I've been refining the design I put up in Part 12 with the idea of making a prototype. I like the general motion and pattern but I find the "flash" when the outside forms overlay each other distracting. I tried several different methods to get around this and finally found a very simple solution. I simply made the outside rings on the front wheel slightly larger than those on the back wheel. Now, rather than flashing, the two forms seem to flow into each other. I also gave the outer rings a little more form by thickening the center parts of each ring part.