Product design guide

Successful products are those that manage to achieve a perfect balance of function, practicality and price, and that most importantly create resonance with the end user. Even with the most basic products there are many key design, factors to consider. The concepts below should be considered at every stage of the design process.


The most important thing about any product is that it does what it’s designed to do, and that it is easy to use, it doesn’t matter how great it looks, if it doesn’t work people won’t buy it. Think about the overall purpose of the product at every stage of the design process. Don’t lose sight of the end goal.


As frustrating and constraining as it can be, cost is a reality. Most designers can design an expensive all singing, all dancing product when budget is not an issue. Great designers will design products that do what they need to do whilst being affordable and simple to produce.


Understanding fully what the end users want is the key to designing a successful product. Researching the market that your product or idea is specifically designed for is key, having clarity of what existing products are currently available to do a similar job, their pros and cons and at what price point they are at is very important. The products that customers are likely to buy are those that are the most relevant to their needs, that add value and do the job that they are designed to do, efficiently and reliably.


Looks, although not always necessary, give your product the edge over the competition for the simple fact that people like things that look nice. Often looks go hand in hand with usability as a great product is always designed around how the product works. It’s important not to sacrifice other elements, in the name of beauty, as the product still has to function as it is was originally designed to do, or the customer will not buy it, and if they do certainly will not recommend it to anyone, if it does not function properly.

Go Green – Smart product design, process and materials don’t have to cost the Earth!!  Save bottom line costs while minimising environmental impact.

The materials, process and packaging of a new product are very important choices, ensuring that new products are designed to be produced and operate efficiently, that material choices have the lowest impact on the environment, and that they can be recycled when ever possible, this can lead to overall cost savings. The less product packaging you have, the lower overall product cost, also reducing the impact on the environment. Making products like plastic boxes for example, nest into each other efficiently, reducing their overall size when packed in volume, is a simple way to save on shipping and transport costs, while reducing environmental impact. Smart design, process and material choices can lead to significant cost savings, enhanced customer satisfaction along with much less impact on the environment, during the products’ life cycle. Below are some key questions that should be asked in the beginning of the product design process.

  • How much power does it take to produce with the chosen production process, and how much pollution? Is there a more efficient or alternative way make this product?
  • How durable is it? Is the product going to last to its designed life and not fail prematurely in real world working conditions?
  • How efficient is it? Can we make the product more efficient?
  • How long will it last? Will the product last to its designed life?
  • Can it be recycled? Can the product be recycled easily at the end of its life?
  • Can we make it smaller and lighter, using smart design with less materials while maintaining the desired strength and durability?
  • Does it need packaging or what is the minimum requirement? (think of an apple, not much packaging there!)

For minimal effort making smart design, production and material choices for new products can lead to overall cost savings, enhanced customer satisfaction and reduced impact on the environment.



If you achieve all of the above items then you will have designed a product that really resonates with the end user. After all, designing a product that consumers become attached to, and that adds value is the definition of successful product design.

Product Development


When developing a new commercial product, there normally would be several design changes along the way, most successful products evolve to their final design through a process including the following steps:

  • Visual 3-dimensional cad prototype.
  • Alfa Prototype – Proof of concept.
  • Beta Prototype – Enhanced design and possible material changes from Alfa prototype.
  • Pre-Production Prototype.

Visual 3-dimensional cad prototype is when the product is designed to meet the initial product concept requirements in 3D, in a cad program, like Solidworks which can be measured, rotated and rendered, to help finalise the concept of design and materials, before a solid Alfa prototype is made.  Saving a great deal of time, money and energy, as most products can be designed up to 90% correctly before a solid Alpha prototype is made, and design changes are very easy.  The renderings and 3D design output can also be end user visually tested, to evaluate the product, and make sure that it is is on a successful design path. Tooling and part costs for production of parts with a range of materials and processes can also be recommended and estimated at this stage.



Alpha Prototypes are the first revision of a commercial product design and aim to meet all aspects of the product specification. They are developed for the purpose of facilitating a review of initial design requirements and implementation, and can produced directly from the Visual 3-dimensional cad prototype. We can use CNC machining process when real production materials and precision are required to validate the design. We have a wide range of production materials available from common grades such as PP, ABS and PC to engineering plastics like glass filled nylon, For complex prototypes we use can use a variety of additive prototyping techniques with very fast lead times – for example, SLA, SLS and 3D printing.

ABS machined ICA crest prototype

Beta Prototypes incorporate design changes that were identified during alpha prototype testing. Beta prototypes are often used for certification testing, trials and stress testing. These activities may prompt changes to the design specification and implementation of the product.

Pre-Production Prototypes are for verifying the design and manufacturing set-up prior to large scale production. This often includes optimising production yield, component suppliers, test processes and other considerations that can help streamline the manufacturing process.


Types of plastic molding processes.

Plastic molding is the process of shaping plastic using a mold. It started in  the late 1800s, making products like combs and buttons. There are many different  type of molding techniques to use for making plastic products. The methods range  from simple molding for common house products to complex molding designs and  flexibility for surgical or cosmetic products. Cost is also a factor in deciding  what type to use.

Blow molding

Blow molding is used to make items such as plastic bottles for beverages and  cosmetic product containers. The plastics are produced at high rates with this  molding method. The process combines extrusion and thermoforming techniques. The  machines heat plastic resin, made with a high or low density polyethylene, in  closed molds to make the desired shape of the mold cavity.

Injection molding

The most common form of molding plastic is injection molding. It produces  three-dimensional, solid parts with a moderate to high strength. Complex shapes  can be produced with this type of molding. The advanced molding techniques are  insert molding and reaction molding. Plastic is melted and injected into a mold  cavity. The plastic is cooled down. After cooling, the mold is ready to be  opened and the plastic form removed.

Dip molding

The process is the simplest means of molding plastic. It produces a large quantity of parts and product at a low cost. Some examples are surgical gloves, condoms and handles for tools. First, the metal molds are surface prepped to make the part easier to be stripped from the mold when it is dry. The part is  dipped into a polymer vat for a dip coating or a molding. Flexible products get a fabric layer applied between the polymer coats. Objects are then buffed and prepped so the plastic coating stays firmly in place.

Rotational molding

Rotational Molding is a product formed from a fine powder consisting of a  molten polymer inside a three dimensional mold. It rotates in a heated chamber.  When the mold is turning, the polymer sticks to the sides of the mold and  becomes a hollow part. The parts are uniform in shape and very high strength. Water tanks, Playground furniture and Kayaks are often molded this way, out of tough Polyethylene.

Structural foam molding

SFM process is used for parts that need thicker walls than the standard molding processes. A chemical or nitrogen agent is added to the plastic material. This allows the walls to become thicker. When the melted plastic enters the mold the foaming occurs.

Reaction injection molding (RIM)

The RIM moulding process is similar to injection molding except thermosetting polymers are used, which requires a curing reaction to occur within the mold. Common items made via RIM include automotive bumpers, air spoilers, and fenders. The most common RIM process material is polyurethane (known generally as PU-RIM), others include polyureas, polyisocyanurates, polyesters, polyphenols, polyepoxides, and nylon 6. If reinforcing agents are added to the mixture then the process is known as reinforced reaction injection molding (RRIM). Common reinforcing agents include glass fibers and mica. This process is usually used to produce rigid foam automotive panels. A subset of RIM is structural reaction injection molding (SRIM), which uses fiber meshes for the reinforcing agent. The fiber mesh is first arranged in the mold and then the polymer mixture is injection molded over it.

Metal injection molding (MIM)

Metal injection molding (MIM) is a metalworking process where finely-powdered metal is mixed with a measured amount of binder material to comprise a ‘feedstock’ capable of being handled by plastic processing equipment through a process known as injection mold forming. The molding process allows complex parts to be shaped in a single operation and in high volume. End products are commonly component items used in various industries and applications such as intricate metal parts for medical, dental, firearms, aerospace, mobile phones and automotive applications. The nature of MIM feedstock flow is defined by a physics called rheology. Current equipment capability requires processing to stay limited to products that can be molded using typical volumes of 100 grams or less per “shot” into the mold. Rheology does allow this “shot” to be distributed into multiple cavities, thus becoming cost-effective for small, intricate, high-volume metal products which would otherwise be quite expensive to produce traditional methods. The variety of metals capable of implementation within MIM feedstock are referred to as powder metallurgy, and these are: Iron, low-alloy steels, stainless steels, Aluminium alloys, bio-compatible alloys, carbides, ceramics, cobalt-based alloys, controlled-expansion alloys, copper and copper alloys, hard metals, heavy-metal alloys, magnetic alloys (soft and hard), nickel-based alloys, precious metals, reactive metals, shape-memory alloys, specialty alloys, titanium and titanium alloys, tool steels. Subsequent conditioning operations are performed on the molded shape, where the binder material is removed and the metal particles are coalesced into the desired state for the metal alloy.

The mold tool design.

Mold design is critical to the quality and economics of the molded part. Part appearance, strength, toughness, size, shape, and cost are all dependent on the quality of the mold. Key considerations for Engineering Thermoplastics are:

  • Proper design for strength to withstand the molding process pressures involved.
  • Correct material choice for construction, especially when reinforced resins are used.
  • Properly designed flow paths to convey the resin to the correct location in the part.
  • Proper venting of air ahead of the resin entering the mold.
  • Carefully designed heat transfer to control the cooling and solidification of the moldings.
  • Easy and uniform ejection of the molded parts.
  • Materials choice for mold, dependent on production volume. (Low volume, high volume)


When designing the part, consideration should be given to the effect of gate location and thickness variations upon flow, shrinkage, warpage, cooling and venting, of the part.  We will be glad to assist with processing information or mold design suggestions. The overall molding cycle can be as short as two seconds or as long as several minutes, dependant upon the process, with one part to several dozen ejected each time the mold opens. The cycle time for molding each part can vary by the heat transfer capabilities of the mold, the thickness of the part, part material choice and overall size of the part.

A few basic design rules for injection molded parts:

  1. Use uniform wall thicknesses throughout the part, this will minimize sinking, warping, residual stresses, and improve mold fill and cycle times.
  2. Use generous radius at all corners, the inside corner radius should be a minimum of one material thickness.
  3. Use the least thickness compliant with the process, material, or product design requirements. Using the least wall thickness for the process ensures rapid cooling, short cycle times, and minimum shot weight, resulting in the least possible part cost.
  4. Design parts to facilitate easy withdrawal from the mold by providing draft (taper) in the direction of mold opening or closing.
  5. Use ribs or gussets to improve part stiffness in bending, avoiding the use of thick sections to achieve the same stiffness, thereby saving on part weight, material cost, and cycle time costs.

General material types for thermo plastic molding:

  • ABS
  • Acetal
  • Nylon 6/6
  • PET
  • Polypropylene (PP)
  • Polyethylene (PE)
  • Styrene (crystal clear and opaque)
  • There are also many other types and grades of thermo plastics available for specific industry use, including bio-plastics, recycled plastics, glass fibre reinforced plastics and combinations of them.



We are a product design team that thinks differently.‹  We design, innovate, & produce high quality custom products that don’t cost the Earth.

  • Inventions, concepts, designs and ideas, transformed to a complete turnkey product solution ready for market.
  • Upgrades to existing parts or products that are labour intensive to manufacture, we can re-design them to a low cost hi-volume injection molded part.  Generally if you are hand making or machining above 100 parts, then the cost of re-designing and tooling up for injection molding, is very cost effective, and the cost per unit can be reduced by up to 80%.
  • New Products, custom designed and manufactured, in Australia or Offshore.
  • New molding dies, if you have an existing product that has production tooling, that is near the end of design life, or that is inefficient, we can design and manufacture a new replacement for you.
  • Confidentiality, we pride our-selves in keeping our customers’ intellectual property in-house, from design to production, so you have the peace of mind that what you tell us in confidence stays that way.
  • Confidence, with 30 years experience of product design and manufacturing, from Injection molded car parts, roto-molded sailing boats to nestable injection molded plastic boxes we won’t let you down.  We have many proven cost saving design solutions for products design just waiting to be implemented into your products. We can integrate fresh product styling with smart engineering, enhancing customer desire, while at the same time achieving tooling, part and assembly cost reductions. With 100+ different products being designed, and produced every year, by our team for our customers, we know how to achieve a winning product solution, that is both on time and cost effective.
  • Low cost, we specialise in the design and production of economical injection molding die solutions, for low and high volume production. If you want a part manufactured in volume, we can help you, reliably and at low cost.
  • Sourcing, we have a large data base of reliable product suppliers, which may already have a part or product that may match your requirements for a lower cost.
  • Start saving money today, email us in confidence with an existing design brief or concept, and we will quote you an estimated cost. Email us
  • Design guide, please feel free to review our free product design guide.

Share this: