How are Walk in Tubs made?
How a walk in tub is made varies depending on the manufacturer. It also depends on what the tub is made of. Many manufacturers construct their walk in tubs with fiberglass because it is cheaper and can be easier to use when constructing a walk in tub due to the depth of walk in tubs. A walk in tub made of acrylic can be harder to construct as it is much more complicated to form a deep basin with a chair height seat with a single sheet of acrylic.
This is a general description of how an acrylic walk in tub is constructed. Please keep in mind this process will vary depending on the manufacturer.
In general, when constructing an acrylic walk in tub you would begin by heating an acrylic sheet. The heated acrylic sheet is then placed over a vacuum mold, wherein the mold is shaped like a bathtub, including a seat and a foot well. The vacuum draws the heated acrylic sheet into the mold. Vacuum pressure is manually reduced when the acrylic reaches the top of the seat in the mold, and the vacuum is shut off when the acrylic is approximately two inches from the bottom of the foot well of the mold. A mold release agent may also be sprayed onto the mold to facilitate the movement of the acrylic over the surface of the mold. The acrylic is cooled and removed from the mold and reinforced with fiberglass. The tub is then secured to a steel support frame. A door space is cut in the side of the molded acrylic tub to allow a person to step into the foot well of the tub from the side without having to step over the walls of the tub. A pre-hung door assembly is then installed in the door threshold.
The door itself can be comprised of two main pieces. In this case, the threshold piece is vacuum formed to fit within the door threshold in the side of the tub. After the threshold piece is vacuum formed, it is trimmed from the web. The second piece of the door is a flat panel that simply covers the indentation of the threshold piece. The two door halves are bonded together, and the door is then sanded and painted. After that, the strike plates are added. The frame for the door assembly comprises a single aluminum piece that is extruded and shaped to fit the edge of the door threshold. The extruded frame includes a channel for a rubber gasket that forms part of the tub's water seal. After it has been shaped, the extrusion is powder coated and mounted onto the tub. The frame is secured to the threshold with a waterproof adhesive. The frame is then secured to the tub by a retaining screw to supplement the adhesive.
After the door frame is securely in place, the hinges of the door are aligned and attached to the frame and door. The frame includes a track on the outer edge that is specifically dedicated to mounting the hinge.
After the door is mounted, a gasket is inserted into the seal track of the frame. The gasket helps form the water tight seal of the door. Caps are added to ends of the aluminum frame which shows a finished tub and door.
Finally, the handle base is fastened to the tub. The handle is then fastened to the base.
The door in this description is similar to a regular pre-hung door that would be found in a house and can be installed into the tub as a separate, pre-assembled unit. Some walk-in tubs have the door attached directly to the side of the tub, which is analogous to mounting a house door directly to the wall. The extruded frame used in this description provides structural integrity to the tub and insures proper alignment of the system as it is contained as one unit. The frame keeps the walls of the tub from flexing, and the dedicated hinge track helps keep the door aligned, thus maintaining the integrity of the water seal. In addition, the frame improves the door seal by providing a dedicated track for the gasket.
Please keep in mind that this is a general description of the construction of an acrylic walk in bathtub. To find out the specific construction details of a walk in bathtub that you are planning to purchase be sure to contact the manufacturer of that specific tub.