Design for injection moulding

Design for plastic injection moulding requires a certain approach and working with Rutland Plastics saves time and money and results in suitable plastic moulding designs from the outset.

Why use expensive external design services?

Here at Rutland Plastics we work in partnership from initial concept, through the injection moulding design stage using 3D CAD, to the making of the injection mould tool. All through that process, we share our expertise with customers and together we optimise the choice of plastic material, physical shape, ease of production, cost and performance.

We advocate that you take the opportunity to tap into this technical support early in the design process because it helps de-risk the project thus avoiding costlier modifications at a later stage.

Working in partnership

We believe in working in partnership with you, acting as an extension of your own technical department. Working together we can find the best injection moulding solution.

Free advice

In addition to the wealth of information freely available on our website, you can call us at anytime for help with your project.

Deliver on promise

We listen to what you want and work with you to achieve the results you need. Most of all it means delivering on our promise to you – every time.


There are many things to consider when designing for injection moulding. That’s why our experts are here to help.

Rutland Plastics uses Moldex3D software to fine tune new mould designs, therefore, ensuring cost effective and reliable designs from the outset.


Prototypes can also be arranged. Rutland Plastics has its own 3D printer capable of producing rapid plastic prototypes which will closely resemble the final injection moulded parts enabling you to fully test the part prior to investing in tooling.

Design guidelines

Taking your design through to production requires the part to undergo ‘Design for Manufacture’. The following series of articles offers help and advice in a number of areas.

Moldex3D MFA Software

Whenever designing a product or component for injection moulding, there is always a benefit in optimising the mould tool design and moulding process from the outset. Rutland Plastics’ technical team take pride in the support they offer customers. To help them they use Moldex3D MFA Software which enables the simulation of the injection moulding process to help develop cost effective and reliable mould designs; it can also help to assess optimum moulding conditions.

VISI Flow has been developed by Vero Software and sits alongside the VISI 3D design software and Machining Strategist that Rutland Plastics already uses.  The main advantages of VISI Flow are:

  • It is the first fully integrated CAD/CAE application
  • Provides accurate mould filling simulation
  • Identifies aesthetic issues
  • Predicts warping
  • Can help with design for gas assisted moulding, another service offered by Rutland Plastics


Visi Flow


The most obvious time to use this design aid is at the early stages of development. Before any tool design is started, using VISI Flow to analyse the design of the part can highlight any potential manufacturing issues, such as weld lines, air traps and the best gate location. This can avoid any costly and time consuming changes to the mould tool at a later date.


Of course, there are occasions when existing components are not moulding or performing as expected. VISI Flow simulations can help with understanding the conditions inside the mould cavity during the moulding cycle. This can save time and money in judging the effectiveness of different corrective actions whether that is to the moulding process or even minor modifications to the mould tool itself.


VISI Flow uses a patented ‘meshing’ approach to the 3D model which gives consistent results unaffected by component size, complexity or wall thickness.

Results are affected by the type and even the grade of material used.  There is an extensive material database covering a wide selection of material grades and suppliers.  The software provides the same level of control over the injection of molten polymer into the mould tool as on any injection moulding machine.  The filling simulation provides the ability to forecast and visualise how a part will be filled making it possible to identify any potential aesthetic issues.  The results will also help identify any possible defects, such as sinking or voids.  If necessary, it is possible to export the warped model geometry for comparison with the original CAD data for potential reverse engineering or improvements to the mould tool design.

Rutland Plastics can work with CAD files in almost any format although Parasolid or STEP are the preferred options.  Contact Rutland Plastics for help with your products or components, whether it is a completely new project or existing parts that you may be experiencing problems with.


We can provide advice and quotes on anything from a simple sketch to a 3D computer model. Most drawing formats can be handled although we find STEP, Parasolid and DXF translate most successfully.