I needed a steam box to steam bend a walnut handle. The last time I, steam bent a handle I just threw it in a contractor bag and pumped it full of steam. This worked OK but by the end of the steaming process the bag had started to melt and it turned into a bit of a mess.
This time I decided to build a proper steam box, but lost interest because I hate shop projects, I’d rather be building furniture. Instead, I built a down and dirty steam box.
To build the project I used four, 6-foot cedar fence boards and cut them down to about 5 feet so I would have a few scraps long enough to cap the ends of the steam chamber.
One end was fixed and nailed into place the other end was hinged. The next time I use this I will probably put the hinge on the bottom so when I open it and the steam boils out it can go straight up without burning my hand.
I didn’t have any dowel stock to build the rack inside of the steam chamber. Instead, I used some of the scrap from the ends and cut them into 3/8” square stock. I then used a hollow mortise chisel to cut mortises for the square pegs to sit in.
When I cut the mortises, I clamped the two boards together to ensure they would line up perfectly. I also cut the mortises on a diagonal so the square pegs would sit on an angle in the box. In theory, this would prevent stock form getting stuck on a square edge when loading the box. The porous of creating a rack on the bottom of the steam chamber is allow steam to circulate all around the piece, and prevent it from just lying in a puddle of water on the bottom of the box.
To keep a steady flow of steam in the box re-purposed one of those fabric steamers to steam out wrinkles. They don’t really work well for that but they worked great for keeping a steady flow of steam in the box. Chair maker Peter Galbert has good luck with wallpaper steamers
I did learn a few things about hose placement in the box. It needs to all be on the top. In the video I have it placed on the bottom. The problem I kept running into was the condensation kept draining back into the hose and filling it with water preventing more steam form flowing by. Before I use it next time I will plug the hole in the bottom and reattached it to the top which will allow me to keep the steamer and hose all on top letting the condensation drain into the box and out a drain hole.