How did they do it?

[Paul Ray Moore]

A friend asked if I could turn a replacement stretcher for a chair. This is the one she gave me for a sample.
When I got it I realized it was octagonal.
Anyone have an idea how they did this?
The friend said they would be ok with a round one if I couldn't do the octagonal shape but I wondered if I could do something like this on a lathe.
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[Roger Chandler]

Turn the same spindle oversize with the exception of the coves, measure each cove with a caliper and get them down to the same diameter. Then secure it to a bench and take a belt sander and sand/turn the flats........keep checking on the size of the spindle frequently with this one laid by its side, to make sure you do not take too much off. I would lay out the vertical lines first, then sand down to nearly even with them, then refine it by hand. This might take a while, but you should get a match.

Another plan might be to use a block plane to get them down to near the lines.......either sander or plane could be used, but the plane might catch on the edges of the coves and misshape them. Good luck!

[John K Jordan]

I saw some made with a router following a template.

[Hayes Rutherford]

Mount stock between centers. Place pattern on top, follow with a router using appropriate bit. Rotate 45 deg. Repeat.

[Hayes Rutherford]

John, I was responding at the same time.

[Robert Henrickson]

I suspect it was thermed -- many spindles turned simultaneously on a drum.

[Marvin Hasenak]

Search "How to make octagon handles". You will need to make an indexing jig so you can duplicate the octagon shaped parts. The jig will also need guides so you can cut the curves in the octagon part. After that I have no clue, I made some octagon handles but they were a simple curve. This might give you an idea. http://www.cornishworkshop.co.uk/chiselhandles.html

[Dick Strauss]

If the bevels are flat, it wasn't done on a lathe with the piece spinning but rather done with a routing device (CNC or other) and indexing with a template.

If the bevels aren't flat, they were turned (or possibly CNC milled) by loading up dozens of spindles sandwiched around the perimeter and between two plates at the headstock and tailstock sides with holes drilled to capture all of the spindles (kind of like two seats on a windsor chair with equally spaced holes drilled all the way around to make a birdcage like structure). You then have an interrupted cut where you turn one side of dozens of spindles at a time. Once you are done, you index/rotate all of the spindles to the next side and continue working your way around until all sides are done.

I will be a tough and time consuming task either way. Good luck!

[Geoff Whaling]

I suspect it was thermed -- many spindles turned simultaneously on a drum.

Therming is possible for production but not viable for a "one off" repair. In this instance when one looks closely at the coves and flat not slightly curved faces of the elements it appears to have been made with a router & template with an indexing jig.