Replies

1. 
   saschafer | Jan 18, 2008 06:39am | #1

   Well, I don't think you can realistically generate enough steam for bending without boiling water. As for safety, I think your best bet is an electric teakettle. Here's a photo of one that Lee Valley used to sell (it doesn't look like they do any more):

   View Image

   Everything is enclosed, so the risk of scalding is pretty minimal.

   Lee Valley also publishes a good primer on steambending, which you can find here.

   -Steve

    

   
   

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   Edited 1/17/2008 10:46 pm ET by saschafer

2. 
   hammer1 | Jan 18, 2008 08:02am | #2

   How big are the pieces you are going to work with? I don't think any manufacturer makes a steam box for woodworking. We make our own to suit the project. A small box could be made with a wallpaper steamer. You can rent them and they would be enclosed. One problem is that you need to generate thick, billowy, continuous steam, often for extended periods. Small kettles can run out of water before the job is done and most shut themselves off when they hit the boiling point. A wallpaper steamer won't fill a large box sufficiently. You also have to realize how badly steam can burn someone. Full protective gear in addition to a number of safety training lessons would be in order. The work only remains pliable for seconds. You need to move fast and efficiently. It's when you open the door and grab the work that you are at most risk of hand and face burns.

   Not knowing what you want to make, there may be other options to bending. Using green riven stock is one possibility. Laminating with thin strips is another. There is kerfing and bending plywood is available.

   Beat it to fit / Paint it to match

3. 
   RickL | Jan 18, 2008 05:07pm | #3

   Without boiling water it won't be hot enough. Guitar makers use a hot pipe to shape the sides but typically it's heated with a propane torch. The more expensive ones have an electrical heating element. Wall paper steamers are expensive so you could go with a hot plate and 5 gallon gan and heavy duty hose. Steam boxes can be made of marine plywood or even heavy PVC with endcaps.

   If you want  hazard proof bending go with laminate strip  bending or http://www.bendywood.com

4. 
   doorboy | Jan 18, 2008 06:28pm | #4

   Jiffy Steamer--you should be able to rent one.
   Build your box big enough for your project pieces, but not so big that there is a lot of wasted space in there. Steam the work for approximately 1 hour per 1" of thickness.
   Remember that some woods don't take well to bending.
   Good luck.

   "She wrote a long letter, on a short piece of paper." Traveling Wilburys
5. 
   oldbeachbum | Jan 18, 2008 09:58pm | #5

   You might check the New Yankee Workshop site.  I believe Norm did something with PVC pipe a couple years back.  He was using a propane setup similar to what you might use to have a backyard clambake or a turkey fryer. 

   As everyone cautions....steam and it's heat source are always potentials for injuries.  Steam under presssure........ dangerous.

    

   Good luck

    

    

   Not to give you a hard time and I'm sure you have heard this before, there is an irony of your name and your job (description).

   ...The unspoken word is capital. We can invest it or we can squander it.  -Mark Twain...Be kind to your children....they will choose your nursing home....aim low boys, they're ridin' shetland ponies !!

6. 
   terrylee86 | Jan 19, 2008 06:15pm | #6

   Bob,

   Being a science teacher for over 35 years I understand your concern for lab safety and not cobbling something together that will work, but the administration would never defend you using. I have used a wallpaper steamer for my steam source. These are commercial units that heat the water electrically. You may be able to rent one for a single application. All you have to do is remove the hand plate that you hold against the wallpaper and hook the hose up to your steam box. One hour per inch is a pretty good rule of thumb. Make sure you use a backing strap when bending a tight radius. I usually made mine out of spring steel banding material I got from the local lumberyard. They will usually give you all you want because they hate handling the stuff. Screw end stops on one end and a handle end stop combo on the other. When it comes out of the box, set the hot board in you strap rig, clamp the one end and grab the handle(it is not hot) and bend it around your form. Then clamp all along the form. Make sure you allow for spring back when making your form, because it will always spring back, a lot or a little depending on the species. Another point always try to use quatersawn material. Flatsawn will work but watch for grain run out, because it will always split there. Sorry if I gave too much info, but I felt like one teacher talking to another.

   Terry

7. 
   TonyCz | Jan 20, 2008 08:08am | #7

   I am in Redondo Beach and if you like, you can check out the steam box I built and use.

   The burner and water tank.

   The burner is a propane burner like what is used for cooking a turkey with oil. aval at the HD, Lowes etc.

   The water tank is an old red 5 gallon solvent can filled with about 4.5 Gallons. ( 4.5 gallons will only last about 2 hours) 

   I used Marine exaust rubber tubing 1 3/4" or 2" from the rubber tubing to fit the ID of the can's neck.  I then made up a copper sleave from water pipe which would fit into the exaust tubing and reduced it down to 1/2" using a 90 to help line up the hose better to the box. In so doing I could set 5/8 ID rubber garden hose over the 1/2" copper pipe which would feed to the steam box. The steam box I made is 8'6" long and roughly 12"x12" made out of pine pained inside and out. Inside of the box is blocks of wood set at and angle chevron style so when the box is being used, I tilt it up to the excess water will run out.  It is also used to support the wood to be steamed so the steam can surround the wood.  If additional wood is needed to be steamed you can also place dowels inside the box by drilling holes on each side of the box and insert the dowels for the needed support. Red oak is a great wood to show how the steam can soften the wood so it can be shaped to a form.

   I should have used plywood,  but it works with the pine.

   I have doors on each end for venting as well as loading the steam box.  To emit the steam evenly inside the steam box, a copper 1/2" pipe is running the length of the box with a cap solder at each end and there are 1/8" holes drilled into the copper at about 4" spacings. In the center there is a tee which runs out the bottom where the rubber hose connects from the steam tank. 20 Minutes to make steam at 210 deg. Remember any steam you produce will be burning hot no matter how you make it. always use leather gloves and safety glasses.

   This I know may be over the top for your needs but this is my method.  

   I hope this method is a help.  

   Tony Czuleger

       

1. 
   Woodman41 | Jan 21, 2008 12:19am | #8

   Tony,
   Woodteacher's question was pretty straightforward, he needs a source for a steam machine that doesn't expose students to boiling water or open flame risk.

8. 
   ted | Jan 21, 2008 12:53am | #9

   Get the kettle pictured in a previous post. You can buy it from Lee valley. While you are at it get a book on bending either by Michael Fortune or Lon Schleining.
   The kettle shown will supply enough steam to heat a box 6" x 6" x 24" long. It will heat material upto 1/2" thick before running out of steam.

   
   

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   Edited 1/21/2008 9:30 am ET by ted

1. 
   Woodteacher | Jan 21, 2008 11:34pm | #10

   Thanks Ted

   Bob

9. 
   EdHarrow | Jan 30, 2008 06:06am | #11

   I've been working on a project at a boatwright shop - I queeried them about this odd looking contraption, it had a vertical rod, maybe a bit over three-feet high, a short length of flexible rubber hose, maybe 1.5" dia, something like that, mounted to a plastic base about 1'x.75'.  "Oh, that, that's a garment steamer, we use it for small bending jobs."  Looks like it comes really close to what you want.

1. 
   Woodteacher | Jan 30, 2008 08:39am | #12

   Thanks very much ED.

    I also have found the same thing and I am looking to it.

   Thanks again

   Bob

10. 
    ASK | Jan 30, 2008 04:39pm | #13

    For my first successful attempt at steambending I rented a wallpaper steamer.

    Subsequently I purchased the steam kettle from Lee Valley. I like the wallpaper steamer better.

    I actually purchased 2 Wagner wallpaper steamers for their intended use for about $50 each but have not used them for steam bending but I suspect that they will work just fine.

    ASK