## Introduction: Concrete LEGO

How to make your own 10:1 scale LEGO brick out of concrete!

You'll need:
• 4 - 5 liters of concrete (when mixed)
• Some scrap wood
• Saw
• Hammer and nails / screws and screwdriver
• Ruler (or something else to take measures)

## Step 1: Messure Up!

So, how large is a LEGO block?

These links ought to give us some clues..:
http://nobsjustabs.wordpress.com/2009/03/24/converting-lego-measurements-to-scale-lengths/
http://stason.org/TULARC/games/mindstorms-lego/13-Material-Technology-and-Measurements-Lego.html

To make a 3 x 2 brick we get the following measurements:
Height of block: 9.6 mm
Width of block: 15.9 mm
Length of block: 23.8 mm
spacing of knob centers: 8 mm
Diameter of knobs: 5 mm
Height of knobs: 1.7 mm

To scale this up, we just change "mm" to "cm". Easy, huh?

10:1 block:
Height of block: 9.6 cm
Width of block: 15.9 cm
Length of block: 23.8 cm
spacing of knob centers: 8 cm
Diameter of knobs: 5 cm
Height of knobs: 1.7 cm

## Step 2: Building the Frame

Remember that you want to be able to disassembly the molding box after the concrete has set, so dont go overkill with the size of the nails. (Or, just use screws instead)

1) Start out with a peace of wood that is approx. 18 x 26 cm and drill out the six 50 mm holes using a hole saw.

2) Nail another 18 x 26 cm peace of wood to the underside of the previous one.

3) Add the 96 mm high walls to complete the jig for molding.

## Step 3: Molding

1) Follow the instructions on the bag of the concrete on how to make the proper mix. You will need at least 4 liters.

2) Fill the box up.

3) Why not add a copyright infringing logo to the wet concrete?

4) Set aside for a few days or what ever the bag of the concrete states, in order for the .

5) Carefully remove the box, starting with the sides and the "bottom".
To remove the wood with the six holes, its easiest to try to break the wood apart. Carefully.

6) If you chose to paint it, use the proper paint!
Candy red would probably look sweet!