Since 2009, TOPBATH’s manufacturing base in Foshan, China, has been producing bathroom products for over 60 export markets. For importers and project contractors, understanding how a product is made is the best way to assess quality and consistency.
In this first edition of our Factory Journal, we are pulling back the curtain on our most labor-intensive product: the Stone Resin Freestanding Bathtub.
Step 1: Mold Preparation
Unlike acrylic, which is vacuum-formed over a shell, stone resin is cast. Every bathtub requires a precision-engineered mold. Before casting, workers apply a specialized release agent to ensure a perfect demolding process.
Step 2: Casting and Curing
Our proprietary mix of natural stone powder and resin is poured into the mold. This is where the tub gets its solid, heavy feel and excellent heat retention. Once poured, it must cure for a specific time to ensure the material hardens uniformly without structural weak points.
Step 3: Hand Polishing (The Critical Step)
After the tub is pulled from the mold, it undergoes an extensive hand-finishing process. Workers use progressively finer grit sandpapers to achieve the signature matte, velvety texture that designers love. If this step is rushed, the surface will be uneven or prone to staining.
Step 4: Overflow and Drain Installation
We pre-install the overflow and drain outlets according to the client’s specification (e.g., pop-up drain vs. cable-driven). Every fixture is sealed and pressure-tested to prevent leaks after the container is unloaded.
Step 5: The 100% Water Test
We don’t just inspect visually. Every single TOPBATH tub is filled with water to check for overflow leaks and balance. For project buyers, this step means you can safely install units directly from the container without paying contractors to conduct water tests on-site.
Step 6: Packaging for Export
An excellent tub will fail if it gets cracked in transit. We use custom-molded foam lined with thick cardboard and wooden crates, protecting the tub against the drops and vibrations of ocean freight.