be stored securely.
3. Liability. What happens if a part fails in the field? Does the provider cover the cost? Is there a cap?
4. Delivery. What is the penalty if they are late? What is the return policy if the part is defective?
5. Material. Who owns the material? If you supply the powder, who is responsible for storage and handling?
6. Data ownership. Who owns the build files and the inspection reports?

Do not accept a contract that says “as is” with no warranty. A good provider will stand behind their work. A bad provider will shift all risk to you.

If you are in a regulated industry, ask for their quality system. Medical devices need ISO 13485. Aerospace needs AS9100. Automotive needs IATF 16949. If they do not have the certification, ask if they plan to get it.

Decision checklist

Use this checklist before you sign the contract.

1. We have verified the material spec and machine capability.
2. We have received a written DfAM review of our CAD model.
3. We have scored the provider using the criteria table.
4. We have ordered a pilot batch and inspected the parts.
5. We have reviewed the QC report and the material certificate.
6. We have read the contract and confirmed IP, liability, and NDA terms.
7. We have confirmed the lead time matches our project deadline.
8. We have confirmed the cost includes design, build, post-processing, and shipping.
9. We have a clear communication channel with a named account manager.
10. We are ready to proceed to production.

If you cannot check all ten boxes, do not sign. Fix the gaps. A good provider will help you fix them. A bad provider will try to rush you.

Selecting a metal AM service bureau is a strategic decision. The right provider becomes a long term partner. The wrong provider becomes a source of rework, delay, and risk. Use the criteria in this guide to make the selection. Start with the part, verify the capabilities, and run a pilot. Then sign.