01763 249760  office@prototypeprojects.com

Learning Hub
Quote / Order
  • CNC Machining
    • CNC Turning
    • CNC Milling
    • CNC Low Volume Production
    • CNC Materials
    • CNC Finishing
    • Vapour Honing
    • CNC Machining 3-Day
    • Production Speeds
  • 3D Printing
    • SLS – Selective Laser Sintering
    • SLA – Stereolithography
    • MICRO 3D PRINTING
    • Polyjet 3D Printing
    • DLP – Digital Light Projection
    • Filament 3D Printing
    • SLS Dyeing
    • 3D Printing Materials
    • 3D Printing Finishing
    • Production Speeds
    • Additive Manufacturing
    • Additive Prototyping
    • Matrix
  • Vacuum Casting
  • Model Making
  • Expertise
    • Low Volume Manufacturing
    • Rapid Prototyping
    • Laser Cutting
    • Inspection
  • Downloads
    • Guides and whitepapers
    • Plant list
    • Policies, forms and certificates
    • Process datasheets
    • Prototype materials datasheets
  • About
    • Customers
    • Our Team
    • Our values
    • Payment methods
    • Work with us
    • News & Articles
    • Case Studies
    • Privacy statement
    • Sustainability
  • Contact
  1. Home
  2. Vacuum Casting
  3. Prototyping guide to Vacuum Casting 

Prototyping guide to Vacuum Casting 

What is Vacuum Casting? 

Vacuum casting is used to bridge the gap between 3D printed models and the production method, which is typically injection moulding. The moulds used to produce the parts are made from silicone rubber, the moulds have a limited life and are normally capable of producing 20-25 parts, though this is dependent on the polyurethane (PU) material being used. 

Did you know? 

Used in conjunction with other prototyping technologies, Vacuum Casting removes the requirement for expensive purpose made production tooling.

How does Vacuum Casting work? 

A master model (normally an SLA) is produced, then encapsulated in silicone rubber to create the mould (tool).  

Once the mould (tool) is completed and ready for use it is heated then placed in the chamber. The PU (A+B) resin is placed inside the upper chamber ready to be degassed and mixed. Once fully mixed, and the chamber has been evacuated, the PU resin is slowly released into the mould (tool). 

When enough resin is flowing into the tool, the vacuum is released, forcing the mixed resin to flow through the tool. Once the tool is filled with resin it is placed in an oven to cure for up to an hour. 

Once cured, the tool is removed from the oven and opened so the solid part can be removed. Finally, the part is finished by hand removing any flash and vent points. 

Did you know? 

The PU resin does not reach full material properties until seven days after it has been cured.

When should Vacuum Casting be used? 

Vacuum Casting is used for producing small numbers of polyurethane prototype parts with characteristics and quality comparable to the final product. 

The process can replicate patterns, dimensions, profiles and textures, and as such is widely used to produce parts for: 

  • functional testing such as thermal and air flow testing 
  • assembly line trials 
  • marketing purposes e.g. presentations and trade shows.

What are the benefits of Vacuum Casting? 

Vacuum Casting can deliver parts with varying degrees of flexibility or rigidity, in a wide range of materials and colours, including clear parts. It has several benefits: 

  • Low volume runs 
  • High quality 
  • Fine detail and accuracy 
  • Range of properties can be achieved to mimic the final product 
  • No requirement for expensive hard tooling. 

Technical information 

 Vacuum Casting Technical Details 

  • Maximum casting weight: 1400 g 
  • Maximum mould size: 450 x 470 x 400 mm

Vacuum Casting Part Properties 

  • Heat resistance 
  • Colours and tints 
  • Fire retardance 
  • Flexibility and rigidity 
  • UV stability
  • Range of surface finishes 
  • Insert options 
  • Water clear 
  • Flexible polyurethane casting resin grades range 
  • Inserts can be moulded in 
  • Range of finishes from grades of spark texture, smooth matt and satin to a high gloss finish. 

Plastic material simulation 

 Vacuum Cast parts produce material simulations of: 

  • ABS 
  • POM 
  • Elastomers (Range: 25 – 95 Shore A) 
  • Nylon including glass filled 
  • Polypropylene 

Vacuum Casting options 

Various finishing options are available for vacuum cast parts. These can be tailored, depending on the requirements of each project. 

The timescale for the production of multiple sets of vacuum cast parts will vary from project to project. Please speak to us about your next prototype project. 

Ready to start your next prototype project? 

Prototype Projects is a UK-based prototyping bureau delivering high quality prototype parts in fast turnaround times. 

As well as vacuum casting, we also deliver a range of 3D printing solutions with 4 dispatch options, including next day dispatch. We also offer a dyeing service for SLS prototype parts, as well as a texturing service for SLS and SLA parts. 

Contact us on 01763 249760 to discuss your next prototype project.

Recent Popular
The Benefits of Vacuum Casting for Low-Volume Production

The Benefits of Vacuum Casting for Low-Volume ...

6 May 2025 Comments Off on The Benefits of Vacuum Casting for Low-Volume Production
Understanding the Benefits of Vacuum Casting for Short Runs

Understanding the Benefits of Vacuum Casting for ...

2 May 2025 Comments Off on Understanding the Benefits of Vacuum Casting for Short Runs
SLA, Vacuum Casting, and Model Making - Versatile Prototyping Processes

SLA, Vacuum Casting, and Model Making – ...

30 April 2025 Comments Off on SLA, Vacuum Casting, and Model Making – Versatile Prototyping Processes
Overcoming a Tricky Build for Prototype Projects

Mini Door, Maximum Challenges: How Our Team ...

29 April 2025 Comments Off on Mini Door, Maximum Challenges: How Our Team Overcame a Tricky Build
CNC Prototyping to Production

CNC Prototyping to Production: Supporting Every Stage ...

22 April 2025 Comments Off on CNC Prototyping to Production: Supporting Every Stage of the Product Development Journey
James Dyson

Sir James Dyson: the man behind the ...

10 May 2019 0
Applications and design tips for SLS: a guide

Applications and design tips for SLS: a ...

27 November 2019 0
Prototyping medical devices for patient contact

Prototyping medical devices for patient contact

22 September 2021 0
silicone tooling

LUMA-iD develops Buddy with silicone tooling

21 July 2022 0
CNC Machining and CNC Turning

Understanding the Difference Between CNC Milling and ...

15 April 2025 Comments Off on Understanding the Difference Between CNC Milling and CNC Turning for Better Design Choices

Comments are closed

Next Day Dispatch

Delivering Overnight Printing

Email: office@prototypeprojects.com
Tel: 01763 249760

Prototype Projects Ltd
Units 1&2, Greenfield
Royston,
Herts SG8 5HN

If you have questions about any aspect of our service, please contact us.


    UKAS
    Cert no. 11512-QMS-001
    Cert no. 11512-EMS-001
    Made In Britain - Prototype Projects
    EHAAT proud supporter
    Royston Business Awards - Prototype Projects

    Sign up to our Company and Industry newsletter

    Sign up here

    Prototype Projects, established in 1980, is a specialist in the manufacture of prototypes. The company is experienced in 3D Printing, CNC Machining, Rapid Prototyping, Model Making and Additive Manufacturing. The company is located in Royston, Hertfordshire.

    Trustpilot - Prototype Projects

    About | Our team | Our values | Customers | Work with us

    CNC Machining

    CNC Turning
    CNC Milling
    CNC Materials
    CNC Finishing
    CNC Express
    Production Speeds

    3D Printing

    SLS
    SLA
    Micro 3D Printing
    Polyjet
    Digital Light Projection
    3D Printing Materials
    3D Printing Finishing
    Additive Manufacturing
    Additive Prototyping
    Production Speeds
    Matrix

    Expertise

    Low Volume Manufacturing
    Rapid Prototyping
    Laser Cutting
    Inspection

    Contact us

    Prototype Projects Ltd
    Units 1 &2, Greenfield
    Royston
    Herts SG8 5HN

    office@prototypeprojects.com
    T: 01763 249760

    © 2025 - Prototype Projects | Terms | Privacy | Web Design by Indigo Ross

    We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept All”, you consent to the use of ALL the cookies.
    However, you may visit Cookie Settingsto provide a controlled consent. Reject All
    ACCEPT ALL
    Manage consent

    Privacy Overview

    This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
    Necessary
    Always Enabled
    Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.
    CookieDurationDescription
    cookielawinfo-checkbox-analytics11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
    cookielawinfo-checkbox-functional11 monthsThe cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
    cookielawinfo-checkbox-necessary11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
    cookielawinfo-checkbox-others11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
    cookielawinfo-checkbox-performance11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
    viewed_cookie_policy11 monthsThe cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
    Functional
    Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.
    Performance
    Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
    Analytics
    Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.
    Advertisement
    Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.
    Others
    Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet.
    SAVE & ACCEPT