6 Rapid Tooling Manufacturing Technologies

 

What is rapid tooling? Detailed analysis of 6 rapid tooling manufacturing technologies

In modern manufacturing, the manufacture of rapid tooling is mainly used in the prototype design stage of products. It has the advantages of short manufacturing cycle and low cost.

This article will take you to understand the six manufacturing technologies of rapid tooling, each of which has its advantages and disadvantages. Whether you are an industry expert or a reader interested in mold manufacturing, this article will provide you with direction for choosing rapid tooling manufacturing technology.

What is rapid tooling?

Rapid tooling (RT for short), also known as rapid prototyping mold, is a process method that uses rapid prototyping

 (RP) technology or combines traditional processing methods to quickly manufacture functional molds. The core concept of rapid prototyping is to shorten the mold development cycle and reduce the mold manufacturing cost, especially for small batch trial production, product verification and rapid production stages.

Rapid molds can be divided into the following according to the number of uses and life requirements:

Soft molds: short life, cheap, usually made of plastic materials such as silicone and epoxy resin;

Hard molds: relatively long life, but relatively high price, usually made of durable metal materials such as steel, suitable for small batch production.

Rapid tooling are different from the mass-production and long-life design concepts of traditional molds. They focus more on development speed and economy, and do not pursue service life too much. However, service life is a key factor for casting molds that require mass production.

Detailed introduction to the six manufacturing technologies of rapid tooling

If you are interested in how rapid tooling are made, this article can fully answer your question. Below I will introduce six manufacturing technologies in detail, namely: 3D printing technology, CNC machining technology, silicone rubber mold manufacturing technology, arc spraying molding technology, injection molding technology, and precision casting technology.

(1) 3D printing technology

● Principle:

3D printing is a layer-by-layer additive manufacturing technology that converts digital models into physical parts by melting or solidifying materials. In rapid mold manufacturing, the mold can be printed directly, or the master mold can be printed for re-molding.3D printing is the most effective process for prototyping.

● Common processes:

SLA (photocuring resin printing)

SLS (selective laser sintering)

SLM/DMLS (metal laser melting/sintering)

● Advantages:

Supports highly complex designs, such as molds with complex internal cooling channels

Short development cycle, no molds or tools required, and is the fastest of the six manufacturing processes

If changes are required, it also supports modification

The processing material can be plastic or metal, of course, plastic molds are faster to manufacture

Supports customization to meet the personalized needs of customers

● Disadvantages:

For high-strength and heat-resistant materials, 3D printing has certain limitations

For metal material printing, the cost is relatively high

The accuracy and strength of 3D printed molds are limited, not as high as CNC processing, and usually require post-processing

The mold life is usually low, especially for plastic molds

(2) CNC processing technology

● Principle:

Use CNC machine tools (such as milling machines and lathes) to precisely cut metal or plastic materials into mold cavities or cores. For fast molds with high precision requirements, milling their internal cooling channels is an effective solution

● Advantages:

High processing accuracy, the highest among the six manufacturing methods

High mold strength, suitable for injection molding or die-casting molds

Supports a variety of metals (such as aluminum, steel, copper) and plastics

CNC processing technology has a high degree of automation and is suitable for small batch production

● Disadvantages:

Using CNC technology to manufacture rapid tooling is costly and difficult to process, and usually requires multi-axis machine tools

Relatively difficult to modify, and the processed area cannot be modified again, which is far less convenient than 3D printing

The manufacturing time and speed are relatively long, and this process is not suitable for customers with very short time requirements

(3) Silicone rubber mold manufacturing technology

● Principle:

The master mold (usually 3D printed or CNC processed) is embedded in liquid silicone rubber, and the master mold is removed after curing to form a soft mold for vacuum injection molding

● Advantages:

Lowest cost, fast manufacturing (1-2 days)

The precision of the master mold is as high as that of the copied mold

The mold is soft and has good demolding properties

Suitable for small batch plastic parts production

● Disadvantages:

The mold life is short and cannot be used after about 10-50 times.

Not resistant to high temperature and corrosion

Poor dimensional stability, easy to aging and deformation

(4) Arc spraying molding technology

● Principle:

Use arc discharge to melt metal wire, and then use compressed gas to spray metal powder onto the surface of the substrate at high speed to form a metal coating, which is then accumulated layer by layer to form the shell of the mold.

● Advantages:

Suitable for large molds

Fast manufacturing speed

Lower cost than integral metal molds

Can be directly sprayed on the surface of the master mold

● Disadvantages:

Limited molding accuracy, requiring subsequent processing

Limited coating bonding strength, easy to fall off

Suitable for low-pressure injection molding or low-load scenarios

(5) Injection molding technology

Note: "Injection molding" here is used for rapid mold verification, not mass production mold manufacturing.

●  Principle:

Thermoplastic plastic is melted and injected into the mold cavity, and the product is obtained by cooling and solidification. Rapid tooling produced by injection molding are only used to verify whether the mold structure is reasonable, such as whether the cavity design and runner design are reasonable, and are not used in actual industrial production.

● Advantages:

The mold quality can be verified under actual processing conditions

High consistency with the final mass-produced parts

High efficiency

● Disadvantages:

Injection molds must be made first

Compared with soft molds, the mold manufacturing cost is high

The process equipment is complex

(6) Precision casting technology

● Principle:

Use 3D printing or wax molds to make casting models, and obtain metal molds or mold cores through investment casting. It is also used to make mold cores or inserts.

● Advantages:

Complex cavities and thin-walled structures can be formed

A wide variety of materials (steel, aluminum, copper, etc.)

The cost is lower than CNC machining, suitable for small-batch metal production

The mold manufacturing of functional integrated parts can be realized

● Disadvantages:

Accuracy depends on model quality

Shrinkage control is difficult

The cycle is slightly longer (much slower than 3D printing)

Summary

Rapid tooling provide many benefits to manufacturers, such as saving time and reducing costs.

The above introduces six commonly used rapid mold manufacturing methods, and gives a detailed introduction to the principles, advantages and disadvantages of each technology. At the same time, you can also choose the technology that best suits your needs by comparing the manufacturing cycle, manufacturing accuracy, manufacturing cost, etc. between these technologies.