This Instructable will show you how to make a Concrete Chessboard Planter.

Materials + Supplies:

Cultivation Trays (64)
Tape
Bucket
Concrete (20+ kg)
Water
Concentrated Black Paint Dye
Oil
Paint Stick or a different tool for mixing the concrete
42,4 x 42,4 cm 4 mm Plywood
5 x 41,2 cm 12 mm Plywood (4)
36 x 36 cm 30-40 mm Styrofoam
Screws (17)
Drill
Filt Feets (3)
Rawlplugs (3)
Diamond Sanding Sponge 40 Grid
Sandpaper 80 Grid
Dirt
Plants + Moss

Step 1: Tape the Holes

To prevent the concrete to pour out the bottom holes of the cultivation trays we need to put a piece of tape over them. This will couse the concrete to have a little point on the top but we will sand it down later.

Step 2: Mix and Color the Concrete

We need to make two batches of concrete (around 5kg each), one without any dye and one with concentrated blay paint dye to color the black tiles. To make the white tiles just follow the instructions on the bag of concrete. To make the black tiles I added the whole 22ml of the concentrated paint dye to the water and mixed it before adding the concrete.

Step 3: Pour and Cure

After mixing and coloring the concrete you can pour the two batches in the cultivation trays (32 each). After pouring the concrete tap the sides of the mold so all the air bubbles will float to the top. Wait atleast 24 hours until the concrete has fully hardend.

Step 4: Demolding and Sanding

When the concrete is has been fully hardend you can remove the molds from the concrete this should be fairly easy by breaking the plastic from the concrete. I first removed the dot with a rasp so it wouldn't damage the diamond sanding block. When the dot was gone I sanded the top flat with 40 grid diamond sanding block. After sanding with the diamond sanding block I sanded it with normal 80 grid sandpaper to add some texture.

Step 5: Oil the Tiles

I wasnt realy happy with how light the color of black tiles where. To make the black tiles darker I just used some oil I brushed on the tiles with a paper towel. After three coats of oil I was finaly happy with the color.

Step 6: Make the Mold

To make the mold of the container used some plywood cut to the right size and screwed it together according to the template. After making the wooden mold you need to get a piece of styrofoam and cut it to the right size.

Step 7: Mix, Pour and Cure

For the mold of the container you need to mix around 10kg of concrete. First poor the concrete about halfway in the mold then put the foam block in the middle and make sure it is level. Now you can put the rest of the concrete in via the sides. Now you have pored all the concrete you need to wait atleast 24 hours until you can demold.

Step 8: Demold

To demold the concrete container first unscrew the wooden mold. If the wood wont come of the side tap softly the wood of the side with a hammer. After the concrete is out of the wooden mold you can pry the styrofoam out with a screwdriver or knife.

To make sure the chessboard doesnt scratch the table you need to add some felt feet on the bottom of the box I added 3 so its always stable. Mine needed to be screwed in so I drilled some holes where I wanted the feet and added some rawlplugs and screwed the feet in.

Step 9: Place the Tiles

You are now done with all the concrete pouring. First add a small layer of dirt on the bottom so everything is level. First put the white tiles in then add a bit more dirt in the empty spaces next you need put the black tiles in. The extra dirt couses the black tiles to be higher so they stand out even more becouse if the dirt is wet the white tiles will darken a bit and the color difference will be tiny.

Step 10: Plant the Plants + Finish

For the plants I used some little red/green plants that are meant to go on on roofs. I removed most of the dirt from the plants so it would fit more easy between the tiles. After placing the plants you need to add a little layer of dirt on top of the roots. I also used some moss to cover up the visible dirt.

And you are finished!!!