Offset turning

[Royce Meritt]

At the most recent meeting of our woodturners club, some members were discussing a show they watched somewhere where the turner turned a 3-sided object and they couldn't recall how it was done. Am I correct in assuming it was done by mounting the stock on the lathe on 3 different off-set points 120 degrees from each other? See my crude sketch below! Am I correct that mounting the centers at point "A" would turn the side between point "B" & "C"; then remount at point "B" to turn the side between "A" & "C"; and finally remount again at point "C" to turn the side between "A" & "B"?

If I am all wet and this isn't how it would be done please set me straight. Thanks!

[Harvey M. Taylor]

Hi Ross,
yes, that is the way I understand it, but havent tried it yet.M. as in Harvey M. Taylor

[Mark Pruitt]

Royce,
Go to http://www.robert-sorby.co.uk/ and select Movie Clips. Then select Multi Sided Bowl Turning at the bottom of the list. It appears that you already have the gist, but the clip should prove at least somewhat helpful.
Mark

[John Timberlake]

If you want three side that are even and straight up and down the piece, that is the way to do it. You can also put them at something other than 120 degrees and end up with an asymmetric piece. I saw a program on www.thewoodworkingchannel.com (http://www.thewoodworkingchannel.com) where the demonstrator was turning a spiral. He put the centers at A on one end and B on the other, then B and C, then C and A. Created at three sided spiral on the piece.

[Andy Hoyt]

Young Ben Werner showed us all up with this effort (http://www.sawmillcreek.org/showthread.php?t=41053).

[Don Orr]

Royce, what you have shown is the basic layout for turning 3 sided pieces. You can do it on just one end, or on both ends. Point A should line up with Point A on each end, B with B, C with C. I did a demo called "Intro to Multi-Axis Turning" at Totally Turning 2006 in Albany, NY a few weeks ago which included this very subject. Cindy Drozda also did a 3-sided box as one of her demos at the same event. Accurate layout is important for symmetry if that is desired. Coarse grained woods like oak and ash tend to deflect the points of the head or tail centers, so fine grain wood works better. This technique is not limited to 3 sides. The same type of layout can be used for 4, 5, 6, sides pieces. There have been articles in several magazines about this as well. In my experience, spindle orientation of the wood works quite well, whereas bowl or face grain is much more troublesome.
There is a good book called "Multi Center Woodturning" (I think) by Ray Hopper. It's out of print but comes up occaisionally on the web auction sites.

Good luck and let us see what you come up with.