Injection Molding Services

Molded prototypes and low-volume production parts in as fast as 1 day

High Quality Custom Injection Molding

Yiannopoulos delivers high-quality, on-demand injection molded parts. Injection molding is the cheapest process to make a plastic part at scale by offering consistent quality for mid-to-high volume manufacturing. Molding also has the highest variety of materials, colors, and configurations compared to CNC machining or even 3D printing. Beyond materials, injection molded parts can have custom cosmetics, polishes, or surface textures.

Yiannopoulos takes a “have it your way” approach to molding. We specialize in complex projects, typically requiring side action or hand loaded inserts. Our goal is to provide a long term solution, moving beyond rapid prototyping, with dedicated project managers and engineering experts to communicate through all project stages from design to production.

Yiannopoulos’ injection molding services include:

24-hour quoting with design for manufacturing (DFM) feedback
Large domestic partner network as well as international options
Single point of contact per customer
Expert consultation
Single, multi-cavity, and family mold options
Insert molding and overmolding
Most plastic materials, including custom sourcing and matching
Press availability from 30 to 1,100+ tons
Part inspection, including FAI and PPAP options
Customer-owned tooling

Is your project ready for injection molding? Upload your 3D model for a free quote.

Advantages of Injection Molding

Injection molding is an excellent option for the large-scale production of plastic parts and components. The advantages of using injection molding include:

Efficiency: The mold injection process is highly efficient, facilitating short lead times for large orders.
Superior detail: The high pressure of injection ensures that the melted material reaches every crevice of the mold before curing. This enables design engineers to incorporate complex geometrics and intricate elements into their designs.
Affordability: Fast and efficient production ensures a low cost per part, while high production volumes produce further economies of scale. Aluminum a cost-effective and readily available material can be used for tools to control costs.
High-volume production: Injection molding with steel molds can facilitate high-volume production of parts into the millions.
High tensile strength: Injection-molded parts may be reinforced by adding fillers into the liquid resin that improves tensile strength.
Ready-to-go finish: With the proper treatment, injection-molded parts come out of the mold with a smooth finish that requires no further refinement.

The Injection Molding Process

During the injection molding process, material is melted and mixed in a barrel where a reciprocating screw melts the material and feeds it into a split mold. The liquid material is then injected into a prototype mold cavity at high pressure to force it into all mold cavities before it cools and solidifies into the predetermined design shape.

This process is highly effective for the large scale production of industrial parts and components, and allows for the creation of products with multiple materials using repeated injection methods. Prototype injection molding wastes less material than other manufacturing processes and saves time by reducing the number of steps necessary to produce a given product.

Why engineers use Yiannopoulos for injection molding

Instant quoting & DfM feedback
Build and edit your quote online. Review your parts for manufacturability and assess the cost of different materials, processes and lead times for your project in real time.

Readily available capacity
Benefit from our network of 250 manufacturing partners to access instantly available capacity. Our manufacturing partners are both local and overseas.

Quality & reliability
Dedicated 3D Hubs team to ensure your parts consistently meet your quality expectations. We also offer phone, email and chat support for any concerns or questions you may have.

Our injection molding capabilities

Our network of Manufacturing Partners gives you easy access to diverse capabilities to serve all your manufacturing needs.

Name	Description
Minimum order quantity	100 runs
Mold material	Tool Steel P20, Carbon Steel S50C, Aluminum
Mold types	Rapid tooling, production tooling
Mold storage	Minimum 2 years
Mold lead time	2-3 weeks (Rapid tool), 4-5 weeks (Production tool)
Quality assurance	Inspection reports included, full dimensional report and material certifications available upon request.
Design verification program	Similar to First Article Inspection, you will receive 2 sets of parts upon the machining of the mold to test fit before continuing with full production.
Mold remachining	We can remachine the molds should any changes be required, changes to be reviewed on a case by case basis.
Reorders	Unit price is based on the quantity required for the reorder with an additional set up fee of $150/€100.
Additional technical support	Dedicated 3D Hubs Mechanical Engineer for technical support.

Our injection molding service

Our injection molding service allows you to seeminglessly move from prototyping to end-part production.

Name	Description
Rapid Tooling	Molds with aluminum inserts with a life time of up to 20,000 runs. Machined in typically 2-3 weeks.
Production tooling	Traditional hard molds, machined in typically 4-5 weeks.
Single cavity molds	Molds containing only one cavity, producing one unit per run.
Molds with side-action cores	Cores slide out of the part from the side before it is ejected from the mold. This allows for undercuts to be molded.
Multi-cavity molds	Multiple identical cavities are machined into the mold tool. This allows for more parts to be produced per shot, minimizing the unit costs.
Family Molds	Several parts are designed into the same mold tool. This allows for the minimization of tooling costs.
Insert molding	Inserts are placed into the mold and molding occurs around them. This allows for inserts such as helicoils to be molded in your design.
Overmolding	Premade parts are placed into the mold to mold over them. This allows for multi-material injection molding.

Available materials for plastic injection molding

All thermoplastics can be injection molded. Some thermosets and liquid silicones are also compatible with the injection molding process.

ABS
Common thermoplastic with high impact resistance, low-cost & low density. Vulnerable to solvents.

Nylon (PA 6)
Engineering thermoplastic with excellent mechanical properties and high chemical & abrasion resistance. Susceptible to moisture.

PC/ABS
Blend of two thermoplastics resulting in high impact strength, excellent thermal stability, and high stiffness. Vulnerable to solvents.

Polyurethane (PU)
Thermoplastic with high impact strength and good mechanical properties & hardness. Suitable for molding parts with thick walls.

Polypropylene (PP)
The most common Injection molding plastic. Excellent chemical resistance. Food-safe grades available. Not suitable for mechanical applications.

Polyethylene (PE)
Lightweight thermoplastic with good impact strength & weather resistance. Suitable for outdoor applications.

Polystyrene (PS)
The Injection molding plastic with the lowest cost. Food-safe grades available. Not suitable for mechanical applications.

Polyvinyl chloride (PVC)
Light weight plastic with good mechanical strength and abrasion resistance. Generally used in building and construction applications.

PEEK
High-performance engineering thermoplastic with excellent strength and thermal & chemical resistance. Used to replace metal parts.

Additives and fibers

Yiannopoulos offers additives and reinforcements as options for your plastics parts.

Name	Description
UV absorbers	Absorb UV radiation, slowing down the degradation of the material when used outdoors.
Flame retardants	Prevent ignition and inhibits spread of fire.
Plasticizers	Increase flexibility and promotes plasticity, reducing brittleness of the material.
Colorants	Used to color plastics.
Carbon fibers	Increase strength, toughness, and rigidity of the material at the expense of making the material more brittle.
Glass fibers	Increase strength, toughness, and rigidity of the material at the expense of making the material more brittle. It is more flexible than carbon fibers.

Available surface finishes for injection molding

Injection molded parts are not usually post-processed, but the mold itself can be finished to affect the surface finish of the molded part.

This way aesthetic needs or technical requirements can be achieved.

Name	SPI Standard	Description
Glossy	A-1, A-2, A-3	The mold is smoothed and then polished with a diamond buff, resulting in parts with a mirror-like finish.
Semi-gloss	B-1, B-2, B-3	The mold is smoothed with fine grit sandpaper, resulting in parts with a fine surface finish.
Matte	C-1, C-2, C-3	The mold is smoothed using fine stone powder, removing all machining marks.
Textured finish	D-1, D-2, D-3	The mold is first smoothed with fine stone powder and then sandblasted, resulting in a textured surface.
As-machined finish		The mold is finished to the machinist's discretion. Tool marks may be visible.

Injection molding design guidelines

The table below summarizes the recommended and technically feasible values for the most common features encountered in injection molding.

Feature	Recommended	Description
Wall thickness	Thickness: 1 mm and 3 mm	To avoid warping and sinking, parts should be designed with the smallest possible and constant wall thickness.
Smooth transitions	3 × wall thickness difference	If wall thickness cannot be avoided, use a chamfer or fillet to make the transition as smooth as possible.
Rounded edges	Internal edges: > 0.5 × wall thickness External edges: internal fillet + wall thickness	Add a fillet with a radius that is as large as possible to all internal and external edges.
Draft angle	For parts taller than 50 mm: increase the draft by 1° for every 25 mm	For parts with a textured finish: increase the draft by an extra 1°-2° Add a draft to all vertical walls to make the ejection of the part easier and avoid drag marks.