A steam box is most commonly used to steam wood so it becomes more pliable. Originally steam boxes were designed to use for boat applications, making the large boat timbers easier to bend. You can probably find many uses for a steam box for yourself, and here’s how you can build one.
Build a Box
You will need quite a bit of space to build your steam box. You need to construct a wooden box that is seven feet long, one foot wide, and one foot high. You can just use cheap plywood for a steam box. This size will allow you to steam almost any plank of wood and still give you the room you need to place the square footing (we’ll get in to that later) in the box.
You want to get a piece of copper pipe that is long enough to fit the length of the box. You will want to drill holes in the pipe, like perforations, throughout the pipe to allow the steam to collect in the box.
Attach the Pipe
You need to drill a hole on the bottom of the box. Use a T junction in the middle of the copper pipe. This will exit through the hole. Be careful while drilling this because you need to ensure everything fits tightly. If it’s loose it will allow steam to escape and the box won’t function as well.
Attach PVC Hosing
Attach a flexible hose, preferably PVC, to the T junction. The other end of the hose should attach to the steamer. A wallpaper steamer or kettle will work well to provide the steam.
Use small squares of wood in the box to use as shoes. You don’t need many of these, usually four is enough. These will prevent the planks from laying on the bottom of the box to ensure even steaming. If the planks sit on the bottom of the box the steaming process won’t work, and you will have wood that is not completely pliable.
You can adjust the size of your box if you need to. A box that is too small can build steam too quickly and damage the box. In some cases the box can explode. A box that is too large won’t steam the wood properly and becomes useless.
As a general rule, you should keep wood in the box for one hour per inch of thickness. Steaming wood isn’t a fast process.
Always use gloves when you are working with steam. The steam can get hot very fast and cause burns unexpectedly.
A lot of people will place the steam box on a wooden workhorse for ease of use. If you prefer, you can build legs for the steam box easily. This is entirely up to you, and will depend greatly on how often you plan on using the box.