Steam Bending Box

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I decided to run with Adan's idea about perhaps working on a steaming box, since that step will be coming up soon. I know some of us (like me)have plans for building a slightly larger boat, so 4' might not be long enough for a steam box. We had discussions before about perhaps building it in sections. I took a swing at that design. The best place to begin is with an image, so see the side view linked below.

https://knoxvillehackerspace.com/sites/default/files/photos/Side%20Image.jpg

The legs are short because it is designed to be a benchtop box. Making it taller requires a wider stance for stability. Attempting to conserve space with this one. It's designed to be broken apart in the middle and held together with a clamp like the one seen in the following link. The lid would be held on in the same manner, allowing the lid to be used for either the full or half length unit.

http://www.lowes.com/ProductDisplay?partNumber=311970-1277-890228&langId=-1&storeId=10151&productId=3355520&catalogId=10051&cmRelshp=rel&rel=nofollow&cId=PDIO1

The entire unit is pitched so condensate would drain. Sealing between the sections and/or lid could be accomplished with weather stripping and the hasp should provide the necessary clamping force.

The small circles on the side are for dowels to support the piece being steamed. It would heat unevenly and be more likely to warp if it were allowed to rest flat against the bottom. The exposed image shows the the interior structure (link below). It would allow the inclusion of a steam distribution system, though the pitch on the box would likely make that unnecessary. The hot steam will have a tendency to rise in the box, and then it will condense and run down to the bottom, allowing room for more steam to rise up. Phase change thermosiphons are very effective, and that's the main reason for the exaggerated tilt (5 degrees, total).

https://knoxvillehackerspace.com/sites/default/files/photos/Exposed%20Image.jpg

I'd like to give it a test without including any steam distribution system. I took a look at what it would take to make a distribution system that could be easily separated in the middle, and it seem much easier (and cheaper!) to just not have one at all.

Most designs I saw on the internet seemed to want to put a variable number of vent holes in the design that could be covered/uncovered to allow for a manual adjustment to balance pressure buildup with temperature loss. A much simpler idea that becomes possible with the tilted design is to install a condensate drain line with an S-trap. It allows you to easily eliminate live steam losses while making sure that you do not over-pressurize the box. Adding this type of drain will require that the unit not be used on the floor as designed because you'll need room under it for the trap and condensate bucket.