Wall Lamp Construction Question

[Dave Richards]

I saw a wall sconce in a restaurant this morning that I like. It was made of metal but I was wondering about doing it in wood. I did a quick SU drawing to illustrate what I remember seeing. Ignore the wall plate. The part I'm wondering about is the curved channel. I was thinking that I could laminate it up around a form and then use a router to cut the groove. I haven't quite worked out how to create the angled sides in the channel but I have a coulpe of ideas.

So my question is, what do you think of the idea of doing that channel in wood?

[Jamie Buxton]

Yeah, you could laminate the curve, and then hog out the middle with a rabbet bit guided by a ball bearing. The curve will change when you hog out the middle, so you may need to make a couple, experimenting until you get the design radius. You'll also need to think of some way to sand inside that U-channel; the router bit won't leave a perfect surface.

A slightly different approach would be to avoid the bent-lamination thing. You've probably gone to lamination because if you bandsaw nearly 180 degrees of a circle from one piece of wood, it will have short-grain areas. However, you really stress the circle only in the section between the mount to the wall and the mount to the hanging lamp. If you arrange the grain so that that section is not short-grain, you'll be stronger. You can also move the wall-mount intersection higher, to shorten the high-stress section.

Another help would be to make most of the C solid, not U-channel. You can carve just the visible ends to that u shape, preserving the strength elsewhere. Also, by allowing yourself a solid cross-section elsewhere, you can make the C from, say, three (unbent) pieces of wood. There's enough meat in the solid cross-section that you could do some sort of joinery -- for instance a bridle -- between the pieces.

[Matt Meiser]

What about doing a bent lamination, but like Jamie said, only make the visible parts channel shaped for strength?

[Jamie Buxton]

Here's what I was trying to describe in words. There's two views: the front and the back. The front looks like your drawing. The grain direction doesn't come through the web manipulations very well, but it is arranged to avoid excessive short-grain near the bridle joint.

[Dave Richards]

Thanks for the suggestions. I hadn't thought about limiting the length of the channel. I was concerned with running the wire down to the wall plate but I suppose I could use low voltage and run two individual conductors in very thin, shallow slots.

hmmm.


Thanks again guys.

Dave

[Frank Chaffee]

Dave,
I don’t see the utility, practically or aesthetically, in duplicating a steel channel shape. Since you are already considering doing the curved member in a bent lamination, how about constructing a rectangular tube in wood? The ends could be capped with either the same wood or one that contrasts in color, and the wire could still be concealed in the hollow.

Just a thot…
Frank

[Doug Shepard]

Is it just me that's thinking the overall shape of this setup looks like ...
http://www.angelfire.com/pa/lkmarvin...es/surnder.jpg
?

[Dave Richards]

Frank, as I said in my first post, I was just going by something I saw and liked. While looking at it I wondered about making it in wood. I kind of like the channel look anyway.

So how would you make this hollow box shape anyway?

Doug, you know I was thinking that shap seemed kind of familiar. Maybe I should add the bristles along the top of the channel?

[Frank Chaffee]

Dave,
I like the steel channel shape too, and have worked with it extensively including rolling it flange out as in the lamp you saw and like. Maybe my familiarity with it makes me feel uncomfortable seeing it imitated in wood, even though it’s structural integrity does translate.

As to how to make a hollow tube by laminating strips of wood how about this…?
• Cut one or more thin strips of wood that are the width of desired tube, for both the inner and outer radii of the tube.
• Cut two or more thin and narrower strips for each of the side walls of the tube.
• While assembling, gluing and clamping in a curved form, use either open or closed cell weather stripping foam to maintain spacing between the side wall strips.
• Remove foam before glue sets up.

Disclaimer: I have often had to come up with a plan B, so take this w/ a grain or two of salt.

Frank

[Jim Becker]

As an alternative, do it in metal, but veneer it...however, the challenge to do it in wood sounds interesting. I also like that design, BTW. Definitely low voltage, too.