Post #3 - Tetrahedral

Vessel (2010)

I began slab building vessels in earnest in 2010, though I had a short flirtation in 2004. For someone like me, with some experience working with wood and metals, the ins and outs of the process was very easy to assimilate and it wasn't long before I was making substantial items like the object above.

It wasn't all plain sailing. I assembled a tall, two sided vessel, made by curving long slabs around a large cardboard tube, such that in plan view it  had an ovoid shape, with a simple slab section joining the base. Like the object in the headline photo, I was looking for more expressive ways of presenting the opening, not just a simple hole. So I made the neck of this two sided thing curved, asymmetrically. It looked fine from front/side, but edge on, though, it made a deep V shape. This shape would literally be the undoing of this vessel. The bisque fire presented no problems, though I seem to remember there was a crack. I carried on and glazed it. Mistakes happen, and I learnt from this one. My tall, reasonably elegant looking vase had split right open along the joint. Having studied engineering in my distant past, I knew it was because I had inadvertently made a stress point. Corners on any object are areas of maximum stress (that's why the tips of things break off more easily) and for an open V shape, even more so. So when the clay shrank during firing, the internal forces arising from the shrinkage pulled the joint open like a zip.

Some years ago I did some concept sketches, annoyingly undated but drawn sometime in 2004. Even then I was calling them 'Tetrahedral Forms' :

So far I haven't got anywhere near the more curved shapes I envisioned. In practice leather hard clay slabs are quite difficult to shape. I tried again with the vessel below:

Another Vessel (2011)

Curvature is relatively easy to achieve on a plane, but what I am after is a bulge on each of the faces. I think this will require a specific object (like a huge wooden belly for instance), such that I can allow fresh slabs to reach the leather hard state in a shape much nearer to what I want.

Another slab-build sculpture - much more free form than these - that I started building shortly after my first tetrahedral will be a follow on from this, as it deserves a post of it own.

Next post - Horse.

~J~