I know there is a easy way

[james mc guire]

I know there is a easy way to find the center and divide of a circle or tube without using alot of math,seems I saw something about using a framing square or something.anyone know of a way?I want to divide into sections but even i.e 8 sections of a pie with everyone getting equal pieces.

[Marty Tippin]

Try this
http://www.lsirish.com/tutorials/woodcarving-tutorials/woodcarving-fundamentals-techniques/working-with-your-patterns/dividing-a-circle-relief-wood-carving/
You can divide a circle into 4 or 8 parts with the method shown. All you need is a ruler and a compass.

[Prashun Patel]

To find a circle's center, draw a line between two random points on the circle. find the midpoint of that line. Draw a line perpendicular to that line through that midpoint to get a diameter.
Repeat. The two perpendicular lines will intersect at the circle's center. The other way to find the diameter is to I do it is to fix a ruler flush to one point on the circle and rotate it until it reads the maximum. If you repeat this 3-4 times, you'll get an accurate enough indication of the center.

If you want to inscribe an octagon inside the circle, set your compass or calipers or divider to ~.77 x the radius of the circle. Walk around the circle with that and you'll have the 8 bisection points. Connect opposing pairs and you'll have your pizza.

[Thom Sturgill]

the technique Marty linked to will give you any power of 2 equal parts - that is 2,4,8,16, etc. To get 6 equal parts, mark a spot on the circle and with the compass still set to the radius, walk the marks around the circumference.

[Dan Hintz]

To get 6 equal parts, mark a spot on the circle and with the compass still set to the radius, walk the marks around the circumference.

Not quite equal. The circumference is 2*pi*r, and since pi isn't exactly 3, you get some "leftover". A 1' circle split that way will have an extra 3.4" segment.

Just something to be aware of... if you're ballparking it, that's cool, but it won't be exact.

[Thom Sturgill]

Dan, that would be true IF the distances measured follow the circumference - they don't - you are measuring off chords. You get 6 equilateral triangles.

BTW the previous method will allow you to subdivide the 6 slices into 12, 24, etc...

[Bruce Pratt]

Just to go a bit over the top, it is possible, with compass and straightedge to exactly divide a circle into 2, 3 (http://en.wikipedia.org/wiki/Equilateral_triangle), 4 (http://en.wikipedia.org/wiki/Square), 5 (http://en.wikipedia.org/wiki/Pentagon), 6 (http://en.wikipedia.org/wiki/Hexagon), 8 (http://en.wikipedia.org/wiki/Octagon), 10 (http://en.wikipedia.org/wiki/Decagon), 12 (http://en.wikipedia.org/wiki/Dodecagon), 15 (http://en.wikipedia.org/wiki/Pentadecagon), 16 (http://en.wikipedia.org/wiki/Hexadecagon), 17 (http://en.wikipedia.org/wiki/Heptadecagon), 20 (http://en.wikipedia.org/wiki/Icosagon), ... parts (above 20 see here (http://oeis.org/A003401)). Conversely, it is not possible to exactly divide a circle into 7 (http://en.wikipedia.org/wiki/Heptagon), 9 (http://en.wikipedia.org/wiki/Nonagon), 11 (http://en.wikipedia.org/wiki/Hendecagon), 13 (http://en.wikipedia.org/wiki/Tridecagon), 14 (http://en.wikipedia.org/wiki/Tetradecagon), 18 (http://en.wikipedia.org/wiki/Octadecagon), 19 (http://en.wikipedia.org/wiki/Nonadecagon), ... parts (above 19 see here (http://oeis.org/A004169)), although reasonably good methods of approximation are known. When all else fails, use a protractor.

[Thomas Canfield]

You can also use a flexible tape measure and strap the circumference, and then divide the measured distance into the segments you desire. A line between points on opposite sides will go through the center for equal number segments. For odd number segments you have to do something more complicated.

[Dan Hintz]

Dan, that would be true IF the distances measured follow the circumference - they don't - you are measuring off chords. You get 6 equilateral triangles.

BTW the previous method will allow you to subdivide the 6 slices into 12, 24, etc...

Dangit, you're right... my bad. Evidently I've been out of geometry class entirely too long. Loved the idea of it all, just hated the proofs!

[Steve Doerr]

James, I just saw some place the method using the framing square and used it the other day and it worked very well. Here is my attempt to explain the method. Take the framing square and place it so the outer corner of the sq is touching the outside edge of the circle. Mark on the circle where each leg touches the outside of the circle. Draw a straight line between the two marks. This is the diameter of the circle. Rotate the square and repeat the same procedure. Repeat as necessary. Where the lines cross this will be the center of the circle. This works nicely since most circles we cut are not truly round and this will give you a nice approximation to the where the center of the circle is located.
HTH
Steve

[robert baccus]

A compass adjusted to approximately the radius of the circle--then stuck in 3 (or more) different Places on the circumference and turn 3 arcs. It will give you the center (or a small triangle)--you can eyeball it then. Most trysquares have a center finder down on the end.

[John Brown]

James,
Go to, wood gears.ca and at the bottom left corner click on Gear Template Generator and fill out the blanks for different amount of spaces, for what you are looking for click on dividing plate mode and you will have it. This is a very interesting site.
Jack