3D Printed Water Mill

Hey everyone! This is a team project between Eric Ling and Aitrieus Wright (both Mechanical Engineering students from San Jose State University) for this Fusion 360 Instructable project. In this instructable, we have made a decorative water mill suitable for both indoor and outdoor use. Inspiration for this project came from seeing water fountains of various styles, and the creative potential that comes with designing our own water mill would prove to be an excellent way to learn Fusion 360.

Required Materials:

• Access to a 3D Printer
• Fusion 360, and a system that can run it
• Slicer Software (ex: Cura, Creality Slicer)
• PLA (or a 3D Printer Filament of your choice)
• Bearings
• Glue (ex: Hot Glue, Crazy Glue, Epoxy, etc.)

Optional Materials:

• A Phillips or Flat Head Screwdriver
• Screws
• Plexiglass (Water Shield)

When beginning this project, the first aspect that we considered was the design of the water wheel itself. Factors we had to consider included the number of flaps on the wheel, the design of each flap, the size of each flap, and the size of the wheel itself. We also had to ensure that a bearing would fit onto the axle of the wheel (to allow the wheel to rotate more easily). In the case of our water wheel, we decided to implement 16 flaps, which was done by sketching a circle on the “right” sketching plane (this was to create the inner barrel of the water wheel. Next, we would sketch the side profile of one flap and dimension it, then use the circular pattern tool to replicate this flap profile around the circle that we had created in the center. To mount the wheel to the base of the water mill, we also created rims that would have axles where bearings could be fitted, and these axles and bearings would allow the water wheel to rotate freely when on the base of the water mill. The base of the water mill would also contain water as it flows off of the water wheel.

Next, we had to consider where the water would flow as it runs off of the wheel. For our design, we decided to create a basin for the water to flow into. What we initially had planned was for water to be pumped from the bottom reservoir/channel to above the water wheel, where it would flow down, turning the wheel, and falling back into the channel to be pumped again.

Consideration also had to be given to how the water wheel would be mounted to the basin, and where this mount would be. For this project, we had implemented two posts that could accommodate the axle of the water wheel as well as the bearings that would be placed on this axle. For ease of assembly, these posts would have cutouts where the axles and bearings could be inserted from the top. It was also crucial to have the posts tall enough to account for the wheel’s diameter and have the wheel suspended over the basin for water that runs off of the wheel.

For our water mill, the pump would be located underneath the water wheel (since the pump we used was designed to be submerged in water), so we had to ensure that there was enough space within the channel to house it. We also created a bracket where the pump’s outlet pipe would be fit into. This pipe mount is on top of the water wheel, and ensures that water flows from the bottom channel back to the top of the water mill.

This can be anywhere, on the bottom water reservoir, or on the spinning wheel itself. For our watermill design, we placed ASME and Autodesk logos on the rims so they would be visible on the left and right sides of the watermill. Decals can be added to your design by finding an SVG (scalable vector graphics) of your chosen decal, and then importing it into Fusion 360, or you may also import images into your design and trace them using the sketch tool so you can extrude or extrude cut them on your watermill.

This helped us plan how we would assemble our water mill when all of the parts were printed. In Fusion 360, this would be achieved through the “Joints” feature, and we used the “Revolute” and “Rigid” joints, but this process would be different for other CAD programs. It is possible to insert all of the parts of the watermill individually and combine them with joints in a single assembly design, but we decided to create one design featuring an assembly of the water wheel, rims, and bearings, and then adding this to another assembly consisting of the water mill basin and pipe mount.

Export all parts as STL files, this can be done by going to “File” -> “Export” -> “Type:” -> “STL Files (*.stl)”. After exporting all Fusion 360 parts as STL files, import all parts into Cura, or the slicer of your choice. Here, we can make any necessary adjustments to the parts so the 3D printer can successfully print them. Our slicer of choice for this project was Cura, and to import the STL files from Fusion 360 we dragged each STL individually and dropped it into Cura. We also used most of the default settings in Cura, but set “Build Plate Adhesion” to “Skirt”. After this, we exported the Cura project as Gcode by clicking “File” -> “Export…” -> then selecting “G-code File (*.gcode)” for the file type. Remember to name your file as well! From here, locate the Gcode file and send it to your 3d printer to print.

Assemble the parts as you did in your Fusion 360 assembly. For our water mill, we first glued the wheel to the rims, and then glued the bearings onto the axles protruding off of the rims. After letting the glue dry, we then placed the bearings and axle on the water mill channel (inside the mounts of the channel), and the pump inside the water mill. The pipe of the pump can be fitted after screwing down the pipe mount onto the back of the water mill. The manufacturer gave an incorrect dimension for the tubing, so we improvised and designed a separate method of mounting the tubing. We have included below an updated tubing mount. You can mount this on top of the previous tubing mount and use the old design to hold an LED.

After initial testing, the water mill wheel was spinning so fast that there was a lot of water splashing off of it. Because of this, we utilized plexiglass as a water shield that didn't affect viewing the water mill. We would definitely recommend this to anyone who chooses to recreate this project.

We would like to scale up this project to a larger scale where a significant amount of electricity could be generated, as at this scale negligible amounts of energy would be produced. Furthermore, we anticipated this in our original design. If you would like to scale this model up, we have included a support bracket to hold a motor that could connect to the axle/rim. The axle of the rim already has a hole intended to connect to the shaft of a motor.