WOODTURNERS OF SOUTHWEST FLORIDA
HOW to TURN a BOWL from a PLANK
SEGMENTED BOWLS - May Demonstration given by John and Bob Gerald
SETTING UP OF THE LUMBER:
1. Measure the width of the lumber (board).
2. Double the width and cut the length to this dimension
plus ½ inch or so.
3. Plane the edges square to butt together.
4. Plane the top and bottom face of the lumber to have
a level glue surface (this could have been the first step).
5. Butt the two pieces of lumber and clamp at the ends
so as to be able to mark the circles.
6. Mark the outer circle. This is the maximum limit of
the circle/bowl.
7. Take a piece of cut board or measure the thickness
of the lumber and lay out the circles.
8. Note the last (smallest circle) will be to the bottom
of the bowl less two (2) times the thickness of the lumber.
9. You can now number the circles and sides (A-1, B-1,
etc.) since they will not show when pieces are glued.
10. Cut the circles on the band saw with the table tilted
at 45 degrees angle towards you. Cut all of the circles out (both
sides). Note: a. Cutting cross grain and end grain changes the direction
the saw will want to cut; b. Start and end cuts at 90 degrees to the edges
of the board; c. Sand sides of the board at each cut to keep the wood curled
at the bottom from dragging on the table (or hanging up).
11. Sand all of the wood pieces to eliminate any curled
edges omitted above.
12. Glue the ends of each circle together to make a complete
circle for each layer.
13. It is now time to look at the grain of the wood or
any special featuer to create your bowl design. Note: a. Grain in line;
b. Grain at 90 degrees to each layer and c. Combinations of the above.
14. The grain in one direction for all levels is least
stable. Every other layer at 90 degrees is the most stable. Stable
meaning that the bowl will keep its shape at different speeds and when
cutting the inside and outside.
15. Glue the circle layers together. Usually this
is done upside down with something to hold the layers down or close together.
16. Glue on the glue block that is the size of the chuck
you are using.
TURNING
1. If you turn the outer surface to the finished dimension
and then turn the inside, you will find that the outside may have changed
shape.
2. If you run the lathe at too high a speed the bowl
will change shape.
3. You should cut the outer surface from the headstock
to the tailstock, except at the edge where the opposite direction is required
to keep from splitting the edge.
4. Do not back cut against the grain too long as it will
catch and cause you to tear the bowl.
5. For the inside surface turn from the bottom to the
outer rim of the bowl.
6. The thickness of the bowls should be between 1/8 to
¼ of an inch.
7. Sand the surface and finish.
8. Cut off the bowl from the glue block and finish the
bottom.
THE END.
John H. Gerald
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