Streamlining Automotive Lock Development with WayKen’s Expertise

Project Background

With the automotive technology development, automotive locks have evolved from traditional mechanical locks to electronic and intelligent locks, also increasingly meeting the diversified and personalized needs of users.

Automotive locks typically include car door locks, wheel locks, engine locks, steering wheel locks, and transmission/shift locks. These locks are made up of typical components such as the lock core, locking body, locking tongue, and clasp, as well as modern features like electronic controls, sensors, remote key fobs, and alarm systems.

As a trusted rapid manufacturer in the automotive industry, WayKen has collaborated with many well-known car brands. In this case, our client has designed a new car lock and is currently looking for a supplier to manufacture 15 sets of lock body components for testing. This article will show you how WayKen efficiently handles such projects and ensures high-quality results.

Analyze Project Requirements and Custom Machining Solutions

The materials commonly used for making automotive locks include copper, aluminum, carbon steel, stainless steel, zinc alloy, engineering plastics, etc. Copper is used to make lock cylinders due to its high strength, excellent impact resistance, and corrosion resistance, while other materials are used to make other components. However, the customer is innovatively using ZAMAK5 for the lock body.

In this project, most of these parts are relatively easy to process. However, the stator and solenoid cam are relatively difficult to manufacture. They are composed of ZAMAK and PP, with PP covering the surface of ZAMAK. It is challenging to assemble them together like the 3D model after processing them separately.

Traditional Manufacturing Limitations

Traditionally, there is the die-casting mold to make the ZAMAK5 lock parts first, followed by injection molding to wrap the PP around them. However, as the client’s design is still under development, this method is inflexible and costly, especially if the design changes in the future.

WayKen’s Flexible Solutions

To address these limitations, WayKen proposed a machining solution that uses CNC machining the zinc parts and wrapping the PP-like resin around the ZAMAK parts by vacuum casting (2k molding) instead of injection molding. Such a flexible way can save the time and cost of mold making, and using silicone mold instead of injection mold can also save the extra investment by the design modification.

How to Start Manufacture Car Lock Components?

In this section, we will focus on the “stator” component mentioned earlier. The manufacturing steps are as follows: first, we produced the car lock body – ZAMAK part and then machined the plastic parts.

Metal Part Manufacturing

To ensure efficient CNC milling, we need to clarify the ZAMAK5 and its machining characteristics to rationally select tools, cutting fluids, and machining speeds.

• Gelatinous Behavior: Zinc heats up quickly during machining, causing it to “gel” and adhere to the cutting edge of the tool. This increases tool wear and reduces cutting efficiency.
• Low Melting Point: The low melting point of ZAMAK5 means that high feed rates could cause excessive material shear, limiting the cutting capabilities.
• Brittleness: While some high-aluminum ZAMAK grades are ductile, their brittleness can lead to chipping issues during machining.

Challenges of Machining Stator’s Metal Body

The stator’s complex metal structure requires multi-surface machining. A common cost-saving solution is to use jigs and machine it multiple times on a 3-axis machine. However, this method introduces several issues:

• Positioning Tolerances: Multiple setups on a 3-axis machine can lead to new positioning tolerances, affecting the precision of the part.
• Cumbersome Clamping Process: The time-consuming clamping process, including repositioning, tightening, and tool setting, reduces machining efficiency.

Optimized Machining Solutions

To address these challenges, we decided to use a combination of 3-axis and 5-axis machines to improve accuracy. We first mill the round bottom end face on the 3-axis machine, using it as a datum for positioning. Then, the remaining features are machined on the 5-axis machine.

While CNC milling was effective for most features, the stator’s deep cavity presented a challenge. With a bottom width of only 2.2mm and a depth of 66.5mm, the tool could not reach this area. To address this, WayKen used EDM to create the deep cavity, which ensure the assembly of the stator.

2K Molding for the Automotive Lock Component

After machining the stator part, we move on to overmold the UP 5690 plastic material to the ZAMAK part using 2K silicone molding. The steps include:

• Making Master Model: We first create a complete master model, consisting of both metal and plastic parts, to be used for silicone molding.
• Silicone Mold Creation: The master is then covered with silicone, which is cured to form a mold that serves as the negative structure of the master.
• Part Placement: The ZAMAK5 part is placed into the silicone cavity, leaving space for the UP 5690 casting.
• Vacuum Casting: We put the liquid UP 5690 resin into the cavity, allowing it to cure, and then remove the finished part.

In this way, WayKen successfully completed the project and delivered the car lock components to our customer.

Feedback

After receiving the parts, the customer said, “They look great! You’ve excellently replicated and simulated the process and effect of future mass production. So far, everything is proceeding smoothly during assembly and testing.”

WayKen specializes in custom manufacturing, offering a one-stop shop from prototypes to low-volume production. With over 15 years of manufacturing experience and a wide range of machining services, we guarantee precision and quality in every stage of your project. If you have any machining requirements, don’t hesitate to get in touch with WayKen!