How Not to Build a Reflection Pool With Galium




About: Hello! I'm a Double major in computer and political science, I like long walks in the beach. I believe in unicorns and magical lands like Narnia and Hogwarts. Thanks for reading!


This is an introduction of how not to build a reflection pool with gallium!

The first couple of steps was to demonstrate the beginning steps however in the end I will document the mistakes I have done and what you should not do.

The original idea was to build a similar contraption of a liquid mirror. The liquid would spin and create a parabolic body. This is using a centrifugal force to focus light into one center.

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Step 1: Step One Get Gallium

Gallium is easy to obtain from Amazon or Ebay. However, a real liquid mirror uses a large mercury pan. Mercury was not available and also very hazardous so Gallium was the safest material to use.

Step 2:

Melt the gallium out of the tube. How I did this was get hot water and partial melt the gallium so it would slide out. Afterwards use a mini torch to liquefy the rest of stick.

Step 3:

Torch the surface a little bit. The problem with gallium is that slag resides at the top due to oxidation. You can tell the difference between untorched and torched. You can also stir it with a toothpick to make it more visible.

Step 4: The Problem

Since the gallium needed to spin at a rate where it was controllable I used a dremel to adjust the rpm.

Step 5: The Problem Two

After having a bit that would fit on the bottom of the glass. Attached via using resin, my next step was to try it out.

This is where the failure began.

The cup detached when approaching to the lowest RPM. The rpm was too high and the cup was flinged outwards. Thus the hole in the picture.

Step 6: Conclusion

The whole project cost a tad bit of money however lesson learned. When building a pool that needs to be spun the rpm has to be low and adjustable. A dremel is not sufficient and thus another approach is needed.

Any comments and ways to accomplish this is greatly appreciated. Thanks for reading.

Here is a successful attempt in this process.

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    6 Discussions

    Arty Marty

    3 years ago

    I have an idea of how to stop the slag forming.
    Just a thought experiment.
    As the slag is caused by oxidisation, you can use argon gas to prevent it. Argon gas is non reactive and also about 35% heavier than air. If you made a box to put your spinning contraption in and filled that box with Argon, it would displace the air (oxygen) and so the gallium would not oxidise.

    The box can be open at the top for access while you do your thing as the argon will fill it and sit there. Imagine it like water - so no sudden moves in the box with your hands because you'll "splash" the argon out. Also like water, argon is non toxic, however you need oxygen to breathe, so take care you don't "drown" in the argon. If you breathe it in, you'll have that in your lungs instead of oxygen and that won't end well. So take care, don't stick your head in the box!

    Something to think about :)

    1 reply
    JentlemenArty Marty

    Reply 3 years ago

    Your comment is well appreciated comrade. I shall try Argon then. :)


    3 years ago

    Don't us a torch to melt the metal. Gallium is relatively inert at room temperature but oxidizes rapidly at higher temperatures. Teh flame of the torch can easily be at 1000F. Where the flame touches the gallium you will get corrosion. Melt the metal slowly with an electric heaters. Don't use a metal or glass dish. Gallium is a powerful solvent of metals and will wet glass easily. If metal or glass mix with it a slag may form very quickly. Try a PTFE, teflon, or polyethylene containers instead

    1 reply

    Reply 3 years ago

    Your comment is well appreciated comrade. I haven't thought of that I shall try it.


    3 years ago

    Try a box fan and hotglue to attach your bowl. A variable power supply should let you dial in the speed you want.

    1 reply