Sometimes it can be difficult to clean the insides of containers like vases and fish tanks. Many flower vases have an opening that is too narrow to fit your hand through and a shape that makes it inconvenient to use a brush. With a fish tank, you often have to drain the tank in order to clean the glass. Both of these problems can easily be solved with a simple magnetic scrubber. All you have to do is embed a strong magnet inside a sponge or other scrubbing tool. Then you can guide it with another magnet on the outside and clean even the most difficult to reach places.
Step 1: Select a Scrubbing Tool
The first thing that you need is a scrubbing tool. The ideal thing to use is a sponge. Since the magnetic scrubber that we are making is reversible, you can use a sponge with a course scrubber pad on one side and switch between the two sides as needed. You can also use tools like a magic eraser but these will degrade much faster than a sponge.
Step 2: Select a Magnet
You need a strong magnet to be able to firmly hold the scrubber to the inside wall of the container. I recommend using rare earth magnets such as neodymium magnets. You can purchase these at most hardware stores.
Step 3: Cut the Scrubber to Be a Little Larger Than the Magnet
Take your scrubbing tool and cut it so that it is a little bigger than the magnet on each side. You want the magnet to be able to fit inside the scrubber but you don't want it to be too big.
Step 4: Cut a Slot in the Side of the Scrubber
Use a sharp knife to cut a slot on the side of the scrubber that is big enough for the magnet. You want the magnet to rest in the centerof the scrubber. Be careful not to cut all the way through. The easiest way to estimate the depth of a cut is to hold the blade up to the front face. This will show you how far the blade will reach.
Step 5: Insert the Magnet
Insert the magnet into the scrubber. You now have a simple magnetic scrubber. We need two of these so repeat the previous step to make a second one.
The two magnetic scrubbers should be able to attract each other from several centimeters away.
Step 6: Use the Magnetic Scrubber to Clean the Inside of a Container
Place one of the scrubbers on the outside wall of the container and then place the second scrubber inside the container. They should immediately pull towards each other and hold themselves firmly against the side of the container. You can then move the outside scrubber and the inside scrubber will follow.
If the inside scrubber comes loose, just move the outside scrubber close to it and the inside scrubber should be pulled back to it.
The only problem with this design is that the magnet can sometimes slide out of the side of the sponge. This can happen if you pull the scrubber in the direction of the cut slot. You can avoid this problem in two ways. You can move the scrubber only in the direction opposite of the slot or you can just sew the opening closed.
Step 7: Optional: Sew the Opening Closed to Hold the Magnet in Place
To prevent the magnet from sliding out of the opening in the side of the scrubber, you can simply sew the opening closed. First make sure that the magnet is centered. Then using a needle and thread sew the two sides of the opening together. It doesn't matter what kind of stitch you use as long as it holds the magnet in place.
Step 8: Optional: Make the Magnetic Scrubber Stronger
If you would like to make the magnetic scrubber stronger, there are several things that you can do.
One way that you can do this is to make the magnets stronger. You can do this by using larger magnets. You can also use multiple magnets in each scrubber.
Another option is to simple bring the magnets closer together. You can do this by using a thinner sponge. You can also cut the slot closer to one side.