Steam Bending

Last but not least, you need heat.

If you were to try bending an unheated board, you would snap the board, or the boom, or both. Heat softens the bonds between the wood fibres in the board allowing adjacent fibres to slip past each other much as playing cards slide when you curve a deck of cards while shuffling them.

Boards are heated to this pliable state using steam. Here is the large steam box I used. A large propane torch heats a boiler which is periodically refilled with water. The hose at the end of the box drains water that has condensed in the box back into the boiler.

I heated the boards for the coffee table one at a time, each for about an hour. Using gloves, I trans-
fered the board into the bending strap, and then bent it around the form. This had to be done quickly, in less than a minute, because as a board cools the bonds between fibres form again. This is what allows a board to hold its shape after bending.