From First Prototype to Final Form: How the Pisces Pipe Silicone Fish Took Shape

After establishing the two-fish appearance of the Pisces Pipe, we still needed to solve an important structural challenge: How could we install the glass bowl inside the silicone fish without disrupting the integrity of its fish-shaped silhouette?

The glass bowl needed to be easy to install and remove, while the product had to remain comfortable to hold, easy to set down, and suitable for one-handed operation. The bowl, connecting tube, and attachment structure also needed to remain as hidden as possible inside the fish-shaped body. To achieve this, we went through multiple sketches, 3D models, printed prototypes, and real-world tests before gradually determining the final structure.

Finding the Right Position for the Glass Bowl

During the early design stage, the first question was which direction the glass bowl should enter the silicone fish.

Installing the bowl from the top or side would require a relatively large opening on the visible surface of the fish. This would interrupt the continuous fish-shaped curves. An exposed mounting structure would also make the silicone fish look like a collection of separate components rather than one complete form.

We explored several bowl positions, installation directions, and fish-body structures. Each sketch addressed the same challenge: The glass bowl had to be easy to install and remove without noticeably compromising the appearance. We also had to consider how a user would hold the product, push the bowl into position, and operate the lighter with one hand.

After comparing several concepts, we decided to create an opening at the bottom of the silicone fish and install the glass bowl from below. This allowed the primary installation structure to remain hidden while preserving the complete front and side profiles. When the bowl needs to be cleaned or replaced, it can be pushed out directly from the bottom.

Once the bottom-loading direction was selected, we created two additional sketches to refine the bowl opening, internal tube channel, and fish-body proportions. The bottom-opening concept was ultimately selected as the final sketch and became the basis for three-dimensional modeling.

Prototype One: Problems Created by the Sloped Fish Body

After completing the sketches, we created the 3D model and printed the first prototype.

The first 3D-printed prototype had a sloped body, with a lower inner side and a higher outer side. We originally hoped that the variation in thickness would create greater visual depth and give the combined two-fish design a more dimensional appearance.

However, the glass bowl could not be manufactured with a sloped top that precisely matched the angled fish body. It had to use a flat design. When the flat glass bowl was installed inside the sloped silicone fish, the top of the bowl could not maintain the correct height in relation to the surrounding surface. During extended use, some areas of the silicone were positioned too close to the heated zone, creating a risk of heat damage.

The internal channel for the bowl’s connecting tube was also too low in the first prototype. Because each glass tube was attached by hand, slight variations in height and angle were unavoidable. The low channel pressed against the connecting tube and caused the silicone fish to deform slightly. Once the fish body changed shape, a large gap appeared between the fish head and the lighter, weakening the visual unity of the two-fish form.

Prototype Two: Changing to a Flat Structure

To address the problems found in the first prototype, we changed the second silicone fish to a flat structure. This allowed it to work correctly with the flat glass bowl and reduced the possibility of the silicone being damaged by heat during extended use.

At the same time, we increased the height of the internal tube channel to provide more room for the dimensional variations created during the handmade glass assembly process. After this adjustment, the tube no longer placed excessive pressure on the silicone fish. Deformation of the body was reduced, and the gap between the fish head and the lighter became noticeably smaller.

However, the channel in the second prototype was now too high. When the user pushed the glass bowl upward from the bottom, too much of its upper section extended beyond the silicone fish, affecting the overall user experience.

Prototype Three: Rebalancing the Channel Height

For the third prototype, we carefully reduced the height of the internal tube channel. The goal was to balance the manufacturing tolerances of the handmade glass bowl with the need to control its vertical movement.

After this modification, the glass bowl and connecting tube could be installed smoothly without noticeably pressing against the fish body. When the bowl was pushed upward from the bottom, its upper section extended to a more appropriate height.

The sliding connection with the lighter also worked correctly in this version. The silicone fish could slide into place along the raised rail on the side of the lighter. The gap between the two parts became significantly smaller, creating a more complete Pisces silhouette. At this point, the product entered the real-world testing stage.

Adding a Heat-Protective Bottom Cap After Testing

During testing, we discovered that the bowl opening at the bottom of the fish could occasionally allow a finger to come into contact with a heated area. To solve this problem, we decided to add a removable silicone bottom cap.

The cap covers the bottom of the glass bowl and reduces the chance of direct contact with the heated area. It also closes the bottom opening, giving the fish body a cleaner and more complete appearance.

Adding the bottom cap also required us to readjust the height of the glass bowl’s connecting tube. We moved the connection point downward to create enough space for the cap. This allowed the cap to fit naturally without changing the position of the upper section of the bowl. Finally, we added the 7pipe “7” logo to the cap, turning a functional heat-protection component into an integrated part of the overall design.

From an Appearance Sketch to a Functional Structure

From abandoning the top opening that disrupted the fish silhouette to selecting a bottom-loading bowl; from replacing the sloped body that could not properly accommodate a flat glass bowl with a more practical flat structure; and from correcting an internal channel that was first too low and then too high, every prototype addressed a specific problem discovered in the previous version.

In the final design, the glass bowl is hidden inside the silicone fish while the front and side profiles remain intact. The bottom-loading structure makes the bowl easier to install and remove. The sliding rail allows the silicone fish to connect naturally with the lighter, while the removable silicone cap addresses the heat-protection issue discovered during testing.

The final form of the Pisces Pipe silicone fish was not created in a single drawing. It gradually took shape through sketches, 3D modeling, printed prototypes, and real-world testing. A complete product design must ultimately balance appearance, manufacturability, and the user experience.