The bowl design was inspired by nothing more than an untidy stack of washers lying on the bench.
It looked a bit like a bowl and the concept of multicentred turning was quite fascinating.
I had to invent a method of holding the awkwardly shaped "bowl" firmly, while the various layers were being turned.
The "offset square" method worked quite well, once I mastered how it should be done, but this description relates to my third attempt!
First time round, I used centres which were much too far apart.
Second time appeared to work much better until I discovered that my external and internal surfaces for two of the washers were not concentric.
Getting the square corners right demanded rather careful use of a variety of skew chisels (and occasional use of the bowl gouge)
This project turned out to be quite difficult, for several reasons.
The choice of ash for the first prototype was quite wrong - it tears too easily. But walnut was fine.
I needed a plywood model to help me sort out the mathematics of the square mounting.
The required accuracy of the fixing points was also a challenge – "measure twice, drill once" is the motto.
And with so many blunt corners turning at high speed, safety had to be a constant consideration