Rapid Prototyping UK: Prototype Manufacturer in Cambridge

Complete Fabrication Ltd (CompFab) is a prototype manufacturer in Whittlesford, Cambridge, making prototypes for UK product teams since 1986. We turn your CAD into accurate models and working parts by SLA, Carbon DLS and FDM 3D printing, CNC machining and vacuum casting, then paint, finish and assemble them in-house. SLA files received by 5:30 pm are usually printed that night and delivered the next day, when capacity allows. CNC machining takes 3 days, with a 24-hour rush option. We are ISO 9001 certified.

3D Systems Viper SLA machine running Accura Xtreme Grey resin
3D printing

SLA and 3D printed prototypes

Accurate parts for form, fit and design reviews. SLA, Carbon DLS, FDM and DLP, with a 24-hour standard turnaround and no rush fees. For tough thermoplastic parts, see FDM 3D printing.

Machining

CNC machined prototypes

Machined from solid aluminium, PEEK, stainless steel and engineering plastics, so your prototype has the strength of the production part. Most work is turned around in 3 days, with a 24-hour rush service if you need it.

CNC machined clear acrylic block with threaded internal channels
Rapid prototyping workshop benches with staff at work

Working prototypes

Looks-like, works-like models with inserts, assemblies and electronics fitted, ready for user trials, investor demos and design sign-off. See our model making services.

Finishing

Painting and finishing

Production-standard finishes on prototype parts: colour matched to Pantone, RAL or your sample, metallic and soft-touch coatings and VDI textures, from two in-house spray booths.

Node speaker gloss red paint finish
Blackfin mobile prototype painted with flexible rubber gasket
Seals

Flexible gaskets and seals

Silicone and polyurethane elastomer seals and gaskets cast to your specification, with moulds made in-house, so your prototype seals like the real thing.

Casting

Vacuum casting

Self-coloured polyurethane parts close to injection-moulded quality, in batches of 10 to 500. Lead time is confirmed at quote.

Silicone mould for vacuum casting polyurethane parts
Meridian speaker 7K production and paint finish
Advice

Not sure which process you need?

Only have technical drawings? We can turn them into CAD data, then recommend the fastest route to a good part. Our prototyping checklist covers the rest.

Design

Design development

We turn ideas into buildable CAD, with manufacture and assembly in mind, before the first prototype is made.

DRW SAMBA II diagnostic instrument with its white turret component
Vacuum-cast production part for an Owlstone breath analyser
Production

From prototype to production

Once the prototype is signed off, we make bridge production runs of 1 to 500+ units while your production tooling is being made. For printed runs, see SLA batch production.

Which prototyping process should you use?

A quick comparison of our main processes. We confirm the exact tolerance and lead time for your part when we quote.

ProcessTypical toleranceStandard turnaroundBest for
SLA 3D printing±0.15 mm24 hoursOne-offs to batches of thousands (our largest was 5,000 parts): detailed prototypes, master patterns and clear parts
Carbon DLSConfirmed at quoteConfirmed at quoteProduction-quality parts in tough, flexible and elastomer resins, in batches of up to 1,000 small parts
FDM 3D printing±0.4 mmDepends on part size and finishTough nylon, carbon-fibre and TPU parts
CNC machining±0.10 mm on most work3 days (24-hour rush available)Metal and engineering-plastic parts
Vacuum castingAbout ±0.2 mm on small parts, up to ±0.7 mm on large castingsAbout a week for 20 small parts; larger batches confirmed at quoteBatches of 10 to 500 self-coloured polyurethane parts
Our approach

Rapid prototyping and product development, with guidance at every stage

Prototyping can feel confusing. We give impartial, straightforward advice that simplifies each stage, and feed development information back to your team as if we were in-house. We work with product designers, design engineers, design consultancies and manufacturers across medical, robotics, aerospace and consumer products, and we are ISO 9001 certified.

pharmaCo inhaler prototype in SLA with packaging

24-hour SLA as standard

Most 3D printed parts ship the next day, and we quote fast.

Keurig coffee machine prototype with CNC machined parts

Tolerances that hold

SLA to ±0.15 mm and CNC to ±0.1 mm on most work, from the first prototype to production.

Owlstone breath tester product

Compliance built in

Certificates of Conformity for materials and manufacture, plus biocompatible options for patient-contact testing.

Results

Rapid prototyping case studies

A few of the prototypes we have built for medical, consumer and product design clients.

IPL hair removal device

A compact IPL hair removal device using LEDs instead of xenon flash lamps, plus its charging station. We produced 3D printed models so focus groups could test the ergonomics and design.

Read the IPL case study

Piona self-injector

A visual block model of an at-home fertility self-injector designed to look like a beauty product, showing its finishes, lighting effects and how it nests in the base.

Read the Piona case study

Working prototypes for Hayter

Two fully working lawn mower prototypes, one petrol and one electric, CNC machined in production-intent materials and painted in production colours. They cut grass.

Read the Hayter case study
Proven

Rapid prototyping since 1986

The work speaks for itself. These numbers show the scale, speed and consistency behind it.

zone dome for running unlimited working prototype

Projects completed

Thousands

From concept to production across multiple sectors

Industries served

20+

Medical, defence, robotics, aerospace, automotive, marine and consumer products, among others

Client retention rate

94%

Partners return because we deliver what matters

Get a rapid prototyping quote

Send us your CAD files and tell us your deadline. We quote fast and will do our best to match your timings. 3D printed parts can be on their way the next day.

Rapid prototyping: frequently asked questions

Which rapid prototyping processes do you offer?

We make prototypes by SLA, Carbon DLS and FDM 3D printing, CNC machining and vacuum casting, then paint, finish and assemble them in our Whittlesford workshop near Cambridge.

How fast can I get a prototype?

Standard SLA turnaround is 24 hours when capacity allows, and large parts need more planning. CNC machining is typically 3 days, with a 24-hour rush option. Painting or polishing adds at least a day. Vacuum casting 20 small parts takes about a week, and we confirm lead times for larger batches at quote.

How do I choose between SLA, Carbon DLS, CNC and vacuum casting?

Choose by quantity and purpose. SLA suits one to a few hundred parts while the design is changing. Vacuum casting suits 10 to 500 parts in production-like plastics. Carbon DLS suits small functional parts without tooling. CNC machining suits metal parts and tight tolerances.

What tolerances can you hold?

SLA parts hold ±0.15 mm. CNC machining holds ±0.10 mm on most work, and vacuum casting holds about ±0.2 mm on small parts and up to ±0.7 mm on large castings.

Do you work under NDA?

Yes. Confidentiality is standard, and we can build SOPs and technical agreements into the workflow.

How many parts can you make?

Anything from a single prototype to production batches. Our SLA batches are typically 20 to 200 parts, and the largest was 5,000. We have run Carbon DLS batches of 1,000 small parts, and vacuum casting covers 10 to 500. None of these needs injection-mould tooling.

Where are you based?

Our workshop is at Unit 4B Lion Works, Station Road East, Whittlesford, Cambridge CB22 4WL, just south of Cambridge near junction 10 of the M11. We make prototypes for clients across the UK.

Are you ISO certified?

Yes. We are ISO 9001 certified by ISOQAR under UKAS accreditation (certificate 7774). Certificates of Conformity for materials and manufacture are available on request at quote stage.

What is rapid prototyping?

Rapid prototyping is the quick making of physical models and working parts straight from CAD, so a design can be seen, handled and tested before money goes into production tooling. Most rapid prototypes are 3D printed, but CNC machining and vacuum casting are used when a part needs real materials or more copies.

Is rapid prototyping the same as 3D printing?

No. 3D printing is the most common rapid prototyping method, but not the only one. We also CNC machine prototypes in metals and engineering plastics, and vacuum cast batches of 10 to 500 in polyurethanes. The right method depends on the material, quantity and finish the part needs.

What are the benefits and limits of rapid prototyping?

It lets you find design problems, test fit and function, and show a product to users or investors before committing to tooling, while design changes are still cheap. The limits: a printed resin is not always the production material, and at hundreds or thousands of identical parts, injection moulding usually becomes cheaper per part.

How do I get a prototype made in the UK?

Send us your CAD (STEP is best) or drawings through our contact page, with the quantity, material or finish you need and your deadline. We check the design, recommend a process and send a quote. Once you accept, SLA parts are usually printed that night. If you only have sketches or drawings, we can create the CAD for you.