Steam Source for a Wood-Bending Setup

Woodworkers discuss the steam supply for a shop-built wood-bending rig. March 28, 2015

Question
I am planning on building a box with a wallpaper steamer to do some bends on smaller pieces. I would like to know how big of a unit I can make using a wallpaper steamer. Any advice would be appreciated.

Forum Responses
(Architectural Woodworking Forum)
From contributor Y:
I made a small 4/4 pine box 5 ½x4x24 and used the steam bending kit from Rockler. I’ve had much larger boxes but the steam source was a five gallon can.



From the original questioner:
Do you think the box could be bigger and still effective? I just want to know how big I can go before I need to go to a bigger system.


From Contributor H:
Years ago I tried the wall paper steamer trick. It isn't going to give enough steam for a very large box - perhaps 12"x12"x24" at the most I would think. Even that might be pushing it. These machines pump out very little volume.


From the original questioner:
Is there a safe way to put a bigger one in my shop? I have seen the ones that run off propane tanks but I was told they are not safe for inside of a shop.


From Contributor H:
I use a steam bath steam generator. I picked it up inexpensively as excess inventory from a dealer years ago. It is electric and I think runs on a 20a 240v circuit. It does well on a 10" x 10" x 8' long insulated box. When we extend that box to 12' it begins to press the limits of the steam generator. For a box we purchase 4x8 sheets of 1 1/2" or 2" thick foil faced polyisocyanurate. That is available at most building supply stores. Rip it to width and the table saw and then press in 16d galv. box nails with your fingers to hold the box together. A few dowels pressed in every 2' or so down the length act as a support shelf for the wood.


From the original questioner:
I would like to build something that I can put about a 7' long board in. Do you think a wallpaper steamer would work, or possibly two wallpaper steamers?


From contributor U:
You are making this too complicated. A propane camp stove and a five gallon bucket will make all the steam your seven foot board needs. Or a "crab cooker" if you think you need more. Some galvanized tin house ducting, a "T" fitting in the middle and a cap for the end and tin foil will work. Elevate your board so that it doesn't sit on the bottom and steam/heat can flow all around. Steam bending has been around long before there were wall paper steamers.


From contributor U:
Don't forget that when you remove the steamed part from the box, time is of the essence. You need to get it bent before it starts to cool. Have this figured out in advance.


From the original questioner:
I want to avoid open flames in the shop that's why I am trying to find something electric.


From contributor U:
Around here the steam part is done outdoors. Most fishermen don't have a shop to do it in anyway. In your case an electric hot plate would work.


From Contributor W:
I've had issues when I've used anything containing iron in the steam chamber. I prefer stainless steel to plated/coated.