Introduction: DIY Concrete Hegagon Coaster

About: In Love with design, engineering and science. Please check out my Instagram page @zacsdesigns_ Feel free to request a project and ill see what I can do. I also sell a range of products so inbox me on my accou…

What inspired me?

Well, I love obscure, weird and impractical materials such as concrete while incorporating the material into a project where its features, properties and function isn't required. I love concrete as its such an industrial material and has a very smooth finish.

What will you need?

- Concrete mix or cement and sand

- Water

- Duplex board

- Pencil

- Ruler and compass

- Scissors

- Hot glue gun and hot glue sticks

Step 1: Making the Mould

Step one - Making the mould

To make the mould, grab a sheet of duplex board and using your compass, draw a circle with radius of 100mm. When this is done, mark onto the circumference every 52mm. You should have five marks. When you have this, join all the lines to the centre. Now, look at the picture and complete that on your net so far.

When you have completed the net. You now need to use hot glue to secure it in place. Remember to really seal it as you dont want flashing to occur.

Step 2: Mixing the Concrete

Step two - Mixing the Concrete

Before you mix in the sand with the cement and water, it's best to mix the cement and the water. First, place the cement mix in the container. Add about 20ml of the water in small intervals, this will allow you to ensure you dont make any errors.

Its now time to add the sand. Never put in all of the water in one go. You will need to add about 100g then stir. Complete this step until the mix becomes like cookie dough. If you add too much or too little you will end up with a weak mix.

Step 3: Pouring the Concrete and Finishing Up

Step three - Pouring the concrete and finishing up

Place some of the concrete bit by bit until 1/4 of the mould is full. Tap gently just to release a few bubbles caught in the bottom. This also helps the concrete spread. Place more of the concrete mix into the mould until it is half full. If there are still gaps, tap the mould on a desk. The concrete needs vibrating before setting as it ensures the mould if definitely covered.

After a day or two, it's ready to remove that mould. Taking off the mould is actually easy, just rip the card and then gently take off the residue from the concrete block.

Step 4: Finished!!


Thank you so much for reading this Instructable, even if you clicked onto the by accident thank you. Every view counts. I love these mini projects as it gives you people, my viewers a quick and simple project to try at home, please feel free to comment, follow and favourite for more amazing Summer DIY projects like this one.

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