3 Common Types Of Rapid Prototype Injection Molding Methods

Rapid tooling is the process of creating a mold in a shorter timeline. It started as an experiment to see if it could work seamlessly in a factory environment. A rapid-tooled mold is a great tool for creating small-scale plastic parts before a full-scale production run begins. This process involves only inserting a part, which is usually the insert cavity. Depending on the type of rapid tooling used, you may be able to get thousands (or tens to hundreds of thousands) of cycles out of the tool.

There are various types of rapid tooling available, each of which has its own advantages and disadvantages. Before you decide on one, make sure that you understand the limitations of each type of rapid tool.

The mold material must be strong enough to handle the rigors of injection molding. Also, it must be able to withstand the effects of hot plastic injection.

The mold needs to be smooth enough to eject a plastic part. This is especially important during rapid tooling processes.  This means the rapid tooling mold could require additional work after it is created to make it smooth enough for prototyping.

The mold may not have enough tolerances. If the tolerances are not tight enough, the plastic may not be able to produce desirable results.

With that in mind, here are three of the most common rapid tooling methods available in prototyping:

1. Plastic 3D Printing

3D printing has become increasingly popular in plastic injection molding. Aside from being incredibly fast, the machines can also produce virtually any shape or size you need. In most cases, the cost of production is also significantly lower than traditional metal printing. The advantages of 3D printing over metal are many, including its ability to produce virtually any geometry needed. However, unlike metal, 3D printing doesn't allow for exceptional part tolerances.

2. Direct Metal Laser Sintering

Metal can also be used to make a plastic injection molding using a process known as sintering. This involves combining metal particles with a liquid solvent to make a plastic mold. Sintering is a process that involves spraying a cloud of powder metal into a laser beam, letting the user draw the mold's shape using the device. This process can be done with a variety of metals, such as titanium, chromium, and steel. This process can be done in various metals, such as titanium, chromium, and steel. Due to their properties, these materials are more durable and can handle various conditions.

Sintering is a process that allows you to print cooling lines on a part, which helps keep it cool enough to avoid it getting deformed. This process is commonly used to make a mold for a special type of deodorant cap. Due to the shape of the lid and the thin wall around it, it needs to be cooled as quickly as possible to avoid deforming. This process is done using a cooling line that's buried within the steel.

Keep in mind that while sintering is fast, it’s not accurate enough to achieve the required +/-.001 tolerance right out of the machine. Instead, it will achieve a tolerance of +/- .004 or +/-.005, but to get the tighter tolerance, due to the complexity of the material used, traditional machining techniques are often used to achieve the same accuracy. However, the use of EDS can lead to expensive sintering.

3. Traditional Machining Rapid Tooling

While rapid tooling allowed companies to build molds using traditional methods, those methods started to catch up with the faster production methods. Rapid tooling became the term for any tool that could be built quickly. Some companies can produce a metal mold in a few days to a week. This method works well for creating prototypes, but it can also be limited when it comes to working with geometry. If you need a complex geometry in your mold, rapid tooling could be more expensive than traditional machining, but in China, the cost can be much lower as the lower labor cost and manufacturing abilities.

Are one of these types of rapid tooling right for your products?

Although rapid tooling can create a mold in a shorter amount of time, it often requires more finishing touches to make sure that the mold is completed properly.If you have a question about creating a mold for your part, please contact TEAM MFG today!