How do I figure board width on a segmented bowl ring?

Math. Number of segments and external diameter used to calculate cord length, which is the length of the segment

There must be a way to calculate it, but I find it easier to just measure it off a drawing. There is a picture of my doing this on my bowl page near the bottom at:

I do some bowls using a scroll saw to cut the rings. This is more economical on the wood. Ray

The extra width you need depends on a lot of factors, including how many segments you have in each ring. There's a bunch of trig involved.

Try this:

That page will do the math for you.

Thank you. But it's not the length I need, that is relatively easy. It is the width, as in the difference between the short length and the long length. So I know how wide a strip of board I need to cut.

Jim

Right, I have segments.exe that does a similar thing. What I need to figure though is the width I need in order to overlay the ring below enough that there won't be a gap.

Say for instance I want to build a bowl that has a 10" top diameter and is

3" high from the table it sits on. I want a graceful curve in to the botto m. How do I figure out how wide a board to use in each ring so that when a ssembled and placed over the ring below I know the overlap will be enough t o allow me to turn it say 1/8" think without poking a hole in it? Maybe I' m just over thinking it and should go with boards that would definitely not have this problem and have a little more waste.

-Jim

Jim,

I've never done this, but I would probably use somewhere around twice the wall thickness that you want to end up with. Maybe a bit more in case of the wood grabbing the gouge,and making a mess. Remember, gouge presentation to the wood never causes those yucky catches, It is always the woods fault. :-) Mean old nasty wood!

though is the width I need in order to overlay the ring below enough that there won't be a gap.

high from the table it sits on. I want a graceful curve in to the bottom. How do I figure out how wide a board to use in each ring so that when assembled and placed over the ring below I know the overlap will be enough to allow me to turn it say 1/8" think without poking a hole in it? Maybe I'm just over thinking it and should go with boards that would definitely not have this problem and have a little more waste.

Graph paper or Woodturner Pro:

- works a treat. Free for the first 30 days or something like that. Give it a try, and if you want to keep doing segmented stuff it's worth the price of admission. I downloaded it last year. Still need to pay/register, but it's not the todo list... ...Kevin

though is the width I need in order to overlay the ring below enough that there won't be a gap.

high from the table it sits on. I want a graceful curve in to the bottom. How do I figure out how wide a board to use in each ring so that when assembled and placed over the ring below I know the overlap will be enough to allow me to turn it say 1/8" think without poking a hole in it? Maybe I'm just over thinking it and should go with boards that would definitely not have this problem and have a little more waste.

There's is also Kevin Neeley's software for just under $20 at:

On Wed, 9 Nov 2011 15:47:22 -0600, jtpryan wrote (in message ):

well, I just went right to the ol' reptile brain, and made a couple of drawings. One, from the top view gave me an idea just how much width I'd need in a board in order to give me the wall thickness I thought I'd make, for the number of segments I felt I could do. The other drawing was a side elevation of sorts, showing the thickness of the board - or layer, if you will. In laying out a likely curve for the shape or profile of the project, I could see that layers with the greatest diameter change would also need the greatest segment strip width.

So, wall thickness and rate of change of diameter will both figure into how wide your segment strips will need to be for any given layer. If you use math to calculate this information, you will need matematical precision in your tool handling and wood removal, too. Personally, I go for the reptile brain approach. I may use a bit more wood, but I also get a bit more wiggle room in my design. The variability in any given sample of wood kinda demands some wiggle room. In my opinion.

Respectfully, tom koehler

Fred Holder

though is the width I need in order to overlay the ring below enough that there won't be a gap.

3" high from the table it sits on. I want a graceful curve in to the bottom. How do I figure out how wide a board to use in each ring so that when assembled and placed over the ring below I know the overlap will be enough to allow me to turn it say 1/8" think without poking a hole in it? Maybe I'm just over thinking it and should go with boards that would definitely not have this problem and have a little more waste.

That part of the "design" part. It really depends on what you are planning to do. Which means either graph paper (side-cut view) or software

746265730 You will note the fill (pink with color spots), where I made a design error and had to fill with colored epoxy