Introduction: Cheap Ripple Tank

About: I have a master's degree in physics and my hobbies are: 3D printing, CAD design, arduino, astronomy, astrophotography, cosmology and sci-fi :)

- 2x extension springs (you can rubber bands as alternative)

- 2x 4mm banana sockets

- 2x pieces of wood (170mm x 20mm x 10mm)

- NOTE: 3D printing file available as an alternative

- 3V DC motor

- M3 bolt with nut

M5 round headed bolts 40mm long

- Servo arm

- Wire

- 4x screw eye hooks

- Tool clip (make sure to buy same diameter as your DC motor)

- LED strobe light

- A4 3mm perspex sheet

- PLA for 3D printing


- Wire cutters

- Sand paper

- Solder and soldering iron

- Screw driver (Philips and/or flat)

- Glue ( Gorilla super glue is fine)

- 3D printer

Step 1: Assembly Step 1

- Mount M3 screw on servo arm

- Mount servo arm with M3 bolt on DC motor (this is our vibration generator)

NOTE: You can use anything to generate vibrations, as long as it's off center)

Step 2: Assembly Step 2

- Drill 2x 10mm holes in one one of the wooden block (or you can 3D print it)

- Insert 2x 4mm banana terminal sockets into the holes you just drilled

- Solder wire from terminal sockets to DC motor (see picture above)

Step 3: Assembly Step 3

- Screw M5 round headed screw to the bottom piece of wood (you may vary the distance between them to vary generated waves)

- Mount extension springs between eye hooks (see above picture)

- Screw tool clip in the center of the bottom bar

- Put motor with off center mas into clip

Note: You should have two wooden bars. Top one with 4mm banana sockets and bottom with DC motor in the center. Both wooden bars should be connected with extension springs (see picture above).

Step 4: Water Tank

Here you have two options. You can either buy some cheap clear container form DIY store on internet or you can use clear perspex/acrylic sheet and 3D print frame and legs.

NOTE: A4 size 3mm perspex works great and you can scale the frame if you wish to use larger container.

Step 5: Ripple Tank Performance

To make it work you have to:

- Mount two wooden bars with DC motor on a stand using clamps (standard school equipment)

- Pour water into a tank and make sure entire area is covered (usually 4-5mm layer of water is sufficient)

- Connect your DC to power supply (don't exceed 5V)

- Mount mini LED strobe light above the tank (make sure all students are OK with strobe)

- Put white paper under the Ripple Tank to increase the contrast

- Switch power on and by adjusting voltage (from 2V - 5V) change the speed of the motor

- Adjust the strobe light and try to make wave stationary

NOTE: With strobe light you can make wave stationary and if you use graph paper you can calculate wavelength. Then without strobe light you can try to measure speed of waves by counting 20-30 crests and measuring time with stop watch.