How to Draw a 13-Armed Fibonacci Spiral


It is impossible to draw a Fibonacci spiral, you can only draw a close approximation of one. As it is impossible to draw a 13-sided shape, you can only draw an approximation of one. So I set out this past week to draw a 13-armed Fibonnaci spiral. To do this I start with a 13-sided shape. Giuliana volunteered to draw the 13-sided shape and after several valiant attempts that came darn close, we got out the protractor. 360/13=27.69, and marked the degrees around the circle. I realized I wasn’t too clear in my last post about how I start the multi-armed spiral, so hopefully this post is better. In my web searches I also found I am not the only person confused on how to start the multi-armed spiral, and also that this is not the only way to do it. Maybe not even the best way to do it, but it’s how I do it. Here it goes:

I sure am learning a lot by doing this. It was a big revelation when I realized I could just draw a circle to guide the compass points. Right in the middle of each arm was the place to point the compass. I could make my way around the circle leap frogging over each arm into the exact center between the lines and place my compass point there. Of course this only works when you have done the first couple of revolutions, otherwise everything is just too small.