Hydration beads, floral bead, water beads, polymer beads are all the same thing. Typically used in fancy floral arrangements, these wonderful hydration beads have the magical ability to absorb water. They can hold water for several days before they dehydrate. Toss them in water to re-hydrate to use them again. Here, I'll show you how to use these beads to make a really simple cooling band.
Step 1: Materials
The most important item that you are going to need to find are the hydration beads. They can come fully hydrated as shown in the photo, usually in the floral section. You can also find them dehydrated in small packages. If you can find them hydrated in a jar, you should just need one (you'll need at least two packages if you find them dehydrated).
You will also need a bandana and a sewing machine.
Step 2: Dehydrate
If your hydration beads are already hydrated, your first step is to dehydrate them. Lay them out on a flat surface and allow them to dehydrate. It will take about a week to fully dry out. As you can see in the photo, there is a huge difference in size!
If you have found dehydrated beads, bonus! You can completely skip this step.
Unfortunately most that are sold are already hydrated.
Step 3: Lay Out Your Bandana
Take out your bandana and fold it in half. Here, you could cut it narrower, or leave it as is.
Step 4: Sew in and Lock Pockets
Next, sew in some pockets (3cm wide), put in about a teaspoon of dehydrated beads, and sew the pocket shut. Sew the seams at least twice so that the beads stay locked in.
Step 5: Soak in Water
When you are ready to activate the band, toss it in the sink or a bucket of cold water. Leave it in there for 15-20 minutes to allow the bead to fully re-hydrate. Now you are ready to wear!
When you are done using your band, leave it out in the open to dehydrate fully. When dehydrated the beads will return to their shrunken state. To reactive toss it back in water.
Wear around your neck, head, arms, wherever! Stay Cool!
Step 6: Cooling Power!
MartinPhx had asked about the temperature difference of the cooling band. So I've done a little experimenting.
The outside temperature is 41C or 105.8F at 100% humidity (the temperature is including the humidex). To accurately measure the limits of the band, I selected a very hot surface. In this case the chair came to 52C or 125F. Placing the DRY DEHYDRATED band came to 41C or 105.8F. After hydrating the band for 20 minutes, and allowing the excess fabric moisture to evaporate, the temperature was 28C or 82.4F. Moving the band to another location in the shade brought the temperature down further.