# Proportional Dividers - Golden Section and Generalized #1: Phi (Golden Ratio) Rule (Ruler, Scale, etc.)

 Blog entry by Mark Whitsitt posted 11-17-2010 08:00 AM 4402 reads 2 times favorited 7 comments
 no previous part Part 1 of Proportional Dividers - Golden Section and Generalized series Part 2: Proportional Divider (4 arms) - General Equation »

Hi,

I’ve been intrigued with the Golden Ratio (Golden Rectangle, Golden Section, Golden Mean etc.) for some time, and I’m getting ready to make a set of Golden Ratio (or Fibonacci) Dividers to assist in design and layout of some projects I’m thinking about.

I’m not going to review this topic in any great depth as there are excellent discussions of it right here on Lumberjocks (e.g. David's post). Suffice to say the Golden Ratio has many interesting features and appears to be significant in nature and aesthetics.

Specifically, the Golden Ratio is 1.618034, and is often given the generalized mathematical name “Phi”. One of the more interesting characteristics, to me anyway, is that the inverse of Phi is Phi-1. That is, 1/1.618034 = 0.618034
I think there is a mathematical categorization for such numbers, but I don’t know what it is.

Anyway, I found these “Phi rules” on Woodcraft earlier today, and thought I’d try my hand at generating my own template for such a rule. Here it is…

There are basic instructions in one of the PDF files. While the “English” scales are very close to being accurate, I DO NOT guarantee that 1 inch actually equals 1”. Even if the English measurements are off, the rule is internally consistent, so if you’re not into precision, you can still use this to lay out Golden Ratio dimensions.

Linked are a 24 inch Phi rule, which you’ll need a large format printer for; be sure to turn off scaling!

I also created a smaller 10 inch rule that you can print on standard letter size paper. This is the one with the instructions on it.

Enjoy!

Mark

-- -- "there are many good reasons to use old hand tools, but moral superiority is NOT one of them..."