Bucket Water Overflow Alarm

Introduction: Bucket Water Overflow Alarm

Using buckets to bath can reduce the amount of water you use, by letting you measure how much you have used, which is a pro that showers don't have. However, it can be boring to wait for the bucket to fill up, and being inattentive can cause the bucket to overflow which defeats the purpose using a bucket so here's a simple overflow alarm!



Building materials

  1. Cardboard
  2. A few sticks
  3. A metal plate
  4. 3 plastic balls (2 must float)
  5. Trash cover

Other materials

  1. Hot glue
  2. Scissors

Step 1: Building the Buoyancy Rod

This is the part that starts the reaction - it looks like a rod connected to two balls

1) The first stick will be the one between the two balls. Cut it so that it can be glued between the two balls. It should ideally press the balls to the sides of the bucket

2) Glue it in (I find it best works when hot glued first and then taped but do what works best for you)(This tip might not work if the tape doesn't stick to the ball)

3) The second stick is longer and will be used as the rod that sets of the rest of the alarm, it's size is relative to how big you bucket is, how far is it away from the tap area etc. Rule of thumb, the longer it is the better, the sound at the end will most likely also be louder.

4) Glue it to one of the balls

The whole system should form an 'L' shape.

Step 2: Making the Frame

1) Cut out two cardboard rectangles that are long enough to be over the edge of the bucket. For me, the measurements were 4 X 3 inches.

2) Make a small hole in each rectangle. Line up the rectangles to make sure the holes are also lined up (this should be big enough to let the longer part of our buoyancy rod through)

3) Take a bit of trash covering and completely cover the rectangles. This will waterproof the rectangles.

4) Hot glue them to the wall and then make a 90 degree stand prop it up better (check images)


(The following steps are optional)

You could also make a frame to better hold the cardboard rectangles. This works for me because my tap isn't too far away from the bucket and there's two.

1) Measure the distance between the two taps and trace a rectangle on the cardboard with an extra 1 cm on each side. The height of my rectangle is 3 cm but you can change it to what you'd like but make sure it's not too thin. Add two 1X1 cm square extending from the ends of the rectangle to make a handle-bar shape.

2) Measure the distance from the tip of the bucket to the top of the tap. Trace another rectangle, the height is 2/3 of the distance of the bucket to the top of the tap, the width should be larger than the width of the previous rectangles we made but smaller than the space in the handle-bar piece we made.

3) Cut the rectangles

4) Paste them together

Step 3: The Lever

This is the part that sets in motion the final section of the reaction.

1) First test: Fill up the bucket to the point you want the alarm to go off and then check at what height the large rod reaches up to (check image) and it's distance away from the wall.

2) Trace and cut a rectangle (or in my case rectangles). It's length being the length the rod was away from the wall and the width is up to you, it shouldn't be too thin but not too big as to clutter the area. The measurements for me were 12.5 X 2 inches

3) Now let's make the actual lever. Make two long and thin rectangles, my measurements were 3.5 X 0.7 inches, and then fold them in 4ths as shown. Since the cardboard is corrugated it should have spaces. This is very important for a later step.

4) Cut out another rectangle, it's length depends on the size of the third ball you're using but I used the measurements 6.5 X 2.5 inches which should be good enough for most medium sized balls.

5) Position the two brackets we made in step 3 so that the space between is the big enough for the rectangle in step 4 to fit. Glue it to the rectangle made in step 2

6) Insert a small piece of stick through the spaces of the brackets from step 3, make sure the stick is not crooked.

7) Glue the rectangle made in step 4, on to the stick that we inserted through the bracket-shapes from step 3. Offset it to one side so that the ratio is around 2:3.

8) Glue the lever at the height we measured in step 1. It should be glued so that the rod we made, makes contact with the long side of the lever. Adjust any parts accordingly.

9) Add a small rectangle at near the center of the lever (check image)

10) Second test: Place your third ball on the shorter side of the lever so that it rest on the railings and is stopped from rolling away by the small cardboard rectangle. If the shorter side goes down due to the weight of the ball do the following steps. If not, you are done with the lever.

11) Add a few pins and small objects (I used a coin), to the longer side of the lever until the shorter side of the lever doesn't go down because of the ball's weight.

12) Cut off the extra parts of the stick.

Step 4: Last Leg! and Troubleshooting

The last step was really long but on the bright side, this one is super short and fun!

1) Third test: Trip the lever and (mentally) mark the area where the ball lands.

2) Place the metal plate upside down at that area.

3) Retest and adjust!

And now the machine is complete!


1) Check that the rod is actually making contact and lifting the long side of the lever

2) Make sure the ball sits comfortably on the lever and it doesn't move until the lever is triggered.

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    2 months ago

    Funny and useful :)


    Reply 2 months ago

    Thank you