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lubbing5cherubs
17th February 2008, 10:54 PM
Hi Everybody,
I just keep coming back to the segmented bowls because it something that I want to do, but this is bothering the heck out of me. I bought myself the book "Woodturning with Ray Allen" I would love to have a go at making some of his bowls but it brings me to a problem. How do you work out how much wood taht you would buy to make the bowl? Maths and me do not agree at all. So I am really embarrased asking for help. :- How can I work out how much the wood do you need to make a segmented bowl. I know I have all the tables but that bit difficult to take to a shop to buy wood. Then they talk into inches and that throws me again.
Any help be much appreciated.
bye
Toni

Ad de Crom
18th February 2008, 12:29 AM
Hi Toni, well start with making a plan, by making a drawing, using autocad, or if you don't have such a computer programm, you can do it also by making a sketch by hand om paper, just like my American penfriend buddy does.
You have to make the decision, how much segmented rings you are using for such a bowl, and how much segments in a segmented ring, for example
12 segments, than you have 30 degrees segments, so if you have a mitre saw, than the cutting angle is 15 degrees, the most simpliest way to start. Make always half segmented rings, flatten these rings, and glue them together. If you work precisely, than you will notice that you don't have to do much flatten work on the half segmented rings, or not at all.
Flatten the half segmented rings can be done with the help of a disc sander or a beltsander, or if you don't have such device, by hand with the help of hand planer, this last option need some skills.
Glueing the segments can be done on a flat surface.
Also what you need is patient.
Hope this will help you out.

Ad

joe greiner
18th February 2008, 01:58 AM
Maths and CAD can make the work go cleaner, but you can dip your toe in it without them. Firstly, make your first go at it somewhat simple - maybe only 4 or 5 rings/layers, and 12 segments per layer to utilise detents or highlighted marks on your mitre saw, as Ad suggests. Draw a full-size plan view of each layer on paper with the segment joins identified. Cut out the paper parts, and rearrange to put them "back" on the timber stock, separated to allow for cutting kerfs. Measure the amount of timber needed - units of measure don't matter until this stage. Assemble the rings offset by one segment (like Running Bond in brickwork) to exploit the more robust strength of side grain to side grain gluing. The mitres don't have to be perfect, except you might need to do some end sanding on the last segment of each ring to get a good fit - might even make a more interesting pattern.

Joe

Richard Findley
18th February 2008, 05:53 AM
Hi Toni,

I don't do segmented work myself, I haven't the patience:~! but I know several guys that do and they all say that the best thing about this kind of work is the fact that you can use off cuts to make quite stunning pieces:2tsup:!

I guess this is the case until you try some of the advanced stuff with intricate designs and motifs in the segmenting. For your first attempt however you should be able to use off cuts and stuff that other woodworkers would throw away. That way your first attempt, which I would guess you would try a sort of alternating dark/light sort of design you simply need a few lengths of pale and dark timber. Planning can be quite minimal for this first one. From this you should get a feel for how it all goes together and the cuts and designs possible.

Good luck Toni. I look forward to seeing your segmented masterpieces:2tsup:

Richard

Taffsmania
18th February 2008, 07:08 AM
Hi Toni.
As Richard said scraps to start with or you can try this little program (Segmented Project Planner) it is very good and lets you know how much wood you need for each layer.
Keith

Taffsmania
18th February 2008, 07:39 AM
Hi Toni.
You can read all about it here and also download a 30 day trial.
http://www.segmentedturning.com/software.htm

Keith

Skew ChiDAMN!!
19th February 2008, 05:14 PM
Or for your first attempt or two, you could just find an ordinary bowl with a nice shape and try to copy that - only segmented, of course. :)

Then you could measure around the bowl with a dressmakers tape every inch - or cm or whatever thickness you want the bands - to get a pretty good idea of how much wood you'd need. I'd still add an extra 10-25% or so, just to allow for knots & cracks in the wood, or... well... the inevitable "cock-ups." :;

Sort of a hands-on approach instead of sitting down and planning it out on paper first.