DIY Geometric Pineapple Cement Planter

Unwilling to spend much on a silicon mold straight from eBay? Well, that's me and I'm willing to use recycled materials only.

You would probably then ask where to get a small pack of cement especially when you are in somewhere remote where only large 20kg bags of cement are available in shops for large scale constructions. I would say luck is needed, especially contacts, otherwise I would recommend you to just go buy a small pack of mix cement online and wait. You might probably get a small bag for free if you ask the construction supervisor from the nearby site nicely or just scavenge some leftovers after a major construction. Well, that's just what I did for free, I did both.

Materials needed:

- Mortar / Mortar + Cement

- Water

- Thin Cardboard

- Big unused plastic container

- Plastic cup

- Big Plastic bottle (1500ml)

- Cellophane tape

- Straw

- Chopstick

- Small weighs (stones, marbles....)

- Blade, scissors, ruler and cutting board

- Sandpaper / Knife sharpening stone

- Soldering tool (optional)

1. Print mold template

I got the template from a Korean site, and since the google translate didn't help much for English readers like me, I decided to revise it and give credit. Thanks Harvey!

Here's the source to the template which is located at the bottom of the site:

https://m.blog.naver.com/PostView.nhn?blogId=hankukilbo&logNo=70171170873&proxyReferer=&proxyReferer=

Note: The PDF had to be printed in A3 size otherwise it will be too small (left image) to make the planter. So I enlarged it and viola (right image)!

2. Make cardboard mold

After simply cutting each piece of template out, simply attach the template onto the cardboard with glue and proceed with the cutting.

Score ( make a cut mark halfway ) the cardboard at the lines and fold them.

For the bottom piece of the mold, penetrate a hole (optional) with a soldering tool or a thick nail.

Hack found:

I figured out in order to prevent the cardboard mold from sticking onto the dried cement and cause a mess, I covered the inward part of the mold with cellophane tape to create a smooth texture. Don't worry, the cellophane tape won't stick to the cement.

Attach all the pieces together and make sure that the sides are zig-zagged.

Cover up the outer part of mold with cellophane tape so that water from the cement mixture won't leak out.

Then, cut the 1500 ml plastic bottle with a height higher compared to the height of the mold and make a hole at the bottom with the heated-up soldering tool (optional).

Insert a chopstick into the straw ( to make it firm) and pass both of them through both holes (tape them firmly). Make sure the inner mold do not touch the bottom of the outer mold.

Hack:

Another easier alternative is just pour the cement mixture into the mold and press in the inner plastic mold with a finger covering the hole at the bottom of the plastic bottle ( if there is one). After that, carefully insert the straw + chopstick through both holes.

3. Cement Mixing

Based on some site tutorials, mortar is sufficient.

The ratio of mortar to water is approximately (4:1), measured with the plastic cup.

That means if 2 cups of mortar is used, half cup of water is poured in. However, the water usage depends on whether a peanut butter jam consistency of mixture is obtained.

For me, in order to strengthen the structure, I added some cement (optional).

The ratio of mortar to cement to water is approximately (2:1:1).

Mix the mixture in a big plastic container and be flexible with the water usage until a peanut butter jam consistency is achieved.

4. Pour the mixture

Do be reminded to settle the mixture by shaking/ flicking the mold.

By this step, the inner mold will start to float, that's where you put some weights (e.g. stones, pebbles, marbles, etc...) into the inner mold to weight it down (make sure it does not touch the bottom of the outer mold).

5. Here begins the waiting hours

You can basically peel of the mold after 24 hours of drying. Some people peel it much earlier to get a rough industrial texture with plenty of holes for fancy display.

So the longer you wait, the smoother it gets.

6. Retouching

Hack:

Instead of using sandpaper, I used a knife sharpening stone which is much easier to handle. Don't worry, sandpaper still works just fine.

Happy Trying!