Custom Aluminum Injection Molds

Low volume injection molding
Bridge tooling
Pilot runs
Functional testing and prototyping

Aluminum Injection Mold Making Service

The aluminum injection mold is a low-cost tool that shortens the manufacturing time, so it is very flexible in mold manufacturing and plastic injection molding production. Since it is a method of simplifying mold structure, the aluminum mold is often referred to as rapid mold or test mold. Aluminum injection mold is often used in low volume injection molding production, often in the field of rapid injection molding.

As you know, CNC manufacturing prototypes are the most important method used to verify products in the product development process, and steel molds are the most economical way to mass production of plastic products. Because of its lower cost and shorter production cycle than steel molds, and the mass injection output can reach 100-10,000 pieces, aluminum injection molds have become an important means of product development and rapid manufacturing.

As one of the reliable aluminum injection mold makers, We will provide you with a complete one-stop service from design to the final product. if you have any projects, you are welcome to contact Sungplastic for a free quote.

Use Aluminum Molds for Low Volume Manufacturing. WHY？

Traditional injection molding can usually produce millions of plastic parts. However, manufacturing the required steel molds usually takes several months and is much more expensive. But what if the production demand requires a small batch? This is the ideal place for aluminum injection molds.

If your demand for the number of parts will not reach millions, or if you need to produce parts on-demand within a few days, and if you want to avoid high-risk mold investments before the part design is truly verified, then use aluminum molds for small batch Injection molding may be a good choice. Once the aluminum injection mold is ready, injection molding production begins almost immediately. This allows each order to be manufactured in three weeks or less.

1. Simplified mold design reduces mold structure, saving manufacturing time and cost.
2. Improve heat dissipation, no need to use messy cooling lines.
3. Mold production and parts manufacturing are completed in 15 days or less.
4. The mold manufacturing cost is low, ranging from a few hundred to 2,000 US dollars.
5. Single cavity and multi-cavity molds: According to the size and complexity of the parts, 1-cavity, 2-cavity, 4-cavity and 8-cavity molds can be used.
6. Thermoplastic and thermosetting materials are the same as materials for mass production. More than 100 different materials can be used, including ABS, PC, PP, PE, POM and silicone rubber.
7. The production quantity does not exceed 10,000 parts. For more quantity requirements, steel molds can be considered.

Process of Making Aluminum Injection Mold

Aluminum injection molds are easy to machine and have high dimensional stability, mainly through rapid CNC machining, wire cutting, and EDM processing to form single-cavity or multi-cavity molds. The excellent thermal conductivity of aluminum improves heat dissipation, eliminating the need for messy cooling lines and saving mold cooling time by up to 50% during production.

The thermoplastic and thermoset materials used in plastic molding production are the same as the mass-produced materials. More than 100 different materials can be used, including ABS, PC, PP, PE, POM and silicone rubber.

In the past few decades, the pressure to shorten the cycle time of manufacturing molds and molded parts has raised the level of the mold industry to a new level. Under the right conditions, aluminum injection molds have also become an excellent choice for long-term production.

Compare Aluminum Injection Mold vs Steel Mold

Aluminum injection molds are very suitable for small batch production. Compared with traditional metal molds, they provide a cost-effective solution with a shorter lead time. For aluminum molds, we are usually 30-50% cheaper than producing injection molds. Compared with steel injection molds, the lead time is shortened by 40-60%.

Advantages of aluminum injection molds:

The processing time of aluminum molds is much shorter than that of plastic injection molds. For example, the cutting speed is faster than steel, and the cooling speed is 5 times faster than P20 steel.
The processing cost of aluminum molds is much lower than traditional molds. A shorter processing time leads to more savings in processing costs.

Challenges of aluminum molds:

The mold life is shorter than the steel mold life.
The total number of products that can be produced is much smaller.
The tolerance is wider than traditional tools.

Mold selection:

On-demand manufacturing, select the appropriate mold type.

Rapid aluminum injection mold, suitable for products with less than 10,000 times.
The P20 prototype mold is suitable for products that are more than 50,000 times.
NAK80 or S136 molds are suitable for products up to 100,000 times or more.

Aluminum injection molds Can Make Complex Parts?

Due to its soft nature, aluminum injection molds are unsuitable for complex parts and can only be used for simple injection molded designs. If a design has intricate geometry, a steel mold is necessary as it can handle thin walls and complex shapes better than aluminum. The structural strength of steel is superior to aluminum, which can deform during the molding process, rendering it incapable of handling complex geometry and thin walls.

It is important to note that this limitation is common to all mold makers. Therefore, the use of steel molds is imperative for molding complex parts.

Surface Finish Options

Steel molds provide greater flexibility for surface finishes, as the high-density nature of steel allows for a wider range of texture options. Steel inserts can be added to achieve custom, tall, or deep details in the tooling. Conversely, the number of possible surface finishes with an aluminum mold is limited, and custom finishes are not available. This discrepancy is due to the mold material, and is a universal limitation affecting all mold makers.

Ease of Modifications – Steel Molds vs Aluminum Molds

Steel molds offer the ability to modify and repair after initial tooling, while aluminum injection molds are not repairable or modifiable once the initial design is complete. Steel molds can be altered using welding, making it possible to modify the mold if a part redesign requires more or less plastic in a specific area. This is not possible with aluminum molds. Therefore, if there is any chance of design revisions that require mold modification, it is recommended to use a steel mold. Additionally, steel molds can be repaired in certain instances, which can save customers thousands of dollars by avoiding the need for a new mold.

Defects of the Final Plastic Parts – Less Flash with Steel Molds

Flash occurs when plastic injection material seeps into the mold seams during the injection process, and the excess material must be removed in post-processing. The cost of post-processing can be high, depending on the amount of flash and the effort required to remove it. Aluminum molds are more susceptible to flash in injection molding. This is due to the softness of aluminum, which makes it easier for the injected material to leak out of the machined cavity. On the other hand, steel is a harder material that reduces the likelihood of flash. Steel molds are less prone to deformation than aluminum molds, making them less susceptible to flash.

Steel Molds Can Handle Aggressive Materials

The lifespan of an injection tool can be affected by the material used in injection molding. Aggressive materials such as ASA/glass-filled Nylon and Ultem can shorten the lifespan of injection tools. Steel injection tools can be heat-treated to become highly durable and withstand these aggressive materials. This heat treatment enables steel tools to handle aggressive materials without any issues. However, aluminum injection tools cannot be hardened and thus cannot withstand the high injection pressure and temperature required for these aggressive materials. Therefore, aluminum injection tools are not suitable for molding such materials.

Durability – Steel Molds vs Aluminum Molds

An aluminum injection mold will hold up for short part runs and is an ideal choice for small orders. However, steel molds are more durable and suited for extended manufacturing runs. Aluminum molds do not have the corrosion resistance or thermal stability found in steel molds. Steel molds are also better able to resist the constant wear and tear of the injection molding process. These characteristics allow the steel injection molds to achieve higher production cycles and withstand non-conformities in the product. Aluminum molds must be anodized or plated with nickel to reach the same level of hardness as steel molds. Anodizing and plating will increase the tooling cost and negate the benefit of using the less expensive aluminum to machine the mold.