We have many different conversations with clients and prospective businesses every day where questions are asked. Due to the complexity of what we do, we have in this section of our website, some of the more frequently asked questions for you to look through. If your question isn't here, then please feel free to call us on 01626 830113 and ask a member of our team!
Q: How do I design a product for manufacture?
A: You don’t! This is a very specialist area where a product design agency will be able to guide you through every step you need to make sure your product can actually be made – and made to the right specification. You can find out more about our product design services here.
Q: Why is the mould tooling so expensive?
A: Full hardened steel is not a low cost commodity, and the work involved in cutting steel for the complex design of an injection mould tool takes expensive equipment, skilled personnel and a lot of time.
Q: Why does it take so long to get a Fully Hardened Tool made?
A: It takes time to get things right! You should usually see first off samples within the first 6/8 weeks – this is the time it takes to design the tool and design the cavities so that the tool can produce a sample of your item. This first sample, or T1, will not have any texture but it will be a good representation of the item so that it can be tested for fit and function. T2’s will have any modifications that are needed, and T3’s will normally be a good representation of the finished item, to include surface finish and all features ready for you to sign off.
Q: Can I reduce the time it takes to manufacture a tool?
A: Yes, there are other methods of tooling for low volume manufacture, but you will always get what you pay for – so the tool life may be 10’s or 100’s of products rather than the hundreds of thousands offered by a fully hardened Injection Mould Tool.
Q: Aren’t plastics bad for the environment?
A: Items that are disposed of, rather than recycled, are one of the biggest issues this planet faces. Plastic carrier bags for example cause a huge amount of Ocean pollution, whereas, most injection moulded items have been designed to be used, repaired or recycled. This recycled plastic can then be re-granulated and used again to make something else. You can read more about Amtek's recycling policy here.
Q: Explain the term ‘thermoset polymer’, with reference to molecular structure.
A: Once 'set' these plastics cannot be reheated to soften, shape and mould. The molecules of these plastics are cross linked in three dimensions, this is why they cannot be reshaped or recycled. The bond between the molecules is very strong.
Q: Explain the term ‘thermoplastic’, with reference to molecular structure.
A: These plastics can be re-heated and therefore shaped in various ways due to their long chain monomers that are not inter- connected. They become mouldable after reheating as they do not undergo significant chemical change. Reheating and shaping can be repeated. The bond between the molecules is weak and becomes weaker when reheated, allowing reshaping. These types of plastics can be recycled.
Q: What Are The Advantages Of Plastics Over Metals?
Easy to handle
Q: What Is Mfi?
Mfi stands for the flow capacity of different grades of thermoplastics which are inversely proportional to molecular weight.
Q: What are Fillers And Additives?
Fillers and additives are small molecules which are added to plastics to get some characteristics (colour, flexibility etc.). Fillers are commonly used with thermosetting plastics. Additives are available as two types:
Physical additivies - plasticizer
Chemical additivies - stabilizer
Q: What Are The Mould Release Agents?
External release agents are applied to the mould surface e.g. Polyvinyl alcohol
Internal with resins eg. Silicon oil
Q: What Is Injection Capacity Or Short Capacity?
Maximum volume of material injected by the screw during one cycle of operation.
Q: What Is Plasticizing Capacity?
It is the amount of material that can be processed by the machine per hour. It is expressed in kg/h.
Q: What Is Injection Pressure?
It is the maximum pressure by which the material is injected through the nozzle. It is given in kg/cm2.
Q: What Do You Mean By Clamping Force?
It is the maximum force that the clamping system can exert on the mould or it is the maximum force by which the mould halves can be closed together. It is given in tons or kilo Newtons.
Q: What Are The Types Of Injection Mould?
Two plate mould
Three plate mould
Hot runner mould
Insulated runner mould
Hot manifold mould
Q: What Is a Two Plate Mould?
A two plate mould is a mould which consists of a core and cavity situated in plates. It is a logical type tool where the component requires a large gate. For simple type components there is only one daylight.
Q: What Is a 3 Plate Mould?
A 3 plate mould consists of feed plates with a core and cavity.
Q: What Is a Hot Runner Mould?
In a hot runner mould the runner must be kept hot to keep the molten metal in a fluid state, also called a runner less mould. In this, the runner is contained in a plate in its own runner section of the mould which is not opened during the molding cycle.
Q: What are the Advantages Of a Hot Runner?
No moulded side products
No separating of gate
Cycle time can be reduced
Q: What Is an Insulated Runner Mould ?
It is a variation of a hot runner mould where the outer surface of the material in the runner acts as a insulator.
Q: What Is a Hot Manifold Mould?
This is a variation of the heated hot runner and not the runner plate. This is done using an electric cartridge.
Q: What Do You Mean By a Stacked Mould?
A stacked mould is a multiple two plate mould with the moulds placed one over the other. A stacked mould construction doubles the output from a single moulding machine and requires the same clamping force.
Q: What is Injection Moulding?
In this process, the plastic material is injected in to the mould through a sprue bush by means of a screw plunger. This process can be used for both thermosetting and thermoplastic materials.
Q: What Is Compression Moulding?
In this process, the plastic material is placed in the cavity and uses a force for compressing the compound as the mould closes. These moulds are generally used for thermosetting materials.
Q: What Is a Transfer Mould?
In this process, the plastic materials are transferred from a transfer pot and then forced in to the cavity by means of a plunger. This method is used for moulding thermosetting materials only.
Q: What is Blow Moulding?
Blow molding is very much like compression moulding because the blow mould generally closes on a hollow shape that has been deposited in between the halves of the mould. Air or gas pressure is introduced at the center. This internal pressure causes a flow of the heated material to make intimate contact with the relatively cold mould sections. Here the plastic material solidifies and is subsequently ejected.
Q: What is Vacuum Moulding?
The mould used for vacuum moulding is similar to that of the female half of the compression or blow mould auxiliary equipment on the machine. The machine heats up the material and drags it over the cavity as indicated by the precise technique chosen.
Q: What is Rotational Moulding?
The machine holds the mould and rotates it about two axis at the same time. This rotation causes the powdered material, that was loaded in to the mould before it was clamped into the machine, to solidify and cling to the wall of the mould.