Four sided vessel help

[Ty King]

Can anyone help me with chucking options on a four sided vessel with convex sides simular to the one on the cover of the AAW Journal last month?

[Jim Burr]

If you use a glue block, mark four points on the back in the form of a square. Turn between the centers and just relocate to the marked points to create the offset. I think Michelle Rich did a tutorial on something similar earlier this year?