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Pattern table

H

heteneik

New member
Hi everyone!

Have anyone ever met with the problem that when you create pattern table sometimes the features are starting with counter-clockwise direction and at the half way it is turned back the clockwise direction.. and didn't get a full pattern only a half?

If anyone knows that problem, what can be the solution?

Thanks in advance

Regards
Erik
 
Are you trying to pattern a feature radially / in a circle? Maybe just make sure that the dimension which drives your pattern is correct.

Could you post a picture of your feature and the pattern table?
 
Why not just pattern the feature around an Axis?

I'm not really sure why the table pattern is not working...
 
The reason is that is a programmed model, and engineers are creating models from a layout drawing..this pattern is driven by relations and from a table on the drawing. Sometimes this pattern will not be symmetric.
 
It could be the '6' dimensioned to a fixed datum that's causing a problem, but it seems unlikely.

As a workaround to the problem you could do this: Copy the feature -> Paste Special -> Apply Move/Rotate Transformations. Rotate the feature around an axis, but leave the value at 0.00.
You can now pattern the copied feature using a pattern table, and use the 0.00 as your driving dimension.


Edited by: neuronex
 
Oh my holy god.. my whole model was built with the method but only with surfaces.. i don't know why i didn't try it with a simple curve :)

Thanks neuronex.. sometimes it is solve the problems when another people is seeing the tree through the forest:)
 
smiley20.gif
 
This is a frequent problem I have encountered. Copy and
pasting with rotation is ok for a few instances. This
problem occurs due to references selected. At times it
really beats me.
This used to be a problem in WF (for regular pattern)
before the axis pattern was introduced. We had to pattern
the plane and construct a reference pattern of the
feature. PTC's answer was that is the intended behaviour
occurring due to positive and negative side of a plane!!!
At-least with axis pattern that is now resolved.
I would check the references selected for the sketch. DO
NOT select any of the Datum planes for sketch reference.
Frankly, this looks like a bug in the software. Pattern
instances beyond 90 deg or beyond 180 deg, seem to get
mirrored. Maybe I should report this to PTC.
smiley11.gif

Edited by: SRINIVASANIYER1
 
After fiddling around a bit, I think I have a solution...
Let us say the pattern angles are 20, 45 and so on.
1. Draw two circles. Create points pnt0 and Pnt1 (Pnt1 is
used to orient the slot) on the curve {select the
complete curve) such that Pnt0 is at 20 deg to the
horizontal. To ensure it input the ratio as (20/360).
2. Create the slot by referencing ONLY THE POINTS.
3. Create a Group of the points and the slot.
4. Create a table pattern by varying the point dimension
(in this case it is 20/360)

27_040858_mcad.JPG">
 
This problem is most likely caused by the dimensioned centerline. Once angles for centerlines get larger than 180
 
This problem occurs due to the +ve and -ve side of a plane. Let us say the initial angle starts at the -ve side of the plane. As the angle increases and hits the 180 deg, the software takes it once again from the -ve side of the plane. Thus it vascilates on the same side of the plane. Hence, Patterning with referene to a plane may not be a correct practice especially for axial pattern.
Care should also be taken that one does not reference any datum plane while using this kind of pattern.
 
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