Best way to build/shape this?

Rennie Heuer

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Though I am in the middle of my 13 flag cases I am already working on the design for my next project - a curved side Arts & Crafts mantle clock. I'm planning on building at least two, one in mahogany and one in QSWO - maybe one in walnut also - and I am trying to figure out the best way to form the curved sides. I am taking styling cues from several other clocks I like so's not to strictly copy anyone else's design A little math first, then I can review some ideas I came up with.

The clock will stand about 16" tall, 9 3/4" wide and 5 1/2" deep. The face of the legs is 2" wide at the bottom and 1" wide at the top. The inside of the leg is perpendicular to the top/bottom, only the outside curves. The sides are 1/2" thick at the top and bottom, 3/4" thick near the center - I say near because I have not yet decided on the shape of the arc.

Curved Side Mantle Clock A.jpgCurved Side Mantle Clock B.jpg

Since I am building multiples, and may have cause to build another someday, I may build a jig for the router table to shape the legs - maybe - as two of my solutions below would not require a jig for shaping the legs.. Now, the challenge of shaping the sides.

For the most part, getting close to the final shape using the bandsaw seems the best course of action should I decide on a single solid piece. The shaping afterward is what I am giving some thought to.
  1. I can build a second jig and using a large flush trim bit I can shape it in two passes, one from each side. The issue I see here is that there is a lot of exposed bit so I need a stout jig that both keeps my hands far away and holds the work VERY securely. Also, I will be routing across face grain - seems like an invitation for tear out.
  2. Same as #1, but attach the side between the legs before routing and use the edge of the leg as the guide for the bit. Same issues as #1.
  3. I can band saw the sides and use my 4" stationary belt sander to rough it down then use a scraper and finer grits to bring it to final shape. lots of work and dust, but avoids tear out issues. I don't have one of those fancy planes that can be adjusted for curves. Also, in not using a jig I may introduce small variations in the overall shape of the leg/side assembly. Don't know how noticeable that might be, but since I am planning to sell these near the $500 mark I want them to look perfect.
  4. Same as #3, but mount the rough shapes legs to the sides and bandsaw all at same time. Advantage here is no fussy glue up trying to align curved surfaces.
  5. Use a secondary wood to form the sides and veneer the primary wood to it. The advantage I see here is (especially with the QSWO) I won't be exposing little bits of end grain across the curved face. Don't know if that is really and issue, just being cautious.

I am leaning towards solution #4 providing there are now grain issues curving across the face.

Thoughts?
 
Glenn B with his G&G experience probably has some better ideas..

For a one off I'd rough cut on the bandsaw, get ~most~ of the shape done with a hand plane then fair it with sandpaper (possibly use a curved MDF backer with the paper stuck to that depending on how accurate I was feeling the need to be). I don't think the amount of exposed end grain would be super noticeable with that small of a curve but could well be proven wrong upon trying it.

Another option would be to do the whole thing as a laminated piece built up from strips. That would be the most repeatable once you have the form made and ready. You could use a secondary wood for the backing strips.

You might also look at the "flexible plywood" or "radius bending plywood" products. They aren't super expensive and give you a nice substrate to use for veneer work although for a small number of high end builds I'd likely just use shop cut oak for consistency of material (assuming you have a drum sander for fine thicknessing .. otherwise its a bit much to do).
https://www.columbiaforestproducts.com/product/columbia-radius-bending-plywood/
https://www.andersonplywood.com/410/bending-boards-shape-forming-panels/
http://www.winwood-products.com/eng/timber-products/plywood/flexible-plywood.htm
 
I had some down time waiting for some glue to dry so I grabbed a bit of QSWO scrap and cut my curve on the band saw - a little steeper than the plan because I wanted to see how the face grain played out. Then I refined it on the belt sander befor hitting it with some 150in the ROS. Didn’t quite get all the bandsaw marks out, but ok for the purpose of this test. Added a little BLO to highlight everything and it seems to have come out OK. I’ll have to wait for it to dry and look at it under a magnifying glass and give it a touch test to be sure.
f52e75e361e92105d16c3421a869650a.jpg

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I'm with Jim. That is a great use of the bandsaw and an edge sander. I actually scale some pieces to be sure that I can sand portions on my 6" edge sander.
 
Consider insetting the sides from the edges of the legs. You can route a slot following the curved leg edge. Make the panel thin enough so it is bendable and it will form to the curved slot. Could be veneered plywood .. then wood movement issues are not a factor. Just another thought. Looking forward to seeing the progress.
 
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