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moyo October 24th 03 03:00 AM

segments, how to figure?
 
I'm not real swift with mathematics and naturally suck at Algebra so,
how does a person using his fingers (toes optional) figure the outside
and inside widths of the various segments? I'm turning a walnut bowl
with an outside diameter of 7 and 3/4.

Thanks for the advice

Moyo

DJ Delorie October 24th 03 03:21 AM

segments, how to figure?
 

moyo writes:
I'm not real swift with mathematics and naturally suck at Algebra so,
how does a person using his fingers (toes optional) figure the outside
and inside widths of the various segments?


By letting someone else do it ;-)

http://www.delorie.com/wood/segturn.html

Nova October 24th 03 03:26 AM

segments, how to figure?
 
moyo wrote:

I'm not real swift with mathematics and naturally suck at Algebra so,
how does a person using his fingers (toes optional) figure the outside
and inside widths of the various segments? I'm turning a walnut bowl
with an outside diameter of 7 and 3/4.

Thanks for the advice

Moyo


The easiest way is to use software written for the job.

See Kevin Neelley's "Turned Wood" web site for one example:

http://www.turnedwood.com/software.html

--
Jack Novak
Buffalo, NY - USA
(Remove "SPAM" from email address to reply)



Bill Rubenstein October 24th 03 03:45 AM

segments, how to figure?
 
In article , says...

moyo writes:
I'm not real swift with mathematics and naturally suck at Algebra so,
how does a person using his fingers (toes optional) figure the outside
and inside widths of the various segments?


By letting someone else do it ;-)

http://www.delorie.com/wood/segturn.html

Another way -- used by a well recognized segmented turner who just
happens to be an engineer --

He draws the thing full size and then measures off the drawing. He is
good with math but thinks the drawing has lots of advantages.

Bill

Bob Pritchard October 24th 03 04:29 AM

segments, how to figure?
 
Draw a 7-3/4" circle on a piece of paper. Decide how many segments you want to
use.
Lets say you want 8 segments.
Divide the circle into 8 equal parts and measure off of your drawing.
If you want to use more segments just divide the circle into more equal parts.
Or try the woodturner pro software. With the software you don't even have to
know how to add. :-)
http://www.woodturnerpro.com

I'm not real swift with mathematics and naturally suck at Algebra so,
how does a person using his fingers (toes optional) figure the outside
and inside widths of the various segments? I'm turning a walnut bowl
with an outside diameter of 7 and 3/4.



Bob, Naugatuck Ct.
http://www.outofcontrol-woodturning.com

Steve Marshall October 24th 03 10:19 AM

segments, how to figure?
 
Check out www.turnedwood.com where you will find lots of ggod info about
methods etc for segmented turning.

"moyo" wrote in message
...
I'm not real swift with mathematics and naturally suck at Algebra so,
how does a person using his fingers (toes optional) figure the outside
and inside widths of the various segments? I'm turning a walnut bowl
with an outside diameter of 7 and 3/4.

Thanks for the advice

Moyo




Fred Holder October 24th 03 04:38 PM

segments, how to figure?
 
Hello Moyo,

As several people have stated, the easiest way is to use one of the segmenting
software packages. I've used a couple of them with good results. However, I did
more segmenting working from a drawing. Here is how I did it:

I used a piece of 1/4" grid paper with the light blue lines and sketched the
bowl shape that I was interested in doing. You only need to draw half of the
bowl. I always used 3/4" boards to make my segmented rings, so it was easy to
start at the bottom (foot of the bowl), mark up three squares and draw a line
through the bowl shape. Continue doing this until you run out of bowl. You have
just laid out the segmented rings.

Now, take a pencil compass and put the point on the centerline and set the
pencil to touch the outside of the bowl. Draw a circle with this setting. Decide
how thich you want the bowl wall and reduce the setting of compass to touch the
inside wall point and draw another circle. You have now constructed the inside
and outside dimentions of your bowl at that point. Decide how wide the board
will be from which you'll cut the segments. I used to use 1-1/2" boards for my
segments. Eyeball a mark between the two lines. Then make marks 3/4" either side
of the center line of the wall thickness. With your compass, draw circles
through each of those 3/4" marks. Now, draw horizontal and vertical lines
through the center of the of the circles. You've now divided it into four
segments. To get to 8 segments, divide each of these 1/4th segments into half.
To get to 16 segments, divide the 1/8 segments in half. Then draw a line
perpendicular to a radius line that bisects one of the segments. Now draw
perpendicular lines to this line that touches the inner and outer circles. You
have now drawn one of your segments. Take you measurements from that to cut the
segments for that circle.

Repeat this for each ring of the bowl and you've done what the software can do
in a couple of minutes. If you're careful on your layout, everything will work
our very well.

I hope this is clear.

Fred Holder
http://www.fholder.com/

In article , moyo says...

I'm not real swift with mathematics and naturally suck at Algebra so,
how does a person using his fingers (toes optional) figure the outside
and inside widths of the various segments? I'm turning a walnut bowl
with an outside diameter of 7 and 3/4.

Thanks for the advice

Moyo



October 25th 03 04:07 PM

segments, how to figure?
 
Go to Kevin's site and print the instructions for making the project
on-line...The best I've found if you are sticking to 90 deg blade tilt
settings..If you need compound mitres then use any of the software
available...Rick
"moyo" wrote in message
...
I'm not real swift with mathematics and naturally suck at Algebra so,
how does a person using his fingers (toes optional) figure the outside
and inside widths of the various segments? I'm turning a walnut bowl
with an outside diameter of 7 and 3/4.

Thanks for the advice

Moyo




October 25th 03 04:11 PM

segments, how to figure?
 
Go to Kevin's website and print the instructions for his sample
project...This method is very easy with minimal math,,,If you need compound
angles then use any of the available software...Rick
"moyo" wrote in message
...
I'm not real swift with mathematics and naturally suck at Algebra so,
how does a person using his fingers (toes optional) figure the outside
and inside widths of the various segments? I'm turning a walnut bowl
with an outside diameter of 7 and 3/4.

Thanks for the advice

Moyo




Ddoobie October 25th 03 07:01 PM

segments, how to figure?
 
Moyo,
That was the same question I had over a year ago. The advice I got was to buy a
book on segment setup and turning. I got mine off E-BAY for less then form a
book store. I have gone back to that book several times and read it over. They
have drawings and charts already figured out, copy them and take it to the shop
where you need it.

georgetroy October 26th 03 03:58 PM

segments, how to figure?
 
(Ddoobie) wrote in message ...
Moyo,
That was the same question I had over a year ago. The advice I got was to buy a
book on segment setup and turning. I got mine off E-BAY for less then form a
book store. I have gone back to that book several times and read it over. They
have drawings and charts already figured out, copy them and take it to the shop
where you need it.


This is the formula to figure segments.
Diameter x 3.1416 = circumference. Divide by the # of segments =
length. For example. 7" x 3.1416 = 21.9912 divide by 12 = 1.832 is the
length of your segment. This is for tip to tip. You can go to my
segmented site for more instructions.
http://www.georgetroygraphics.com

Bob Pritchard October 27th 03 02:33 AM

segments, how to figure?
 
Hi George, With all due respect using Pi in segmenting introduces error. The
reason is as you know Pi is a measure of the circumference of a circle.When we
build a segmented ring we are stepping around with straight lines. The segments
have to be slightly longer to acomplish the same diameter. While a ring with a
lot of segments won't have a substantial error a ring with fewer segments will
have more of an error.
Draw a ring with a smaller amount of segments then do the math and you will
find the pi method results in a shorter segment length thus a smaller finished
diameter.
In some designs enough error to cause major problems.



Bob, Naugatuck Ct.
http://www.outofcontrol-woodturning.com

David S Lawson October 27th 03 11:06 AM

segments, how to figure?
 
In message
(Bob Pritchard) wrote:

Hi George, With all due respect using Pi in segmenting introduces error. The
reason is as you know Pi is a measure of the circumference of a circle.When we
build a segmented ring we are stepping around with straight lines. The segments
have to be slightly longer to acomplish the same diameter. While a ring with a
lot of segments won't have a substantial error a ring with fewer segments will
have more of an error.
Draw a ring with a smaller amount of segments then do the math and you will
find the pi method results in a shorter segment length thus a smaller finished
diameter.
In some designs enough error to cause major problems.


Yes, that method will produce a 7 inch ring at the segment tips and not
at the centres which is what I assume is wanted.

To expand this thread a little, does anyone know of a computer software
program to make these calculations, to run on a Risc PC instead of
windows.
Dave Lawson
Redditch UK

Ralph Heasley November 2nd 03 01:46 AM

segments, how to figure?
 
There was a fellow on the KC woodturners site who had a computer program for
sale. Can't remember his name but he did the fancy segmented bowls shown on
the site.

"georgetroy" wrote in message
om...
(Ddoobie) wrote in message

...
Moyo,
That was the same question I had over a year ago. The advice I got was

to buy a
book on segment setup and turning. I got mine off E-BAY for less then

form a
book store. I have gone back to that book several times and read it

over. They
have drawings and charts already figured out, copy them and take it to

the shop
where you need it.


This is the formula to figure segments.
Diameter x 3.1416 = circumference. Divide by the # of segments =
length. For example. 7" x 3.1416 = 21.9912 divide by 12 = 1.832 is the
length of your segment. This is for tip to tip. You can go to my
segmented site for more instructions.
http://www.georgetroygraphics.com




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