Stack molding for plastic injection molding

Stack molds are some of the remarkable production tools to be found anywhere. The craftsmanship and engineering that goes into a stock mold is really  marvel.

For the layman, who has never built a plastic injection mold, it might look like a fancy, huge piece machinery that generates plastic widgets. Yet, from the perspective of an plastic mold maker, stack molds represent an extremely high level of expertise.

What is a stack mold?

There are different variations on the theme of stack molds, but some general specs are:

  • Built for extremely high production runs
  • Have a one cavity and different cores
  • Use indexable cores to injection and mold multi-materials
  • Have the capability to do different operations in the molding cycle

Basically, a stack mold has a stationary “A” half, and at least 2 “B” or moveable halves. They are alike to the rotary molds that have been in use for many years, but are vertical rather than horizontal.

This means that the portable cores rotate about a vertical axis, rather than a horizontal. Also, the stack mold is extremely compact and has a much little footprint.

Plastic molding parts
Plastic molding parts

What are the applications of stack molds?

Because they are top production products, the general applications are for consumables and cosmetics, such as toothpaste or deodorant containers. Medical and automotive products are normally produced using stack molds.

More and more items are being designed to use soft overmolding, such as hairbrushes or toothbrushes. These are best applications for stack molding. Because the part is plastic molding parts, chilled, overmolded and ejected in sequential cycles, production costs can be reduced.

What are the advantages of stack molding?

Stack molds are accessible in different configurations to meet a big range of molding demands and Cosmetics injection molding. Stack molding provides an economical and perfect manufacturing solution for the production of multiple plastic molding parts. Injection molding china firms are forever looking for more perfect way of molding and for the right.

A few of the advantages of the stack molding process contain: increased output efficiency

  • Reduces number of machines needed
  • Lower machine size need Vs. multi-cavity single face molds
  • Generate twice as many parts without rising press size or clamp tonnage, which greatly decreases part costs
  • Set-up time and run-time cost are divided by all the parts generated
  • Producing the back and front parts of a key fob at the same time is a best example of an application of stack molding
  • Mold ejection functions are self-contained, no extra labor or steps needed.

Looking for injection molding China partner to support your stack mold project? Contact us to get price.

Vacuum Resin Transfer Moulding

Our new Vacuum Resin Transfer Moulding facility has now been added to the MTM manufacturing process. Key advantages to VRTM are;

Low cost tooling, whilst maintaining high quality parts.
Perfectly Tailored for lower volume projects.
Inserts & fasteners can be incorporated within the moulding.
Encapsulation of structural cores.
High quality finish out of the mould, without the need for additional operations, such as painting, polishing etc.
Good definition on the moulded ‘B’ surface, this can be equivalent to the ‘A’ surface, if part is visual.
Highly Structural composite structures, moulded to tight dimensional tolerances (+/-0.5mm on thickness and flatness)
Complete structural deck sections with complex foam cores and integral fixing points.

Plastic Injection Molding Service

During 2013 MTM invested in an expansion programme at our West Midlands Site, encompassing  a brand new injection facility with machines ranging from 100T  to 600T.  Combined with our existing assembly and paint facilities, MTM has the ability to fulfil a diverse range of customer requirements for small, medium or large volume projects.  

Materials Available:
Nylons PA6, PA6.6
Metal replacement Nylons,  
PBT, Acrylic,
Glass filled Nylons
Polypropylene Talc filled and Mineral filled
High Impact Polystyrene

Should you require any assistance with material selection for your specific project, please do not hesitate to contact our technical team who will be happy to assist.

Have any projects that need plastic injection molding service? Go to

‘Krismalex’ Electrical Standoff Insulators have excellent electrical properties and outstanding dimensional stability.

Each Standoff Electrical Insulator is manufactured from glass reinforced moulding compound, which make them preferable to traditional types of insulators, particularly when components are likely to be subject to heavy duty or to exceptionally high mechanical forces.

The general electrical properties of glass reinforced polyester materials have led to their extensive use for Electrical Standoff Insulators . Resistance to tracking and insulation resistance is both excellent and components can safely be specified in suitable grades of material for use in high current arcing conditions.

Standoff Insulator Insert Material
Brass as standard. Zinc plated mild steel also available.

Krismalex Electrical Standoff Insulator Types
• Standard Low-Voltage Type 1333 Insulator
• Pillar Type 1506 Insulator
• Flanged Type 1635 Insulator
• 3.3kV Waisted Type 1365 Insulator
• 6.6kv Stand-off Type 1546 Insulator
• 7.2kV Post Type 1732A Insulator
• 11kV Post Type 1732B Insulator

Standoff Insulator Material
Glass reinforced polyester moulding compound – general-purpose grade G, reduced flammability grade G/B, arc resistant grade G7/B, or UL94 V0 grades.

Composite Moulding

An eggshell is perhaps the best-known natural composite.

Composite materials are basically highly engineered combinations of polymer resins and reinforcing materials such as glass fibers that are incredibly strong, durable, flexible and non-corrosive.

The term “composites” is used broadly to describe a large range of materials that have generic reinforcement. These are combined with various resins that can be used for a large number of applications and are thus ideal for highly engineered materials targeted at specific applications. They are rapidly replacing products made the more traditional way from alloys and other metals. As raw materials become more expensive, so composites become a much more attractive and cost-effective proposition.

The expertise of MTM Plastics is in composite moulding. Examples of this type of technology can be found in many different industries today. Aviation is one such area that has embraced composites technology, with over 57% of aircraft components being made by this process. The Mass Transit industry, globally, also has taken the composites philosophy on board. If you travel today anywhere in Europe by train, the seats you sit on may well have been manufactured by MTM Plastics.

Durability, weight and corrosion are the three main advantages of choosing composites. Compared to steel and aluminium and based on density, composites have a superior stiffness-to-weight ratio. Given the same strength they are lighter than steel by 80% and aluminium by 60%. Many composites withstand continuous high operating temperatures up to 250˚C (482°F), and are highly resistant to corrosion.

The non-reactive nature of many resins and reinforcements can be custom-selected thereby resisting decomposition and degradation in chemically corrosive environments.

Durability is also a plus – well-designed composites have exhibited apparent infinite life characteristics, even in extreme environments.

Economically they make more sense. Composites offer designers an increasing array of choices through the vast range of materials on offer. The trend to use composites is highly favourable, especially when comparing the cost of fabrication. Our process allows the formation of a component in a single pressing, guaranteeing repeatability and consistency. This combined with lower initial start up costs and durability makes composites the right choice for many applications.

Improved safety.
On worksites, the electrical insulating properties of composites are inherent (depending on reinforcement selected). Alternatively, composites can be made to conductor selectively conduct electricity. Tunable energy management characteristics, with high-energy absorption or high-energy conductivity, are also possible. Made to Measure thermal expansion properties can be compounded to closely match surrounding structures to minimize thermal stresses. Composites have such exceptional shaping and forming properties they are more comparable to the proverbial ‘putty’. They can be made to almost any shape during fabrication. The composites’ inherent shaping and forming characteristics allow production to be established for a fraction of the cost that would be required in a metallic fabrication. Even in extremely harsh environments, well-designed composites have shown such infinite life characteristics they may well last an eternity.

Looking for more service about plastic injection molding and composite moulding service, please go to


  • Exhibition & Convention Area: 102,000 sq. mts.
  • Spread over 45 acres
  • 15 Exhibition Halls
  • High load bearing floor capacity of 10 Tons / sq. mts –
  • Ideal for live demonstration of heavy machinery
  • Exhibition hall’s towering ceiling height – 7 to 18 meters.
  • Can be converted into double storey booths
  • 10,000 car parking and over 500 trees
  • Inbuilt Media Lounge, Protocol Lounge & Control Room


INDIA PLAST 2015 is a global congregation of plastic industry. An Exhibition conceived and promoted by the Government of Gujarat, it will provide a dynamic interactive platform for everyone who matters in the plastic industry across the globe…manufacturers, suppliers, innovators, technologists, consultants, investors, customers.

The Exhibition will showcase the latest technological developments in the field. It will also offer a world of exciting global technological know-how, consulting and joint venture opportunities. The focus will be on exploration, innovation, expansion and co-operation.


INDIA PLAST 2015 will focus on promoting a progressive image of Indian plastic industry on a global platform. It will act as a catalyst and facilitator for buyers and sellers, bringing together the entire global plastic fraternity. It will help the Indian industry imbibe the latest plastic molding technologies even while showcasing their achievements to the world. It will provide an ideal opportunity to network with industry peers and thought-leaders and expand industry in every sphere.


Raw Space : 27-01-2015 (Time : 10 am to 6 pm)

Shell type : 28-01-2015 (Time : 10 am to 6 pm)

After official closing of exhibition (03-02-2015, 5 pm to 04-02-2015 before 11:00 am)

Move Out Time : 03-02-2015 (Time : 07 pm)

  • Deadline to complete exhibit transfer and stall decoration before 9 pm on 28-01-2015
  • Transfer of material/goods will not be allowed during exhibition


  • Exhibitor’s product profile for participant directory : 30-11-2014
  • For final payment : 30-11-2014
  • To submit additional service requirement form :30-11-2014
  • Specification of loading/unloading : 30-11-2014


Upto 30th April 2014After 30th April 2014
Shell Package
(per sq mtr)
Raw Space 
(per sq mtr)
Small scale (SME)Rs 4500/-Rs 4000/-ForeignUSD 125USD 120Corporate / Govt.Rs 11000/-Rs 10000/-
Shell Package
(per sq mtr)
Raw Space
(per sq mtr)
Rs 5400/-Rs 4800/-USD 140USD 135Rs 13200/-Rs 12000/-

(12.36% Service Tax will be applicable on above charges)

  • 2 side open 15% extra
  • 3 side open 25% extra
  • 4 side open 30% extra


Carpet Floored Constructed stall with Exhibitor’s Name on Facia, One Laminated Table, One Dust bin, Three Spot lights, One 5 Amp. Plug Socket for every stall of size 9 + 500 nos. of Invitation Cards, One Exhibiton Souvenir, Three Exhibitor Badges, One entry in participant directory.


this comprises of bare space only. (Exhibitors will have to construct their own designed stall.)


INDIA PLAST 2015 is going to be held at Mahatma Mandir Exhibition & Convention Centre, which is designed with state of the art technology and infrastructure.

  • Inbuilt media lounge
  • Protocol lounge & Control room
  • Large parking area for over 10000 cars with elegant exterior design
  • High load bearing floor capacity for heavy machinery