1. ## Fibonacci Gauge

As some joker said, not a lie detector for Italians.
Very worthwhile for all wood workers/turners. I'm going to try to make one.

2. Very interesting device. Looks like a pretty simple tool to make, and worth the effort. I've got scrap strips cut out of 3/4" hardwoods in either 1/2" or 1/16" thicknesses. (Cutting board leftovers.) I've even got some flat portfolio screws that should work for the pivot points. Looks like pretty simple geometry to figure out the rest. Once you had the three points laid out, the rest could pretty much be done by eye. (That's my kind of woodworking...measuring is so overrated.)

3. Plans were posted on a pen forum. I captured the picture below.

4. Member
Join Date
Nov 2006
Posts
896
Neat device Frank. I wonder if there are digital equivalents for CAD programs?

Wes

5. Member
Join Date
Dec 2006
Posts
370

## Neat Gauge

That is a slick gauge, but you weren't told why it was named Fibonacci gauge.

Leonardo Fibonacci was an Italian mathematician born in 1175 AD. In a book he published in the early 13th century, he defined the Fibonacci number sequence. The sequence is formed by adding together the previous two numbers in the sequence to obtain the next number. 0 1 1 2 3 5 8 13 21 34 55 89 144 etc.

How does the relate to the Greek 'golden ratio'? As it turns out, if you take any number in the Fibonacci sequence and divide it by the number previous to it, you will get an approximation of the 'golden ratio'. The larger the selected number the closer the division comes to the 'golden ratio'.

In the above sequence, if you divide 3 by 2, you get 1.5, but if you divide 21 by 13 you get 1.615. Going further up the sequence, 144/89 = 1.6179. Since the sequence is infinite, we can assume that the golden ratio is also infinitely long. As it turns out, the golden ratio is defined as (1+ sqrt(5))/2. The sqrt of 5 is a number that is also infinitely long, hence the golden ratio is also infinitely long.

Things like this lead one to think that the Great Architect of the Universe is a mathematician.
Last edited by Ken Garlock; 04-06-2007 at 04:16 PM.

6. Originally Posted by Ken Garlock
That is a slick gauge, but you weren't told why it was named Fibonacci gauge.

Leonardo Fibonacci was an Italian mathematician born in 1175 AD. In a book he published in the early 13th century, he defined the Fibonacci number sequence. The sequence is formed by adding together the previous two numbers in the sequence to obtain the next number. 0 1 1 2 3 5 8 13 21 34 55 89 144 etc.

How does the relate to the Greek 'golden ratio'? As it turns out, if you take any number in the Fibonacci sequence and divide it by the number previous to it, you will get an approximation of the 'golden ratio'. The larger the selected number the closer the division comes to the 'golden ratio'.

In the above sequence, if you divide 3 by 2, you get 1.5, but if you divide 21 by 13 you get 1.615. Going further up the sequence, 144/89 = 1.6179. Since the sequence is infinite, we can assume that the golden ratio is also infinitely long. As it turns out, the golden ratio is defined as (1+ sqrt(5))/2. The sqrt of 5 is a number that is also infinitely long, hence the golden ratio is also infinitely long.

Things like this lead to think that the Great Architect of the Universe is a mathematician.
There are some things in life we just don't need to know.
He was ITALIAN, that's all that is important.

7. Member
Join Date
Oct 2006
Location
Forest Grove, Oregon USA
Posts
290
This is one which a friend made for me.

They do work well to check out proportions quickly, layout spaces say for drawers/doors.

Take care, Mike

8. Mike, that's a beautiful tool. I'm kinda envious. The tips look like they could be ivory.

9. Member
Join Date
Oct 2006
Location
Forest Grove, Oregon USA
Posts
290
Hi Frank--nope, they are brass. I just did a losy job of taking a picture. Too much light. In fact, the wood is nicely figured, a detail which is also lost in my picture.

Shows the brass color a bit better--but still not the wood's figure. One day if I find the energy perhaps I'll take another picture...

Take care, Mike

10. Don't bother. I'm even jealouser now.
Beautiful.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•