Cardboard coffee table

Step 3 Fill in the bottom

Now, we are going to fill in the space between the existing struts with additional pieces. To save on cardboard, we are not going to make these full triangles. Instead we will have pieces that have one side the same width as the original triangles long side and enough cardboard on either side of this to glue it in place. I found about 4-5 ribs worth was sufficient.