Concept to Creation: Custom Floating Rezax Centre Caps

Incorrect Threads to Perfect Fitment: Custom Floating Rezax Centre Caps by Custom Labs

Some projects start with a design idea. Others start with a problem that needs solving.

This build came to us after a client purchased a set of Rezax wheels fitted with aftermarket centre cap hardware that simply did not fit correctly. The previous components appeared to have been based on publicly available files online, but once we began inspecting the fitment and threading, it became clear that the specifications were inaccurate for this particular wheel setup.

Rather than forcing a compromise fitment, we approached the project the way we approach all engineering-based builds at Custom Labs — by starting from zero and building the solution around precision.

The Problem: Incorrect Thread Specifications

The original setup used a threaded retention system behind the baffle plate. At first glance, it seemed straightforward, but once we measured the threads properly, we discovered the pitch and tolerances were incorrect for these wheels.

This is one of the biggest challenges with community-shared CAD files and universal wheel accessories. Even when dimensions appear close, thread tolerances can make the difference between:

• Perfect OEM-style engagement
• Cross-threading
• Excessive looseness
• Damaged wheel hardware
• Poor sealing and vibration issues

We later found files online that closely resembled the previously printed parts, which explained why the fitment issues existed in the first place. Those files simply were not dimensionally accurate for this wheel specification. Instead of modifying someone else’s geometry, we completely redesigned the system from scratch.

Measuring and Reverse Engineering the Hardware

The first step was accurately measuring the thread geometry and mating surfaces. This included:

• Thread diameter verification
• Pitch measurement
• Tolerance testing
• Seating surface geometry
• Baffle plate alignment
• Clearance for floating centre assembly movement

Because threaded 3D printed parts are extremely sensitive to tolerances, especially depending on print orientation and material shrinkage, we went through multiple prototype iterations before committing to the final design.

CAD Design and Prototype Testing

Once measurements were confirmed, the full assembly was designed in CAD. The project included:

• A precision threaded hex nut
• A custom baffle plate
• Floating centre cap assembly
• Logo mounting structure
• Gasket retention geometry
• Internal clearancing for proper seating

The thread tolerances became the most critical aspect of the project. Too tight and installation would risk binding or damage. Too loose and the assembly would lose the premium OEM-style feel we were aiming for. To dial this in properly, several sample test pieces were printed purely for fitment testing.

This stage is often overlooked in rapid prototyping, but it is one of the most important parts of producing reliable custom hardware. Real-world testing allows fine tuning beyond what CAD dimensions alone can predict.

After repeated fitment tests and tolerance adjustments, the final thread engagement felt smooth, secure, and precise.

Perfect Fitment and Functional Design

Once finalized, the completed assembly fitted exactly as intended. The baffle plate seated perfectly, and the newly designed hex nut threaded in with clean engagement and proper retention force. To further improve durability and finish quality, we incorporated a rubber gasket between the hex nut and the baffle plate.

This served two important functions:

1. Creating a proper seal between components
2. Preventing scratches or damage to the visible baffle plate during tightening

Small engineering details like this are often what separate a functional part from a properly refined product.

The Floating Rezax Logo Assembly

With the structural side completed, attention shifted toward the visual centrepiece. The client opted for a floating-style centre cap featuring a custom 3D Rezax logo finished in red against a matte black background.

The floating assembly gives the cap additional depth and creates a layered appearance that changes subtly depending on lighting and viewing angle.

Combined with the wheel finish, the result creates a clean contrast between:

• Satin metallic wheel surfaces
• Matte black centre assembly
• Gloss red raised logo details

Since the wheels are scheduled for a full colour change in the future, we intentionally avoided paint matching at this stage, allowing flexibility for the next phase of the build.

Engineering Beyond Appearance

Projects like this represent what Custom Labs is built around. Not just making something look good — but engineering parts that:

• Fit correctly
• Function reliably
• Install properly
• Protect surrounding components
• Maintain long-term durability
• Deliver premium presentation

What began as an incorrect threaded part evolved into a fully custom floating centre cap system engineered specifically for these wheels.

And sometimes, that process of refining, testing, redesigning, and perfecting is what makes the final product worth building in the first place.