Advanced Part Design Exercise: Vent

jamescbonney

I am having a problem with step 16 in this exercise. I have followed the instructions for the step, but the result of the feature pattern in my part studio differs from that shown in the example, so I must be missing something.

There is a hint in the sketch step to dimension from the vertical and horizontal construction lines to the radius of the slot rather than the end point of the arc. I have tried changing the vertex selected for the dimension and it did change my result, but I did not get the result shown above. 

Below are screenshots of the sketch, first circular pattern, and the troublesome second circular pattern. 

Here is a link to the document: https://cad.onshape.com/documents/c6d77c61f4665964b85bd18f/w/4c54d3eb1fb2eab39d5f4b28/e/c89354e2446653e5ef20b831

Here is a link to the exercise: https://learn.onshape.com/learn/course/advanced-part-design/advanced-features/exercise-vent?page=2 

tim_hess427

Maybe the highlighted dimension is supposed to be perpendicular to the construction line, but in the messed up model its setting a vertical distance between the center of the arc and the endpoint of the line. 

Try erasing that dimension and re-doing it, but make sure you select the construction line instead of the end-point on the line?

EvanReese

@tim_hess427 was right. the dimension needed to be between the arc center and the line, not the endpoint of the line.
 
It feels confusing because the result is the same in this sketch, but the results in the patterned sketches are different. When it's dimensioned to the point, the patterned sketches start to do this because the dimension is still vertical.

bruce_williams

@jamescbonney

I was confused on that for a bit also. It is not relevant if you choose arc center or vertex of the slot centerline.  What the others are talking about is the horizontal construction LINE, and not choosing its vertex.

EvanReese

I just worked through the exercise, and it worked for me, but I fiddled around with it trying to reproduce your results and couldn't see how. Can you make your document public, not just share a view-only link? Otherwise we can't dig into your features to see how it's set up. In looking at yours though, It could be something with this dimension. It seems to get bigger with each iteration of the sketch in your screenshot, but it should always be 5mm.

tim_hess427

Maybe the highlighted dimension is supposed to be perpendicular to the construction line, but in the messed up model its setting a vertical distance between the center of the arc and the endpoint of the line. 

Try erasing that dimension and re-doing it, but make sure you select the construction line instead of the end-point on the line?

KatieHuffman

@jamescbonney follow what @tim_hess427 points out. In step 12, when you add the dimensions you have to be careful how you attach the leaders to the sketch geometry as it says in the hint. This is important to get the pattern to update correctly later in the design because depending on how you attach the leaders changes how the variables pattern.

jamescbonney

Thanks for the responses. @Evan_Reese @tim_hess427 @KatieHuffman

I have made the document public. 

I will check back to this exercise and see if the suggested solutions resolve the problem. 

EvanReese

@tim_hess427 was right. the dimension needed to be between the arc center and the line, not the endpoint of the line.
 
It feels confusing because the result is the same in this sketch, but the results in the patterned sketches are different. When it's dimensioned to the point, the patterned sketches start to do this because the dimension is still vertical.

jamescbonney

Thanks @Evan_Reese

To select the arc center did you hover over the end point of the arc and then move to the center? 
I right clicked and used the select other option and tried the available options, but apparently I did not have luck selecting arc center. 

EvanReese

I didn't do anything special there. I just clicked the point then the edge. I highlighted the two things to dimension to.

bruce_williams

@jamescbonney

I was confused on that for a bit also. It is not relevant if you choose arc center or vertex of the slot centerline.  What the others are talking about is the horizontal construction LINE, and not choosing its vertex.

jamescbonney

@Evan_Reese @bruce_williams

Ah! I see now! I misread the clue. 

Ashdancan

Hello

I did all procedures but in the second circular pattern, nothing happened.

Ashdancan

Hello

I did all procedures but in the second circular pattern, The result was absolutely different. I did all requirements mentioned in the exercise but failed.

Ashdancan

Hello

I did all procedures but the result was absolutely different. I did all requirements mentioned in the exercise but failed.

 please anyone can help me??. I think I did all correctly.

Thanks for all

Ashdancan

Ashdancan said:

Hello

I did all procedures but in the second circular pattern, nothing happened.

Ashdancan said:

Hello

I did all procedures but in the second circular pattern, The result was absolutely different. I did all requirements mentioned in the exercise but failed.

S1mon

@Ashdancan
It would be much easier to help you if you can share a public document. These kind of patterns are tricky and little details make a big difference.