Make a mould First you need to make a mould for your canoe -- a positive mould where the canoe is moulded over the outside, not in a hollow. Glue the foam cubes together to create a 1m x 1m x 4m block ...
Interesting Engineering on MSN

We forgot how to make concrete

Concrete has become so intrinsic in our everyday lives that it feels impossible to imagine a world without it. And yet, the recipe itself was almost lost to time. What secrets lie behind this crucial ...