Cast Concrete Chessboard




About: ShapeCrete is a just-add-water-and-use, shape-able concrete that can be poured, rolled, pushed or molded in an infinite array of custom concrete designs. ShapeCrete is rolling out in hardware stores across t...

Here's an easy way to cast a concrete chessboard using square mosaic tiles.

The same techniques can also be used to cast small or even large tabletops.

Materials and Supplies:

  • 10 lbs. ShapeCrete
  • Rubber Gloves, Safety Glasses, Dust Mask
  • Galvanized Sheet
  • Ruler and Marker
  • Square Tiles
  • Spray Adhesive
  • Foam Walls
  • Clear Packing Tape


  • Variable Speed Concrete Polisher and Pads (optional)
  • Diamond Hand Pads

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Step 1: Mark It Out

Casting Surface:

For this project we used a sheet of galvanized steel. You could also use a thin sheet of acrylic or similar plastic. You can also use a piece of 1/2" thick Melamine. 3/4" sheet materials will work, but it's a lot easier to remove from the concrete if you stick with something thin.

There's a piece of plywood underneath the galvanized steel so it sits flat. It's taped around the edges to keep it from sliding around.

The tiles used here are 1-7/8" square. This is a pretty good size for standard chess pieces. Ideally the tiles are completely flat on one side.

Mark out the perimeter:

This piece is 16-3/8" square. This is the size that worked out with the 1-7/8" tiles, plus a 1/2" border.

Step 2: Glue Tiles Down

Glue the tiles in place with spray adhesive.

PRO TIP: Spray one side of the tile, press it down in place, lift it up, spray more adhesive, wait a bit, then press it back down. This is an easy way to get adhesive on both surfaces without having to spray the casting surface, which would have to be cleaned up later.

Step 3: Add the Walls

Stick the form walls in place. Here we're using 1" strips of styrofoam and double-sided carpet tape.

Put clear packing tape on the inside surface. This will give the concrete a smooth finish and will make removing the foam really easy.

Seal up any large gaps with silicone caulk.

Step 4: Decorative Aggregate and Details

We sprinkled decorative aggregate (Moonstone) into the form. This will show up on the surface when the piece is polished.

You can also stick other decorative details to the form walls like rubber stamps or decorative minerals, or in this case a fossilized ammonite.

Step 5: Cast

Mix ShapeCrete to a Casting Mix Consistency and fill the form completely.

Vibrate the form by moving it side to side and by lifting one edge and dropping it to the table. ShapeCrete doesn't need a lot of vibration to get a really tight surface, but the decorative aggregate can trap a lot of air.

Cover the piece with plastic and let it cure.

Step 6: Cure and Demold

Let the piece cure for 2-3 days.

Pry away the foam walls.

Flip the piece over and peel up the galvanized sheet.

Clean up the extra spray adhesive.

Step 7: Polish and Seal

The piece is now polished with a variable speed concrete polisher to expose the decorative aggregate. Just like sandpaper, you work up to a high polish through various grits / pads.

It's then sealed which will give it a natural satin finish and help keep it looking nice.

Step 8: Checkmate! the Finished Chessboard

A few small pieces of felt or cork on the bottom of the board will keep it from scratching tabletops.

Check out some of these great Instructables for some ideas on how to make your own chess pieces.

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    35 Discussions


    2 years ago

    Do you have an estimated cost for this board?


    3 years ago

    It seems thin to go without reinforcements.Do you think it will break if you move it too much.Also where can i find small black tiles?This is a great chessboard.

    1 reply
    ShapeCrete Mixskoko

    Reply 3 years ago

    Thanks! At this thickness it's really quite strong. It's unlikely you would break it unless you dropped it on a hard surface a few times.

    Check your local home improvement store or tile shop for the black tiles. I think these are usually sold as a sheet with a mesh backing, so you would cut them out and use them individually.


    3 years ago

    I've been looking for a way to make a chessboard for our extra large chess pieces at my local hackerspace in St. Louis, Arch Reactor, which hosts a Game Night event once a month.

    3 replies
    GeekTinkerShapeCrete Mix

    Reply 3 years ago

    I think the base of the King requires a 4 inch square for each of the 64 squares, so 32" x 32" total board space and with a border probably 36" x 36".

    ShapeCrete MixGeekTinker

    Reply 3 years ago

    To keep your project really simple you could get black and white 4x4" tiles from the hardware store or from a tile / flooring shop and glue them to a backer board of some sort.

    You could also cast them as we've done with the chessboard here, but at that size it will be quite heavy!

    chris wingate

    3 years ago

    Hi I am going to try this as soon as soon as it warms up and stops raining, what did you seal it with?

    1 reply

    3 years ago

    For a small area like these to vibrate the concrete make the mix more wet/liquid.

    Then borrow the partners vibrator( or buy new one) and apply to the edges ,this ensures air is dispelled from the mix.

    1 reply
    ShapeCrete Mixbobski_horner

    Reply 3 years ago

    Be careful not to wet it out too much as
    that will weaken the mix. Adding too muchnwater can also cause pigment
    separation if you're coloring the piece with integral pigment.

    A personal vibrator isn't going to do much on a larger form, but that
    might work for smaller objects. Just make sure to clean it after you're
    finished. An orbital sander has a bit more power, or a reciprocating saw
    without a blade.

    All you really need to do though is pick up one edge of the form and drop it down. This is called drop compaction and works really well on forms this size.

    Another way to help minimize air bubbles is to fill your forms 1/3rd full, then vibrate,
    then fill more, vibrate, top it off, vibrate and add more mix if needed. This makes a huge difference because the air bubbles have to travel a shorter distance to the surface where they pop.

    ShapeCrete MixJedi_zombie85

    Reply 3 years ago

    thanks a lot, I'm not too happy with the color, but it turned out. That's why you always make samples first.

    Jedi_zombie85ShapeCrete Mix

    Reply 3 years ago

    I think the colours work well, Id try casting some new chess pieces with the same colours see if that helps


    3 years ago

    This is so awesome! Seashell on the side adds a very nice touch. Thanks for sharing!


    Reply 3 years ago

    How can I report priclutrak?


    Reply 3 years ago

    press the "Flag" and choose.