"Catherine Jo Morgan" wrote in message
...
I do have a height gauge that works pretty well if I want to mark an even
rim around the top of a bowl form. What I'd like to do now tho is slice a
bowl form. Picture a bowl upside down. I want to mark a line on the curved
surface that will cut it in half -
Alrighty then, In my mind I see that we started this exercise with cutting a
sphere in 1/2 to get the bowl, now you want to cut the bowl in 1/2 again to
get a 1/4 sphere. Instead of turning the bowl upside down, turn it so that
it is flat up against a verticle surface (wall?) then use your height guage
(on the floor) again to mark across the middle and you have two 1/4 spheres.
or perhaps make a slice so that one part
is less than half, the other more than half.
Ok here you have to not have the bowl verticle, but at some angle that gives
the resultant peices you want. If you want to make your bowl into a 1/3 and
2/3 sections then tilt the bowl up at 60 degrees ( 180degrees/3) and make
your mark. The height of the marker will be set at a point on the rim of the
bowl that intersects a line drawn on the bowl that is across the diameter
and parallel to the floor. This assumes that you want a pie shaped cut, as
you would cut a mellon for breakfast.
If you want to cut at a right angle to the rim of the bowl then leave the
bowl verticle and set the height guage at whatever proportion of the height
you want to section the bowl at.
I need the cut to be as
straight as possible so I can then attach the bowl section to a flat base.
(I'm working on wall hung pieces.) Maybe if the laser level were pointing
down from above, it would give me a line across the whole surface and not
just half at a time?
"larry g" wrote in message
...
I would think that a good old fashioned height gauge would be the proper
tool to use. A laser would only illuminate 1/2 the hemisphere and you
would
have to reposition the light or the item being marked. Do you have any
metalworking books that show the use of a height gauge used for laying
out?
Pretty simple instrument for what it does. From looking at the art
work
that you are doing I would think that you could fab up something that
would
do what you need to do. You only have to hold the marker at a fixed
height
while you move it around the piece being marked out, while the piece
being
marked is held steady and the sliding marker is on a flat surface that
is
parallel to the to the line you wish to draw. For precision metal work
this is done on a surface plate. You could probably get away with a
piece
of glass or a good flat counter top. I could send you pictures if you
like.
lg
no neat sig line
"Catherine Jo Morgan" wrote in message
...
I think a small laser level would help me a lot, but I'm not sure.
Let's
say
that I have a curved surface, a rough hemisphere for example. I'd like
to
cut the hemisphere in half, or at least slice it so the cut edge is
straight
and can be fitted onto a flat surface. Could a laser level lay a
straight
line onto the curved surface, so I could mark it for cutting?
Perhaps there's a better way to do such marking? I know a laser level
will
give me a pretty broad line at close range. Is there a way to
distinguish
among the different models to find the one that will have the thinnest
line
at close range? Are the lines or dots always smaller the closer you
are?
Also - would it be kind to my eyes to wear shaded glasses when using a
laser
level? I do know not to point the laser AT my eyes (or at anyone
else.)
But
the line itself is pretty bright, right? So maybe shade 3 if I can
find
some
clip-ons? TIA
--
Catherine Jo Morgan
http://www.cjmorgan.com
online artist journal: http://radio.weblogs.com/0120691/