These striking candle holders have a rugged yet elegant shape, and are a great addition to your outdoor area, or on your dining room table. The delicate shape is made from using a balloon as a mold to cast concrete, creating an unusual shape. Each mold will be unique, and there's no limit to the shape variations you can achieve with this method of casting.
Let's get casting!
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Step 1: Setup
Most concrete bought from the home store will have aggregate, since that's what gives concrete it's compression strength. For this project we'll want to remove the aggregate to give a smooth finish, and because there's no need for any compression strength from the aggregate since these candle holders won't be under any load.
Removing aggregate was discussed in detail in my free Introduction To Concrete class. Sieve the concrete to remove all the large and medium aggregate, leaving the cement and small aggregate.
The only other supply you'll need for this easy project any type of balloons.
Step 2: Balloon Support
To hold the balloon as we work on it we'll use the saved aggregate that was sieved earlier in a cup to act as a weight, the balloon will be held down by this weighted cup and make it much easier to work on.
I made a few concrete balloons so I portioned the aggregate into 3 cups. I find that disposable cups are best for messy projects like concrete, that way there's no fuss with cleanup.
Step 3: Secure Balloon
Inflate a balloon as large as you like and tie off the end.
In order to cover the balloon with concrete it will need to be secured so it doesn't move around. Orient the balloon so the tied end sits inside the cup with ballast prepared in the previous step, then secure it in place with a small piece of tape from the balloon to the cup.
Step 4: Apply Concrete to Mold
The easiest way to work with concrete and unusual molds is to use your hands. There's no tool that can match the dexterity and familiarity of your fingers, just make sure to wear gloves, as concrete will burn skin.
Gently plop gobs of cement on the top of the balloon, then tap the balloon to settle the concrete and spread it out.
Continue adding more concrete to the top and tapping until the concrete starts spilling over the sides and down towards the cup.
If any small sections of concrete start creeping faster than others you can carefully push it back upwards to prevent it breaking off. However, there really is no wrong way to do this, so let your design take whatever shape you like.
After concrete application let cure overnight.
Step 5: Remove From Mold
The balloon mold is thin and has a large surface area, so the concrete cured fast.
The balloon has pulled away a little from the cured concrete casting, and you may be able to pull the balloon out. However, it's easier to remove and less likely to break the fragile casting if you just pop the balloon.
Wear a face mask and eye protection, as the balloon can spray fine particles when it pops.
Step 6: Clean Inside of Mold
After removing the balloon carefully clean the inside of the concrete candle holder with a damp cloth.
Be gentle when handling the thin concrete castings, even though they are concrete they are still fragile. Even if a small portion of the candle holder breaks off it won't really matter, the irregular sides and organic shape of the concrete lends itself to minor mishaps.
Step 7: Paint
Painting the insides is an optional step, but will really elevate the look of the piece. From a functional perspective, lighter colors will help reflect light and make the concrete candle holders look even brighter.
I like the idea of glowing orbs in my garden, so I chose a metallic brush-on acrylic paint for my candle holders. Spray paint would also work. Any metallic or glitter paint would be a great choice for the interior paint
I had a few color choices on hand, so decided to try gold and bronze colors.
The last step is to add tea lights to each candle holder, depending on how large your casting is you might be able to fit 2 or even 3 tea lights inside and really boost the brightness.
Though these candle holders are fun any time of the day, they really stand out when the sun goes down.
Step 9: Wrap-Up
Using a balloon as a mold for concrete is deceptively simple, yet has a very big payoff. This is true for a lot of unusual molds for concrete, and this is just one example of how you can use everyday items as a mold to hold and shape your concrete as it cures. If you liked this project, be sure to head over to the free Concrete Class to find out what other great things you can do with concrete.
Happy making! :)
Did you make your own concrete candle holder? I want to see it!
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