The use of Golden number in wood turning.

[Claude Arragon]

The golden ratio, usually denoted ('phi'), expresses the relationship that the sum of two quantities is to the larger quantity as the larger is to the smaller. The golden ratio is the following algebraic irrational number with its numerical approximation


This number is still quite frequently used by architects, designers, artists to obtain closet o perfect proportions.
A friend of mine, Jacques Portal, Turned this bowl in strict observance of the golden ratio.




For diameters:
370 / 140 = 2.618 (square of 1.618)
From which you can deduct:
370 / (115 + 115) = 1.618
(115 + 115) / 140 = 1.618

For eighth:
75 / 46 = 1.618

We can add than the depth of the bowl is 370 dived by the square of the square of 1.618. But let’s not exaggerate, we can be satisfied to commonly utile 1.618, it’s square or it’s square root. We are not that fussy or anal compulsive. Are we?

[John Hart]

So....I visited this question a little while back....and tried to stay in the parameters of the ratio....looking for beauty in a mathmatical equation....and in the end, I had to ask...What was accomplished?

My answer to m'self was this.....

The golden ratio yields a turned piece that has a form. It can be beautiful or it can be clumsy...depending on where you apply the ratio. Also....and probably most important, is that a piece can be turned that is spectacularly beautiful and NOT have anything to do with the Golden Ratio.

So....is it real? Or is it a mathematical coincidence.....some of the time.

I enjoyed the question though.

[Keith Burns]

So....I visited this question a little while back....and tried to stay in the parameters of the ratio....looking for beauty in a mathmatical equation....and in the end, I had to ask...What was accomplished?

My answer to m'self was this.....

The golden ratio yields a turned piece that has a form. It can be beautiful or it can be clumsy...depending on where you apply the ratio. Also....and probably most important, is that a piece can be turned that is spectacularly beautiful and NOT have anything to do with the Golden Ratio.

So....is it real? Or is it a mathematical coincidence.....some of the time.

I enjoyed the question though.

You got it right John, Thanks.

[Malcolm Tibbetts]

Regardless of all the math involved, there is a fairly recently discovered reason that the “golden rectangle” (as opposed to golden ratio) is an effective design tool. It best conforms to the back of the average eyeball. It’s easy to look at. For anyone that would like to investigate this number more, here’s a very impressive site: http://www.goldennumber.net/

[Paul Downes]

I have heard about this ratio and have noticed that when objects have a certain symetry they tend to sell better. I turn turkey call strikers for a friend and we have noticed that certain shapes that seem to be 'balanced', and I suspect employ the golden rule in their shape, sell a lot quicker than shapes that seem akward in appearance. Makes you wonder about the hard wiring of the human mind.

[Martin Shupe]

I am not a turner, but I am interested in the Golden Ratio as it applies to cabinetry. I didn't know you could apply it to turnings.

I think, in this case, it works. Very nice bowl, very nice form, nice wood!

You have to develop an "eye" for what looks good. You can tell right off if something does not look good. If it takes a little math to make it look good, I am all for it.

Thanks for posting!

[Chris Barton]

While I do frequently apply the golden ratio to casework I rarely (not intentionally yet) use it when turning. In general, I have found that the "rule of thirds" has much greater application in turning.