One of the most common and crucial questions from customers is: how well do your products fit and integrate with Tesla?
“Sure our metal parts have excellent fit to Tesla. We have sold our products to all over the world.”
For aftermarket parts, this is the most fundamental requirement—if they don’t fit properly on the original car, they are no better than scrap metal, wasting both time and money for everyone involved.
To eliminate your doubts, this article will provide a detailed explanation of how we ensure a precise and reliable fit.
We previously wrote an article explaining how our Tesla metal replacement parts are manufactured from start to finish. It also briefly covered how we test-fit and adjust the parts on the vehicle.
If you’re interested, we recommend reading that article first—it will give you a deeper understanding of the concepts discussed in this one. (click to read: How Are ALSETTE Metal Aftermarket Parts for Tesla Manufactured?)
1. OEM Parts and an intact Tesla
“Why are OEM parts the first step? Can used parts be ok?”
Great question! If you’ve read the article I recommended, you probably already know the answer.
We need to scan genuine parts to obtain original, accurate data for modeling. This means using specialized software to create a precise 1:1 digital replica of the part.
Experienced designers can effectively control deviations, ensuring a smooth manufacturing process for the molds.
Used parts can be used, but only if they are completely undamaged. A deformed part introduces greater inaccuracies, which will affect every subsequent production step, leading to significant waste.
Now you see why error control is our top priority from the very beginning—not only to guarantee product quality but also to minimize costs and accelerate delivery.
What role does the Tesla vehicle play?
Similarly, we scan the entire vehicle to obtain precise fitment data between adjacent parts, including gap measurements and body lines—such as the alignment between the front and rear doors.
This data serves as a secondary verification of our initial modeling, further enhancing accuracy and preventing unnecessary errors.
2. Stamping Die
We’ve written numerous articles about sheet metal molds—you can find them on our blog page.
Molds are essential for mass production.
In the previous section, we created the digital model of the part. The next step is designing the mold, commonly known as die structure design.
A high-quality mold requires a balance of theory and hands-on experience.
If a tooling is designed purely based on theoretical knowledge, issues often arise during the stamping process—such as excessive stretch marks on the surface, material tearing, or even complete failure to form the part, rendering the mold useless.
This challenge is even greater for complex parts with large height variations, such as fenders, doors, and tailgates.
These parts test the skill of mold engineers, and without rich experience, it’s difficult to produce high-quality components.
Tesla’s cutting-edge vehicle design makes its parts more challenging to manufacture compared to traditional fuel cars.
With over 20 years of experience in the mold industry, we are confident in producing aftermarket Tesla parts that meet high standards.
3. Machines
Here, we will focus on two essential pieces of equipment: hydraulic presses and laser cutting machines.
Molds operate on hydraulic presses, and choosing the right press is crucial for achieving high-precision stamped parts.
Larger or more complex parts with significant height differences require greater pressing force. If the pressure is insufficient, the stamped part may have unclear contour lines or edge deviations exceeding 5mm.
For example:
- The rear quarter panel of the Model 3 is large in surface area, so we use a 1000-ton press to form it.
- The front fender of the Model Y has deep recesses, which also requires a 1000-ton press to ensure accurate shaping.
How to improve the precision of laser cutting?
First, let’s talk about the fixture. A well-designed fixture securely holds the part in place without any movement.
Each product requires a unique fixture specifically designed for its shape and size.
Before cutting a part, the corresponding fixture must be properly secured to prevent any shaking.
Each product also has a dedicated computer program that controls the laser cutting process.
Once the fixture and part are secured, we perform laser calibration to ensure the cutting path aligns perfectly with the part’s shape.
During the cutting process, we conduct regular checks to prevent errors that could lead to unnecessary material waste.
4. On-Vehicle Test
Excited for this step? We are too!
This is the moment of truth—the real test of our work. But before we move on to installation, we first need to assemble the complete product.
For parts like Tesla Model 3 doors, which consist of multiple small components, assembly is no easy task.
This is where OEM parts come in handy again. We use them to precisely position hinges and key mounting points, ensuring correct alignment between all components.
To achieve this, we weld custom fixtures to secure the parts in place. These fixtures contain various clamps, which ensure consistency and stability in production.
A skilled assembler needs patience and attention to detail. Through precise measurement and comparison, we maintain a tolerance of less than 1mm from the original part, guaranteeing a perfect fit.
Well, Let’s talk about installation!
1. An Undamaged Tesla
This is where our intact Tesla plays its most important role.
First, we remove the original parts—such as the hood, front fenders, doors, and trunk lid—since these exterior components must be test-fitted on the vehicle. We install both left and right parts to ensure consistency.
The installation process checks not only how each aftermarket part fits with the original adjacent components but also how two aftermarket parts align with each other—for example, the hood with the front fenders or the front door with the rear door.
2. Hinges
Hinges control the movement and alignment of auto parts.
The hood, doors, and trunk lid all rely on hinges, while fenders are adjusted using bolts.
Once aftermarket parts are installed, hinges usually allow for some fine-tuning to adjust panel gaps and body line alignment.
The smaller the hinge adjustment range, the more difficult the part is to produce—and Model 3 doors are a good example of this challenge.
A side note—a good auto repair technician must know how to adjust hinges. Whether replacing OEM or aftermarket parts, always check for hinge deformation first after an accident!
3. Adjustment
Our parts maintain gap tolerances within 0.5mm to 1mm, ensuring smooth and seamless alignment.
Typically, we go through 2-3 rounds of test fitting and adjustments to meet our quality standards—we never settle for a rough fit.
Each time we install and test, our technicians document necessary refinements and keep reference samples for future verification.
This process requires cross-department collaboration, as adjustments may involve data design, molding, and assembly.
Occasionally, we encounter new challenges never seen before—that’s when our skilled craftsmen step in, leveraging their expertise to solve problems efficiently.
5. Mass Production
Once everything is finalized, we move on to mass production.
We start with small-batch production and release the parts to the market, closely monitoring customer feedback. If no issues arise, we confidently scale up production based on market demand.
During the production, we remain committed to quality first.
Our production supervisors constantly remind workers to prioritize precision over speed, ensuring that every part meets our high standards.
So far, our customer repurchase rate is strong, and we have received no quality complaints.
With clients both domestically and internationally, our products have proven themselves in the market.
