Re: Simple way of making Golf Ball with Solidworks!

On 6 Mar 2006 15:26:08 -0800, ed1701@xxxxxxxx wrote:


TOP wrote:
If you look at the link it seems to be what they did on some golf
balls. You cannot project a sketch, but you can get points from a
sketch to project onto a surface. Very tedious, but doable.

yes, tedious, but fascinating. Modeling the ball is dull - just
patterning/mirroring a bunch of revolved cuts (yawn, and yes Cliff, I
tried it).

But I don't think you got good results <G>.

But trying to project an icosehedron on a sphere was quite educational.

No need for projection, which would introduce trig errors.
Just get them the same "diameter" to begin with such that either
the vertexes or the face centerpoints lie on the sphere.
Then do the same with other icosehedrons rotated in 3D
about the center of the sphere.

One thing that caught me up in a big way was that, though you can
split a 2D triangle up into four identical 2D triangles, it doesn't
work that way on an equalaterial triangle on the face of the sphere
(which I didn't catch until wasting a fair amount of time)!

Solid trig?
Not even in planar geometry IIRC.

The
phenomenon even shows up on the wikepedia (or whatever the reference
was that you posted) picture - if you look closely, the small triangles
(with the smaller dimples) aren't equalateral, and the spacing between
the dimples requires a little adjustment.

Random guesses.

There were some other fun geoemtry tricks and gimmicks to pull this one
out, but its really about the icosehedron.

Tried other Platonic solids too?

So, thanks for the reference info, Paul. Not a bad way to burn time on
a plane.
Ed
--
Cliff
.

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