How Does an Ice Press Work To Make Ice Balls and Diamonds?

If you’re an avid lover of cocktails, you’ve probably heard of an ice press or even seen one in action. The way it's able to seamlessly compress ice in seconds into a spheres, heart or star shape looks like pure magic, but how exactly does an ice press work?

To make ice balls or diamonds, an ice press works by using gravity and a thick body made of aluminum—which is an excellent conductor of heat. The heat in the aluminum quickly transfers to the ice melting it rapidly while the weight of the presses pushes down on the ice into the mold. At the end you get a perfect shaped piece of ice.

In the rest of this article, I’ll discuss how an ice press works and how long it takes to use one. By the end of this article, you’ll know how to get the clearest ice to use in your press.

How an Ice Press Works

Let's first look at exactly how ice presses can press blocks of ice into intricate shapes so easily.

Ice presses are so successful at melting ice quickly because of the material they’re made of: thick layers of solid aluminum. Aluminum is able to conduct heat exceptionally well and is able to transfer its heat into the ice block, melting it quickly.

Aluminum is the second-best rated metal for conducting heat, ranking just below copper. As a result, it can naturally warm to the temperature of its surroundings and will often feel cold to the touch.

Interestingly it feels cold to touch not because it's actually cold. It feels cold to touch because it quickly absorbs heat from your skin which your body then interprets as cold.

Aluminum is such a good conductor of heat and that it will quickly absorb your body heat, leaving it feeling cool when touched.

When you place a block of ice into an ice press, conductive metal and gravity allow your ice to melt quickly. The aluminum transfers the heat needed to melt the block of ice, while gravity allows the press to shift downward and maintain the shape of the mold.

How To Use an Ice Press

Using an ice press is a relatively simple process and can be done in a matter of minutes.

To get started, you’ll need only two things:

A lot of ice presses come with a variety of molds, which will determine the final shape of your ice. There are many different options, such as diamonds, stars, hearts, and spheres. Be sure to have some fun when selecting which mold you like best.

Once you’ve acquired your ice press and block of clear ice, it's time to get started with pressing:

  1. Cut your ice block to a size that will fit in the ice press. It helps if the square slightly spills over the sides of the mold. This will leave space for it to melt into the correct shape.
  2. Place the cut ice into the press. Place the top back on and let gravity and heat conduction do the work.
  3. Add the ice to the drink of your choice and enjoy. Once the top has completely dropped and tiny drops of water appear from the seam, it's time to remove your ice and enjoy.

As you can see, you really don't have to be a cocktail connoisseur to use an ice press.

How Long Does an Ice Press Take To Make a Shape?

Now that you understand a little more about the science behind ice presses, you might be wondering just how long it takes to use one.

An ice press takes between 15-60 seconds to melt down a block of ice into the shape of its mold. How quickly your mold works can be sped up by rinsing with warm water beforehand. This will allow the aluminum of the press to use the heat it has absorbed to melt the block of ice faster.

It's important to note that the speed of your ice press can vary due to things such as what temperature your ice press has been sitting out in, if you run it under hot water beforehand, and if you’ve pressed multiple blocks of ice recently.

It's important to note that using too hot of water to rinse your ice press can result in your ice melting too quickly and losing its shape. It’s better to run your press under warm water or allow it to cool slightly before placing an ice cube.

If you press multiple cubes back to back, you’ll want to run your press under warm water or take a break every few presses. The aluminum of your press will eventually get very cold, which will make it work more slowly. By warming up the metal again, it should go back to functioning normally.

How To Get the Clearest Ice for Your Ice Press

You’ve probably noticed how clear and beautiful your ice is when you order a drink at the bar when compared to the milky white ice cubes that come out of your freezer. Using clear ice is always a great way to spruce up a beautiful cocktail or glass of whiskey, but can how can you make it at home?

To get the most transparent ice, you will want to use distilled water before freezing or boil the water beforehand. Using distilled water removes the impurities from the ice making it clearer.

However, you'll also need to use a clear ice maker that forces your ice to freeze omni-directionally. This pushes air bubbles to the bottom as it freezes, resulting in much clearer pieces of ice. Click here to see the best clear ice sphere makers or some of the best large clear ice trays.

However, it’s still possible to make clear ice using plain old tap water. You can do this by using the cooler method.

Simply place a small cooler full of water in your freezer for 18-24 hours. There will be a lot of cloudy ice you will need to scrape away, but the remaining ice should be perfectly clear.

Final Thoughts

Ultimately, an ice press works so well because it's made of thick aluminum sheets, which is one of the best metals for conducting heat.

As a result, the aluminum is able to quickly transfer its heat into the ice and perfectly melt it into the shape of the mold.