Short answer: The part’s weight does not tell you the price of the manufacturing route. Protolabs identifies machine time and finishing labor as important drivers in its metal-printing service. [1]
A small component can still require substantial engineering and finishing work. Before deciding that a quote is unreasonable, establish what the supplier is delivering.
Make the two quotations comparable
Quote A may cover a printed blank. Quote B may cover a finished component with agreed inspection records.
Ask both suppliers to quote the same scope:
| Item | Agreed RFQ requirement |
|---|---|
| Design | CAD and drawing revision |
| Material | Alloy and required delivered condition |
| Quantity | Prototype quantity and expected repeat orders |
| Geometry | Critical dimensions, datums and permitted changes |
| Finishing | Required surfaces, bores, threads and removal operations |
| Inspection | Methods, reporting scope and acceptance criteria |
| Documentation | Required material and manufacturing records |
| Timing | Delivery date for accepted components |
| Commercial scope | Shipping, taxes, rework and rejected-part responsibilities |
A useful comparison begins with a complete RFQ, not two headline prices.
A worked example: cheaper printing, dearer accepted parts
The following numbers are invented solely to demonstrate the calculation. They are not supplier prices or industry benchmarks.
Assume a development team funds all manufacturing and inspection work for ten trial components. It bears the cost of rejects.
| Trial cost | Route A | Route B |
|---|---|---|
| Printing | $1,200 | $1,600 |
| Post-processing | $600 | $300 |
| Inspection | $200 | $200 |
| Total trial spend | $2,000 | $2,100 |
| Accepted components | 8 | 10 |
| Spend per accepted component | $250 | $210 |
The calculation is total trial spend ÷ accepted components.
Route B costs more to print, but produces a lower spend per accepted component in this hypothetical trial. That does not prove it will remain better in production. A ten-part trial is a weak basis for predicting long-run yield.
If the supplier guarantees delivery of ten accepted parts for a fixed price, compare that contractual price instead. Do not add an assumed rejection charge that the buyer does not bear.
Ask for the cost driver before changing the design
Request one proposed change and its effect on total delivered price. Candidates for discussion include a different orientation, simpler finishing requirements on nonfunctional surfaces, or a conventional route.
Protolabs’ cost guidance illustrates that build height affects recoating time and that support-removal effort can influence route economics. [2] Your supplier must quantify those effects for your geometry.
Check proposed savings against the actual requirement. Removing a tolerance that nobody needs may help. Removing a tolerance required for assembly changes the product.
Give machining a fair comparison
A conventional route can be the right answer. Renishaw describes traditional manifold manufacture through machining, drilling and plugging before explaining the specific redesign opportunities for AM. [3]
Use the same functional requirements when comparing those routes. Include redesign and validation effort if changing the route creates that work.
Before selecting AM, write down the benefit you are buying: a geometry, an assembly change, a performance improvement or a supply advantage. Then ask what evidence shows that benefit is worth the delivered cost.
Your next supplier email
“Please quote the attached revision as a finished component against the stated acceptance requirements. Identify exclusions, separate one-time work from repeat-order pricing, and propose one design or route change that could reduce total delivered cost.”
That request gives the supplier something actionable and gives you a quotation you can evaluate.
Use Addithive’s Engineering Tools to test assumptions. Replace estimates with actual quotations before making the purchasing decision.
Sources
[1] Protolabs, Metal 3D Printing Service Cost Explained. Service-specific discussion of machine time, labor and finishing.
[2] Protolabs, The Cost of 3D Printing: Key Factors to Consider. Guidance on height, orientation and finishing effort.
[3] Renishaw, Hydraulic Block Manifold Redesign for Additive Manufacturing. Conventional baseline and an application-specific AM redesign.
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