How to machine radius on long surface of board

[Christopher Giles]

Do you know anyone with a W & H planer? This is right up their alley. A set of profile knives used to be $100.00, not sure if that is still the case. With this set-up, you could run these six parts in short order. Maybe someone on this site can help out?

[Prashun Patel]

Does this need to be an accurate radius (like a circle) or is it ok if it's just a matched crown somewhere in between a caternary curve and a true arc?

If the latter, it's surprisingly easy to do this on the table saw. You'd make a starting bevel cut, flipping edge-for-edge on each piece. Then you make the angle slightly less acute, move the fence in a tad, and make another 12 passes on your stock. You can calculate the bevel angles, eyeball them with a protractor, or just do like i do: guess.

You would only need to do this about two or three times.

The sanding will remove all evidence of the facets. I've made more drastic radiused curves like this and am always amazed how accurate and easy it is - especially since you only have 6 six-foot pieces to do, they're tall enough but not too tall to be done safely on the tsaw, and it's walnut which sands easily.

My eyes say the important (and easy) thing is getting the symmetry right, not the actual accuracy of the curve.

If you're comfortable with a hand plane, you could even easily hit the bevel corner transitions with a hand plane before sanding.

[mreza Salav]

Build a box to resemble a long lathe, attach the boards to using a support behind (cross-section will be a T) and use a router to form the curve.
I've used the method to create posts or half circles successfully. You don't need to build the box big enough to accommodate a full 360 degree turn. Just turn the board left and right enough until the full width of it passes the router cutter. It can be a shallow box. The T support idea is to prevent the board from flexing. I used a small length of 3/4" pipe and flange screwed to the ends to make the "shaft". You can screw two small round sections to the two ends of the board and attach the shaft.

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[Chris Fournier]

Once upon a time I made two sleigh beds, a queen and a king. The foot and head rolls presented similar challenges to yours in cherry and soft figured maple. I had a profile template for the two rolls and I cut bevels on my TS very close to the profile scribed on the roll ends. I then used a hand plane to facet the pieces even closer to the profile. Once I was on the pencil line with the hand plane I took 6" wide sandpaper from my edge sander and cut 24" strips and fixed wooden handles on each end of the paper strips. I put the rolls on saw horses at each end and then use the sandpaper across the profile to fair it to perfection - think of a sawing motion perpendicular to the grain. After the profile was sweet, I sanded from end to end to finish using shorter strips with handles. Easy to do, no additional expense, and the process stayed in my shop where I could make sure that I got exactly what I was after. All in all it was not a monumental task but it was very gratifying!

[Mel Fulks]

Torus mould. You can do this . I think the question is can you enjoy or endure all that whittling. A drawknife might help.

[Mike Wilkins]

Remove as much as safely possible on the tables with the blade tilted, then go at it with some hand planes and sanders. First make a template of the desired shape to check your progress as you go.