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challenge

I

Israr

Active member
To create an extrusion normal to the surface of the ball you need to create a point on the surface of the ball, then create axis through that point and normal to surface, now through a series of datum planes you can create the required extrusion. My question is how to pattern it on the surface of the ball such that the extrusions are equally distributed over the ball surface.


Israr
 
Hi Israr


These are the steps


1- Create the ball<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />


2-Create a datum plane through the centerangled which will control the position of the protrusion.


3-Create intersect datum curve using this plane and ball surface


4-Createa composite approximate curve from this curve


5-create a datum point on composite datum curve using relation (you can use any value, you are going to do relation after)


6-Create a datum axis through the the datum point and normal to ball surface


7-Create a datum plan through the datum point and axis


8-Create a datum plane offset from the previous datum plan (height of the protrusion)


9-Create a protrusion using this datum as sketch plane and the datum plan from 2 as a sketcher reference plane


10-Group features 3-9 and patterns them


11-Add 2 relations 1-d4=d94 where d4 is first datum point relation dimension and d94 pattern increment dimension
2-d94=1/p95 where p95 is number of the pattern instances.


I can send you the file (WF2.0) if you wish and leave e-mail address.
 
Done.<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />


I have just tried same thing with an ellipsoid it works just fine.


Basically itcan be usedwith any closedsurface.
 
Pedja,


well done, but what I want is still a problem. How to pattern it over the entire surface of the ball not over a circular line.


Israr
 
Just a quick question, what is wrong with creating a tngenet plane as origionally suggested and then simply creating a two sided extrusion with one side being "extrude to surface"? I'm not at my work station, but it should work.


Big Jim
 
pedja666's solution should work.



When you pattern the grouped feature, select the angle of the datum
plane defined in 2) and enter an increment and quantity to fill it
between 0 and 180. Might be imperfect because of multiple geometries at
the "Poles" of the surface.



You could also repeat the steps for creating the curve in a second
direction normal to the first, but I don't think that really gains you
anything.
 
Interesting challenge, but I'm wondering why you'd want to do that. I can think of one application. What's yours?
 
Bem thanks for your interest,


In my house there is a fountain. I want to replace it with a ball type globe out of which these extrusions I use for emanating water spray.


Israr
 
Hi Israr<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />


I sent you the new part with the pattern over the entire ball surface.


For the others that wanted to see this file,I have tried to upload it butafter a "successful"upload the file is not there. I can only ask the administrator to make it work or write an article with the explanation and images. But this does not work either.
 
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