Help creating an gradient that transitions at an angle.

[dominick4EV2S]

I need help making a transition for this region of my part:

It currently has a step transition but i want it to be more of a gradient transition like this:

 

These images are from a practice model that I have been playing with before I implement this feature on the main model. 

The dilemma is that I want keep the angle that is on the right of the feature in the first image, but have it transition as more of a gradient rather than a step. Kind of a  mixture of the two. The feature on the first  image was created using the extrusions (cut) tool at an angle.

The second image was created using a surface modeling method. I've  attached a .f3d file of the practice model  to this post. The main model, from the first image, can be transitioned from a solid model back into a surface model, so I am not worried about that. I need help figuring out a workflow/method utilizing surface modeling to achieving this. I hope this make sense, feel free to ask if you need clarification on what i am looking for,

 

[davebYYPCU]

I ave reviewed the file, but don't understand what you want to do.

I can see the recessed face, with Sweep, and Loft.

I have not found the sketch shape in the extrude cut pic.

Might help...

[jeff_strater]

same here.  I'd need some more guidance on what you want the result to look like.  I think the answer, whether you do this via surface operations or solid operations, is a Loft of some kind.  Here is one I did using solid Loft, but there are lots of options here

[dominick4EV2S]

After some playing  around and adjusting the work-flow, I was able to get the results I wanted. It was a matter of playing around with boundary conditions  in the loft and patch commands while in the surface workspace.  Here is what i was looking for:

The first image below has a gradient transition that starts at an angle and end at an angle. The second  image below has the gradient that starts vertically and terminates at an angle. 

[dominick4EV2S]

@jeff_strater thanks for the  advice, If you read my reply  to this thread, I utilized lofts and patch while in the surface workspace. This gave me the results I wanted, but in my main project, converting my model results in over 100 surface body to be created and then restitched. If you can get the same results utilizing solid modeling it would simplify my timeline and work better with the other features I created. How did you create that feature utilizing solid loft, and can you recreate what I did but utilizing solid loft commands in the solid workspace. If you can demonstrate it, that would very much be appreciated!

[TheCADWhisperer]

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@dominick4EV2S wrote:

 I was able to get the results I wanted.

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@dominick4EV2S 

Can you Attach this file here?

[dominick4EV2S]

Here is the test model  were I got the results I wanted. Still figuring out a way to get the same results utilizing the solid loft tho.

[TheCADWhisperer]

@dominick4EV2S 

I think we can get this done without having 100 surfaces (in the actual part).

But we want robust and predictable technique that will transfer from test model to actual model.

[jeff_strater · Accepted solution]

I'll share what I did in that model.  Some of it will be applicable to your model, some will not.  The short answer is:  rail curves.  This gets you the most control over the transitions.  Here is the thought process I went through.

1.  created a block, centered on the origin:
   
2. created an offset workplane from the top face, and two rectangular sketches:, defining the top and bottom of the region to cut:
   
3. then, added a 3D sketch and started to define spline curves by using "Include 3D Geometry" to get the points from the two sketches into the 3D sketch, and 3D Splines for the curves.  You can use Move to tweak the handles (I can demonstrate if you are not familiar with this).  It was at this point that I realized I should have just modeled 1/4 of it, since in this test model, everything is  symmetric.  This let me create 1/4 as many rail curves.  I created this 3D sketch.  The selected curves are all that are in the 3D sketch:
   
   here they are in isolation:
   
   
   
4. then, I just created the 1/4 loft:
   
5. and, finally, two Mirror Features (Optimized) to create the rest of the cutout:
   

You won't be able to use Mirror, since your desired shape is not symmetric, which probably means you will need more rail curves.  But, once it is all set up, then just editing those rails using 3D Move allows you to tweak the shape nicely.

Model is attached

[TheCADWhisperer]

@dominick4EV2S 

As I go through this, I have to wonder if the Design Intent is for these angled lines to be parallel?

[dominick4EV2S]

Thanks for mentioning that my sketches were not defined.  I  just threw  this  model together to proof my work-flow/ methods . Typically I do define my sketches, but this was just slapped together as a test piece. 

[dominick4EV2S]

I'm still deciding how I want to go about the gradient transition. But for the model that I shared, yes those two lines are parallel. This is another feature i put together utilizing the surface workspace. In the photo below, the right side has two parallel lines while the left side has a vertical line that transitions to angled line.

 

[dominick4EV2S]

Thanks for the instruction, this is very helpful. Having more  control over the transition will definitely help with shaping this feature. I think i might have an idea how i can use this work-flow to achieve the geometry that I looking for. Do you think it is possible to  do this with the sketch having fillet edges with solid loft.  Something like this:

or  this:

Again, these were created in the surface workspace and the sketches are not defined. 

I've attached the project to this reply.

Thanks!

  

[TheCADWhisperer · Accepted solution]

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@dominick4EV2S wrote:

Typically I do define my sketches, but this was just slapped together as a test piece. 

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@dominick4EV2S 

I wanted to make sure of that since your numbers were so close to logical values.

I see some users eyeball to the grid without using dimensions.

See Attached file for alternative technique.

In addition, you could also add Rails as suggested.

[dominick4EV2S]

@TheCADWhispererThank you for this helpful video. You help me better understand how to transition my  model from a solid to surface and back. That is a better method than unstitching the entire model before creating the feature. I'll post back here once I successfully incorporate the feature into my main model.

[dominick4EV2S]

If anybody has any other method, feel free to post. This is one of these situations where there are multiple different ways to get to the same results. 

Thanks guys for the help!

[johnsonshiue]

Hi! If I understand the design intent correctly, it might be easier by using Draft command in Solid Model -> Modify tab.  You will need to make it a solid body first. After the side faces are drafted desirably, use Fillet command to smoothen the sharp edges.

Many thanks!