Engineering-grade rapid prototyping

Accelerate innovation.
Rapid industrial prototyping.

We turn digital concepts into functional hardware — high-fidelity CNC machining, additive manufacturing and rapid tooling, with engineering feedback on every quote.

On the shop floor now
Rapid tooling lead time from 7 days
DFM feedback Within 24 hours
CNC tolerance ±0.005 mm
SLA accuracy ±0.1 mm
Batch size 1–10,000+ parts
How we work

You can see the part before it ships.

Configuration, inspection data and shipping status live in one place, and one engineer owns your project from quote to port.

PRJ-2418 / Ductile iron valve body / rev C Live
CAD model under design review Volume 450 cm³

Configuration & DFM

Optimised
MaterialDuctile iron GGG40
ProcessSand casting
FinishEpoxy coating
Unit priceQuoted in 24 h
Part under dimensional inspection ±0.05 mm

Inspection report

3 of 4 complete
  • Dimensional CMM report
  • Chemical composition
  • Hydrostatic pressure test
  • Final visual inspection
Packed parts ready for shipping

Production complete. Crates leave for Tianjin port this afternoon — tracking number follows tonight.

Shipping & contact

On schedule

Your project engineer

Replies within one working day
Production
Packing & export documents
In transit to port
Global supply

Foundry floor in Cangzhou, engineers in your timezone.

No middlemen between you and the machine

Our foundry roots and our export desk sit in the same company, so the person quoting your part can walk to the line it runs on. That is why pricing is direct and answers are specific.

  • CMM report with every shipment
  • Factory-direct pricing, no trading margin
  • Full material certification on request
Purnis manufacturing hub
CMM inspection in progress Quality verified

Start with a drawing, not a sales call

Send a STEP or IGES file and you will hear back from an engineer who has read it — with the DFM notes, the process we would pick, and a price.

Response time Under 24 hours
Direct email engineering@purnis.com
Upload CAD files
Engineering support team
Who we build for

Built for teams without a factory of their own.

Startups, studios and mid-sized machine builders get the same engineering attention as a volume account.

Hardware startups

Get a manufacturable design and a first batch without a purchasing department or a corporate account.

DFM guidanceFast iteration

Low-volume production

Production-grade parts in batches of 50 to 500, so you can test a market before committing to hard tooling.

No strict MOQBridge tooling

Engineering studios

Use us as your workshop: we handle fabrication and finishing while your team stays on design and testing.

NDA protectedHigh precision

Machine builders

Repeatable castings and machined components for mid-sized equipment lines, without carrying the overhead.

Consistent qualityAssembly ready
Engineering playbook

Problems R&D teams bring us, and what we do about them.

Three recent cases from global R&D teams. Pick one to see the engineering response.

JD

John D.

MedTech R&D lead

“My SLA prototypes look great, but the snap-fits shear off the moment we assemble them.”

SM

Sarah M.

Fluidics engineer

“Support removal scars the inside of our manifolds and we cannot reach in to polish them.”

RK

Robert K.

Hardware director

“Printing 200 parts is too slow, but a steel mould is $10k and four weeks away.”

New cases added every month
Case 01 Verified R&D enquiry
JD John D. says

“My SLA prototypes look great, but the snap-fits shear off immediately during assembly tests. We cannot validate the functional design.”

Our engineering response

Move functional features to moisture-conditioned SLS nylon

Standard resin is too brittle for cyclic fatigue. We reroute snap-fit components to our SLS (PA12) line and add a moisture-conditioning post-process that raises flexural toughness by about 30%, so the part behaves like injection-moulded POM or ABS during testing.

  • SLS PA12
  • Vacuum casting (ABS-like)