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Re: Aesthetic Face Blend- align edge?

Phenom
Phenom

@Maurizio,

I believe that is exactly what I stated there, is it not? I plainly stated it wasn't good practice when modeling above G1, which implies Class A.

Please keep that in mind that I may not be passing along info that applies only to Class A....not everyone is doing the same things with surfaces that you may be.

-Tim

Re: Aesthetic Face Blend- align edge?

Phenom
Phenom

@TimF wrote:

I believe that is exactly what I stated there, is it not? I plainly stated it wasn't good practice when modeling above G1, which implies Class A.

Please keep that in mind that I may not be passing along info that applies only to Class A....not everyone is doing the same things with surfaces that you may be.

I didn't mean to blame you for spreading bad practices (everyone can see that you spread good practices), I mentioned your point just to raise a general question about it, that is if "Could anyone post an example where modeling a half is better", which I cannot imagine either, for any kind of surface.   

Re: Aesthetic Face Blend- align edge?

Phenom
Phenom
@Maurizio,

I am confident that you and I understand most general good and bad practices when it comes to what should be done to achieve quality surfaces, meaning Class A. However, this is where things, in my opinion, can become topics for debate because there are no concrete (written) standards to follow for Class A - it's pretty much the end customer's practices that are the standards or rules. Process limitations can even lend to bending the practices we need to follow.

It's time for some sort of standard to happen, IMO. I am sure that won't be a cure-all but it will give new people a place to start as well as something to reference for when they are getting started or there is a question as to what is preferred.

Also, I feel there is too much variance as to what is considered Class A (in a global sense) - the definitions change depending upon product, process limitations and most of all, customer requirement (or should I say allowance)? I've seen automotive stylists who are trained just as you are use Mirroring for Class A - I'm not saying it's right or wrong - I'm just saying it's being done, whether WE agree with it or not, whether we actually follow it or not. I've seen tutorials from different sources that flat out state below G2 is not Class A then some state it must be G3 minimum. I've also seen continuity taken out of the equation and Class A be defined as a lightweight, simple, organic surface, no higher than 7 degrees. Which is "good practice" and which is "bad practice"?

I hope you see the point I'm trying to make - whether mirroring is good or bad practice, I'm going to discuss BOTH because it's a command that is available in NX and just about every "name brand" CAD software out there. The technique is being used (whether it's good practice for you or me or anyone else) and since I've used it for non-Class A situations I can confidently state it is a time saver, just like Patterns or Arrays or Extracted bodies (solids, surfaces).

That's all I was attempting to do - just show both sides of the coin - then let the end user or their employer/product requirements decide which practice they wish to follow.
-Tim

Re: Aesthetic Face Blend- align edge?

Siemens Genius Siemens Genius
Siemens Genius

Coming late to this thread (1st post!)

AFB has a Cross Section Orientation = Spine Curve Option.

Not using this option - typically results in: (= the original problem)

AFB1.JPG

Using the Spine Curve option:

AFB2.JPG

A good starting point for the Spine Curve is one that has the required continuity across the C/L in my case Y=0

 

Taking this one-step further:

Provided

  1. the base surfaces have the required continuity at Y=0
  2. and the AFB "Rails" have the Tangent Line definition:
    • Law Type = Cubic
    • or Law Type = Multi-transitional>Transition>Minimum/Maximum at the C/L 
      • then there is good continuity of the AFB surface & Rails across the C/L

AFB3.JPG

For the case in point there shouldnt be any need to model-past and trim to the C/L

 

 

Re: Aesthetic Face Blend- align edge?

Genius
Genius

Hi @neil_shand   What does C/L mean? Center line? Thanks!

Re: Aesthetic Face Blend- align edge?

Siemens Genius Siemens Genius
Siemens Genius

yes: C/L = Centerline

CL.JPG

Re: Aesthetic Face Blend- align edge?

Genius
Genius

Hi @neil_shand   Then I can understand what you taught in your previous post. Very helpful for the use of AFB. Thank you!

 

It seems that "Law Type = Cubic" is key for the success. This principle should be valid for many other commands.

Re: Aesthetic Face Blend- align edge?

Genius
Genius

Re: Aesthetic Face Blend- align edge?

Siemens Genius Siemens Genius
Siemens Genius

Its a question like:

What tool to pull out the toolbox to do a job...  Hammer or a screwdriver...

Everyone has their preferences and opinions.. I'll add mine for folks to agree / disagree with....

 

My View for Styled Blend:

I'd look to use this for:   Smoothly blending between 2 Primary Surfaces. To create a result that is ~ a sheet with 3 Primary Faces.

My definition of these primary faces:    Large and fundamental to the product shape:

Best results is between single face - to - single face type.

Basically produces a result where the user has some control over each of the tangent lines as surfactant states.

 

Automotive example of a primary  ~To connect the glass windshield to the Roof...  (Note: There are a few different ways to handle this problem type.. to do this properly you have to think about a zero-knot (single patch) result...) and maybe styled blend isnt sufficiently real  A-Class.....

 

My View for Aesthetic Face Blend:

To Create secondary surfaces against 2 primary sheets.

My definition of these secondary faces: To smoothly add high quality blends, usually much smaller than the primary sheets.

Can run across many faces in each of the sheets.

The base sheets need to have good (sufficient) continuity to start with. There is no point trying for a G3 AFB when the base sheets are each only G1...

The tangent lines tend to be defined by Rolling-Ball (contact),  Disc (Contact (Spine option))  type or Cord width type.

 

Automotive exterior example:  Much of the exterior of vehicle blending (visual styling "creases") where Blend size < ~10mm - and good reflective quality is required.

 

Automotive interior example:   Much of the hard and soft plastic blending where blend size < ~20mm - where no visual evidence of where the blend tangent is apparent.

 

as we all know: other folks will have other views.

My examples are only my personal rule-of-thumb. and with all rules - its good to break them occasionally...

- Neil

 

 

 

 

 

 

Re: Aesthetic Face Blend- align edge?

Genius
Genius

Hi @neil_shand   Thank you for your invaluable summary of both important blending commands!