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How molding process creates Custom-made Plastic Parts?

2021-01-17 hqt

What is plastic mold design?


Plastic design is the important analysis in the manufacturing and accomplishing of the design of the specific part. The plastic design has the specific criteria in which the analysis of het design of the product is the ultimate load. In this process, we study an inelastic material and its properties and characteristics for the purpose of Custom-made Plastic Parts.

The importance of the plastic design is significantly important in the case of mode failure. Therefore, the ultimate load in the process is the characteristic of the strength of the steel in the range of plastic. Hence, this method of the analysis of the plastic design is fast and accurate. Moreover, this method has the quick and rational approach in the design of plastic parts.

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What is the best material for making a mold?


Most of the materials that have the excessive use in the mold making consist of rubber. This rubber in the materials for the mold making is of two types. This is the natural and artificial rubber. The most common and significant type of the plastic is neoprene. It has the widespread use in the formation different types of molds.

However, there are many other materials for the purpose of the formation of molds. The significant of them are gypsum plasters, natural latex, polyurethane, epoxy and silicone. Thus, the best option of the material for the purpose of molding process is silicon rubbers. The silicon rubbers are the main and important category of polyurethane and polyester resins.

The molds that we make from these materials have the capacity to fabricate up to hundreds of the parts. However, if we need the smaller number of parts from these molds, then we use the low-quality molds of these materials. For this purpose, we need the low-quality polyurethane mold rubber.

How do you design plastic parts?


The designing of the plastic parts is not similar to the designing of metal parts. This plastic parts design is considerably different and has many techniques to consider in the process. There are many ways in which we can design the plastic parts. These include injection molding, thermoforming, extrusion, blow molding, even casting.

Injection molding is an important method to design the Custom-made Plastic Parts in an effective way. In this method, we take the plastic in the molten or heated state. Then we inject this molten plastic into the mold for the plastic part design. When the molten plastic cools down, then we can eject it out from the plastic mold.

The plastic molds are usually in the two basic forms. One of these types can state the outer properties of the plastic part. This type of the plastic made is called the cavity. The other type of the plastic mold is that which describes the internal features of the plastic part. This type of the plastic mold has the name of core. Both are essential in the formation of Custom-made Plastic Parts. 

What are the plastic defects?

In any manufacturing process, there is a tendency of occurring the defects and errors. These defects and errors can occur due to the mismanagement of the materials, equipment and the personal efficiency. We can remove and mitigate these defects with the help of troubleshooting these errors and defects. The most common types of the errors that we encounter are as follows.


Blister is the raised and uplifted part of the plastic design on the surface of the plastic part. It has the same meaning as there is in the medical field for the raised area. This type of the defect in the Custom-made Plastic Parts arises due to the uneven heat. If the molding machine faces the high heat and temperature during the process, it can lead to the problem in injection.

Due to the issue in the injection of the molten plastic, the blisters arise on the surface of the plastic parts. However, it also occurs due to the interference of the air with the molten plastic during the process. This can cause the formation of the blister in the process of cooling and venting. If the molding machine faces the problems in the flow of the molten plastic, then blisters are common.

Burn marks

The formation of the burn marks is the problem similar to the blistering of the plastic parts. This defect in the plastic parts manifest in the form of the black discolorations on the surface of the plastic part. The common reason for the development of the burn masks is the inadequate ventilation of the resin or the material.

When the burn marks occur due to the improper ventilation of the resin, the burn marks arise on the location that is away from the ventilation gate. The burn marks can also occur due to the trapping of the resin in the injector. When it happens, the resin heats up for a long time period. In this case, we can solve the problem b cleaning the device and injector.


In the most cases, the problem of formation of the burrs occurs in the process of formation of Custom-made Plastic Parts. These burrs appear on the surface of the injected material. This problem usually occurs when we attach a number of the pieces to the plastic part. The common type of the burrs in the daily life are present in the green plastic Army men.

The green plastic army men have usually extra pieces of the parts on their heads. Moreover, they can also have the sheets of plastic that connects their arms with their bodies. The most trending cause of the burrs is the presence of the inaccurate and inadequate cut dyes. If we refurnish and repair the cut dyes, this defect reduces and mitigates to the maximum extent.

Custom-made Plastic Parts 2021

Flow marks

The flow marks are also important and common during the formation of Custom-made Plastic Parts. These flow marks appear as the discolored lines or the patterns on the surface of the plastic parts. These flow marks destroy the shining and smooth surface of the plastic part.

The common cause and root of the formation of the flow marks is disturbance in the temperature of the injector. When the injector is performing its function at a low temperature than the requirement, this type of the defect is important. This problem can also arise due to the malfunctioning of the ventilation gate during the process.

Is 3d printing cheaper than molding?


The 3D printing is not cheaper than the plastic molding when we prepare the plastic parts at commercial level. However, in some cases, 3D printing can help us a lot as compared to the injection molding process. The reason behind it is that we use the large 3D printing formats in this technology.

You can use 3D printing effectively if you need the Custom-made Plastic Parts in the low amount. 3D printing is usually preferable in the process if the target of the product is less than 10000. The reason is that 3D printing focuses on the cost efficiency of the product per piece. When the product is required in a large volume, the injection molding is more economic.