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I am designing a home theater that will have a small "stage" which will need to have a long (~8ft long, ~6in wide, thickness as required) piece of wood that is bowed slightly. I want to know what types of wood (e.g. MDF, certain plywoods, ect...) would be suitable for this task as I need to be able to bend the wood to shape.

This image is how i'm hoping it will look. enter image description here

Note: the "stage" platform will be carpeted over so finishing the wood is not necessary.

  • Do you have a drawing or picture? You say the piece is 8ft long, but how wide and how thick does it need to be? – grfrazee Jan 12 '16 at 19:12
  • @grfrazee I would say it should be around 6" wide at most. I'm honestly not sure about thickness. I guess the type of wood will help determine that. – Programmer Jan 12 '16 at 19:18
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I am designing a home theater that will have a small "stage" which will need to have a long (~8ft) piece of wood that is bowed slightly. I want to know what types of wood (e.g. MDF, certain plywoods, ect...) would be suitable for this task as I need to be able to bend the wood to shape.

I would say it should be around 6" wide at most.

I think MDF or a good-quality plywood would be perfect for this application.

To get the curve, you would cut a series of parallel kerfs in one side of the board, similar to the image below.

kerfs
(source)

The spacing of the kerfs isn't an exact science, more of a trial and error thing.

As you can see, you only cut part way through the board. Ideally, if you use plywood, the ply you have left uncut has grain running perpendicular to your kerfs so that you're not bending across the grain.

I'm honestly not sure about thickness.

I would say your fascia board can be 3/4" thick and be fine. You would want to put another supporting board behind the fascia and under the stage pretty closely anyway to help carry the stage load.


Otherwise, if you want to get really complicated, you could use a solid hardwood and steam bend it the old fashioned way. Hickory, ash, and oak take bending well. See this related forum post for other woods. Air-dried lumber tends to bend better than kiln-dried, FYI.

For as light of a bend as it seems you're looking for, you might just be able to use several thinner boards (say 1/4" thick) and laminate them into the curve by gluing them into shape. It's fairly easy to make a jig to do this:

laminates
(source)

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    Oh man, that's an excellent answer. I was wondering how I was going to bend the wood and that is a great idea! Do you think a section of plywood that long will be ok to bend without the cuts? – Programmer Jan 12 '16 at 19:28
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    @Hooplehead24, "try it and see" is the best advise I can give you, unfortunately. 1/4" plywood will probably be fine. Not so sure about 3/4". – grfrazee Jan 12 '16 at 19:43
  • Just out of curiosity why does the thickness of the plywood matter? For that matter why would you want to use anything but a single board as thick as one of the plywood layers? What's the purpose of keeping the rest of the plywood layers behind the front bent layer after slicing them up? Like, in that image, if you removed the little remaining 4-layer sections, what would the difference be? – Jason C Jan 12 '16 at 20:36
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    @JasonC, thinner plywood is easier to bend, which is why that kerfing technique works. You want to keep the "behind" layers there because they add strength to the sheet. Otherwise, you'd just have a ~1/8" thick ply, which would buckle very easily if you loaded it on-edge. – grfrazee Jan 12 '16 at 21:17
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There is a type of plywood called bending plywood. All (or at least many) of the plys are parallel in grain not cross grained. It's pretty floppy. Glue several pieces to build up your arch. It's available from better lumber yards.

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